3,421 results on '"VISUAL evoked response"'
Search Results
2. Visual and somatosensory evoked potentials abnormalities among Behçet's disease patients and their relation to disease activity, severity and antiphospholipid antibodies: a cross-sectional study.
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Nageeb, Ghada S., Eliwa, Enass A., Tharwat, Ibrahim, Mohammad, Lamiaa A., and Attia, Nada Alaa
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CROSS-sectional method ,ANTICOAGULANTS ,SOMATOSENSORY evoked potentials ,VISUAL evoked response ,AUTOANTIBODIES ,SCIENTIFIC observation ,BEHCET'S disease ,SEVERITY of illness index ,SYMPTOMS - Abstract
Background: Behçet's disease (BD) is a common disease with high morbidity and mortality. Ocular, neurological, and vascular affection in BD are a major cause of such morbidity and mortality. Evoked potential (EP) studies including visual evoked potentials (VEP) and somatosensory evoked potentials (SSEP) in addition to antiphospholipid antibodies (aPL) are valuable tools for detection of ocular, neurological and vascular affection and may be used for assessment of activity and severity in BD. We aimed to use EP studies and aPL as objective tools in BD assessment. Results: Abnormal VEP was found in 76% of BD patients and has a significant association with ocular involvement (P = 0.003), Moreover, Abnormal VEP was significantly associated with ocular activity (P = 0.002). Abnormal SSEP in both median and tibial nerves was found in 62% of patients, prolonged central conduction time of median and tibial nerves was found in 46% and 22% of patients respectively and was significantly associated with neurological involvement in BD (P < 0.05). Abnormal VEP and SSEP studies were significantly associated with BD disease severity (P < 0.05) but not activity. Vascular involvement was significantly associated with elevated lupus anticoagulant and anti-cardiolipin IgM antibodies (P < 0.05), elevated lupus anticoagulant levels were associated with optic nerve involvement and abnormal VEP. Conclusion: Abnormal VEP and SSEP studies can be considered as indicators for BD severity and hence poorer prognosis. VEP study is a valuable tool in BD and may indicate ocular involvement or ocular activity. Prolonged Central conduction time of upper limb and lower limb evaluated by N13- N20 IPL and N22-P39 IPL respectively may be used to detect nervous system involvement in BD patients. Optic nerve involvement may be suspected in BD patients with elevated lupus anticoagulant, elevated LA and aCL IgM can be used as indicators for vascular involvement in BD. [ABSTRACT FROM AUTHOR]
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- 2025
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3. The influence of paradigm interface guided by different visual types on MI-BCI performance.
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Shao, Jiang, Bai, Yuxin, Yao, Jun, Zhang, Ying, Tian, Fangyuan, and Xue, Chengqi
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ARM physiology , *SCALE analysis (Psychology) , *BRAIN-computer interfaces , *ELECTROENCEPHALOGRAPHY , *VISUAL evoked response , *EVOKED potentials (Electrophysiology) , *NEUROPLASTICITY , *DESCRIPTIVE statistics , *SIGNAL processing , *PARADIGMS (Social sciences) , *CEREBRAL cortex , *SUPPORT vector machines , *FRONTAL lobe , *COMMUNICATION , *BODY movement , *COMPARATIVE studies - Abstract
Visual paradigms of Brain-Computer Interfaces (BCI) for motor imagery (MI) tasks are the basis for communication through (electroencephalogram) EEG signals. During the MI-BCI user training process, this study analyzes and summarises four different visual paradigms and compares their impact on the outcomes of MI-BCI training. Four different visual paradigms are experimentally compared through classification outcomes and subjective evaluation. EEG features were extracted via Common Spatial Patterns (CSP) and passed to a Support Vector Machine (SVM) model for their classification. The results show that all four types of visual paradigms have a significant impact on the outcomes of MI-BCI training, with Paradigm Set II having the most significant impact. This is because paradigm set II offers a paradigm interface with relatively low visual complexity on the basis of action observation, and visual guidance with more clarity and more accurate EEG classification. [ABSTRACT FROM AUTHOR]
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- 2025
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4. Comparison of mathematical models of potential distribution on the scalp surface during visual evoked potentials generation.
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Konstantinova, Z. A., Belyaev, A. M., Dmitriev, A. N., Spitsyna, P. G., Chekhvalov, R. D., Kondaurov, L. R., Morozova, S. N., and Sergeeva, A. N.
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STATISTICAL models ,MATHEMATICS ,VISUAL evoked response ,ELECTROENCEPHALOGRAPHY ,SIMULATION methods in education ,BIOMEDICAL engineering ,SCALP ,SENSITIVITY & specificity (Statistics) ,ALGORITHMS - Abstract
The distribution of visual evoked potentials (VEP) on the scalp surface is considered for models of horizontally layered media, for models of multilayered concentric media, and for a simulation model based on MR image. The contribution of source location depth is assessed and the sensitivity of the potential to the parameters of the model is calculated. [ABSTRACT FROM AUTHOR]
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- 2025
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5. Altered Use of Context During Visual Perception in Psychotic Psychopathology: A Neurophysiological Investigation of Tuned and Untuned Suppression During Contrast Perception.
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Klein, Samuel D, Teich, Collin D, Pokorny, Victor J, Rawls, Eric, Olman, Cheryl A, and Sponheim, Scott R
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MENTAL orientation ,RESEARCH funding ,NEUROPHYSIOLOGY ,ELECTROENCEPHALOGRAPHY ,VISUAL evoked response ,MENTAL illness ,SCHIZOPHRENIA ,PERCEPTUAL disorders ,VISUAL perception ,PSYCHOSES ,VISUAL acuity ,PATHOLOGICAL psychology - Abstract
Background and Hypothesis The human visual system streamlines visual processing by suppressing responses to textures that are similar to their surrounding context. Surround suppression is weaker in individuals with schizophrenia (ISZ); this altered use of visuospatial context may relate to the characteristic visual distortions they experience. Study Design To understand atypical surround suppression in psychotic psychopathology, we investigated neurophysiological responses in ISZ, healthy controls (HC), individuals with bipolar disorder (IBP), and first-degree relatives (ISZR/IBPR). Participants performed a contrast judgment task on a circular target with annular surrounds, with concurrent electroencephalography. Orientation-independent (untuned) suppression was estimated from responses to central targets with orthogonal surrounds; the orientation-dependence of suppression was estimated by fitting an exponential function to the increase in suppression as surrounds became more aligned with the center. Results ISZ exhibited weakened untuned suppression coupled with enhanced orientation-dependence of suppression. The N1 visual evoked potential was associated with the orientation-dependence of suppression, with ISZ and ISZR (but not IBP or IBPR) showing enhanced orientation-dependence of the N1. Collapsed across orientation conditions, the N1 for ISZ lacked asymmetry toward the right hemisphere; this reduction in N1 asymmetry was associated with reduced untuned suppression, real-world perceptual anomalies, and psychotic psychopathology. The overall amplitude of the N1 was reduced in ISZ and IBP. Conclusions Key measures of symptomatology for ISZ are associated with reductions in untuned suppression. Increased sensitivity for ISZ to the relative orientation of suppressive surrounds is reflected in the N1 VEP, which is commonly associated with higher-level visual functions such as allocation of spatial attention or scene segmentation. [ABSTRACT FROM AUTHOR]
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- 2025
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6. Effect of childhood epilepsy and antiepileptic drugs on visual evoked potential response and optical coherence tomography.
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Moussa, Amira Ahmed, Nassef, Ayman, Nada, Maha A., Karim, Marwa A., Khater, Shaimaa S., and El deen, Nahed Salah
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VISUAL evoked response , *VISUAL evoked potentials , *OPTICAL coherence tomography , *CHILDHOOD epilepsy , *CHILDREN with epilepsy - Abstract
Background: Epileptic seizures arise from an excessively synchronous and sustained discharge of a group of neurons. The single feature of all epileptic syndromes is a persistent increase of neuronal excitability. Visual affection in epileptic children could be attributed to the disease itself or the use of anti-epileptic drugs, these changes may involve abnormal electro-physiological response. This biphasic study, conducted at the neuro-pediatric clinic at neurology department, aimed to investigate effect of idiopathic childhood epilepsy per se on (1) visual evoked potential and (2) optical coherence tomography and effect of selected two antiepileptic medications on them. All subjects were exposed to visual evoked potential and only cooperative subjects exposed to ocular coherence tomography before and after anti-epileptic drugs and were followed up over 2 years. Results: The study included 50 newly diagnosed epileptic children and 50 healthy controls, the mean P100 latency in the right eyes of the control group was 110.4 ± 3.76ms, while in the patients group was 114.94 ± 12.81ms that showed significant difference between the two groups with p value (0.020). After 2 years of treatment by levetiracetam and valproate, the mean P100 latency of the right and left eyes in the valproate group was 112.34 ± 7.05 ms and 112.59 ± 5.2 ms, respectively, and it was 114.85 ± 10.39 ms and 116.14 ± 9.84 ms, respectively, in the valproate group, which showed insignificant difference between the two groups. The mean average of retinal nerve fiber layer thickness between patients and controls was significant in both right and left eyes with p value 0.002 and < 0.001, respectively. After 1 year of treatment by levetiracetam in the first group and valproate in the second group, there was no significant difference between the two groups neither regarding retinal nerve fiber layer thickness nor ganglion cell complex in both eyes. Conclusions: There was prolonged latency in the epileptic children before starting anti-epileptic drugs more than the control group; also there was thinning of the retinal nerve fiber layer thickness and average part of the ganglion cell complex thickness more in the epileptic children than in the healthy controls. [ABSTRACT FROM AUTHOR]
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- 2024
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7. Averted Vision Training to Treat Light Sensitivity of Veterans with a History of TBI.
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Morand, Timothy and Mishler, Pamela
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VISION disorders , *RESEARCH funding , *VISUAL evoked response , *VETERANS , *BRAIN injuries , *VISUAL acuity , *TUBERCULOSIS , *BIOMARKERS , *EYE movements - Abstract
Background: Issues with light sensitivity, especially photophobia, may be reported by nearly half of Veterans with a history of traumatic brain injury (TBI). We designed our innovative approach, known as Averted Vision Training (AVT), to help patients find their way to optimal patterns of fixation that may lead to improvement. Averted vision refers to looking off-center to see faint objects when the eyes are dark adapted, such as viewing a dim star in the night sky. Methods: The study has a mixed-methods design that includes two questionnaires, tests for visual evoked potentials (VEP), and functional assessments with standard contrast sensitivity charts and a microperimeter. Results: Four Veterans with comorbid history of mild or moderate TBI and post-traumatic stress disorder who complained of light sensitivity completed the study. Each was characterized with evidence of brain injury by VEP testing and reported subjective improvement in light sensitivity in response to the training. In exploring microperimetry for objective measure, we found that results for threshold sensitivity were inconclusive, yet results for fixation area were promising. A significant change (enlargement) in the mean fixation area from baseline to posttreatment yielded a large effect size of 1.67, with 55% of the variation attributed to subject performance. These results are suggestive for the use of fixation area as an outcome measure in the rehabilitation of patients with complaints of light sensitivity. Conclusion: As an addition to the basic science of the visual effects of TBI, the potential of having a change in fixation area in response to AVT as an additional valid repeatable testing modality is a substantial strength. If evaluation is left to traditional clinical tests of fixation and light sensitivity, then the opportunity to identify and benefit these Veterans may be missed. [ABSTRACT FROM AUTHOR]
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- 2024
8. Detecting and Addressing Secondary Neural Injuries in Cranial Surgery: Case Report.
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Silverstein, Justin W., Duehr, James, Vilaysom, Sabena, Schulder, Michael, and Eichberg, Daniel G.
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BRAIN injury treatment , *NEUROSURGERY , *BODY mass index , *VISION disorders , *SOMATOSENSORY evoked potentials , *EVOKED potentials (Electrophysiology) , *ELECTROENCEPHALOGRAPHY , *VISUAL evoked response , *TREMOR , *MAGNETIC resonance imaging , *CRANIOTOMY , *MUSCLE weakness , *ELECTROMYOGRAPHY , *BRAIN surgery , *HAND , *MENINGIOMA , *BRAIN injuries , *SKULL , *MEMORY disorders - Abstract
Intraoperative neurophysiological monitoring (IONM) is instrumental in mitigating neurological deficits following cranial and spinal procedures. Despite extensive research on IONM's ability to recognize limb-malposition-related issues, less attention has been given to other secondary neural injuries in cranial surgeries. A comprehensive multimodal neuromonitoring approach was employed during a left frontal craniotomy for tumor resection. The electronic medical record was reviewed in detail in order to describe the patient's clinical course. The patient, a 46-year-old female, underwent craniotomy for excision of a meningioma. Deteriorations in somatosensory evoked potential and transcranial motor evoked potential recordings identified both a mal-positioned limb as well as an infiltrated intravenous (IV) line in the arm contralateral to the surgical site. The IONM findings for the infiltrated IV were initially attributed to potential limb malposition until swelling and blistering of the limb were appreciated and investigated. The timely identification and management of the infiltrated IV and adjustment of limb positioning contributed to the patient's recovery, avoiding fasciotomy, with no postoperative neurological deficits. This case is the first published demonstration of the utility of IONM in detecting IV infiltration. This early recognition facilitated early intervention, saving the patient from a potential fasciotomy and enabling their recovery with no postoperative neurological deficits. The findings from this single case highlight the necessity for vigilant and dynamic application of IONM techniques to enhance patient safety and outcomes in neurosurgical procedures. Further research is needed to explore broader applications and further optimize the detection capabilities of IONM. [ABSTRACT FROM AUTHOR]
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- 2024
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9. Anticipatory and evoked visual cortical dynamics of voluntary temporal attention.
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Denison, Rachel N., Tian, Karen J., Heeger, David J., and Carrasco, Marisa
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VISUAL evoked response ,GOAL (Psychology) ,VISUAL perception ,MAGNETOENCEPHALOGRAPHY ,EXPECTATION (Psychology) - Abstract
We can often anticipate the precise moment when a stimulus will be relevant for our behavioral goals. Voluntary temporal attention, the prioritization of sensory information at task-relevant time points, enhances visual perception. However, the neural mechanisms of voluntary temporal attention have not been isolated from those of temporal expectation, which reflects timing predictability rather than relevance. Here we use time-resolved steady-state visual evoked responses (SSVER) to investigate how temporal attention dynamically modulates visual activity when temporal expectation is controlled. We recorded magnetoencephalography while participants directed temporal attention to one of two sequential grating targets with predictable timing. Meanwhile, a co-localized SSVER probe continuously tracked visual cortical modulations both before and after the target stimuli. We find that in the pre-target period, the SSVER gradually ramps up as the targets approach, reflecting temporal expectation. Furthermore, we find a low-frequency modulation of the SSVER, which shifts approximately half a cycle in phase according to which target is attended. In the post-target period, temporal attention to the first target transiently modulates the SSVER shortly after target onset. Thus, temporal attention dynamically modulates visual cortical responses via both periodic pre-target and transient post-target mechanisms to prioritize sensory information at precise moments. People can direct attention to specific moments that they anticipate will be relevant to their goals. Here, the authors show that voluntary temporal attention engages both periodic and transient modulations of visual cortical activity to improve perception at precise time points. [ABSTRACT FROM AUTHOR]
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- 2024
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10. Neurochemistry and functional connectivity in the brain of people with Charles Bonnet syndrome.
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Bridge, Holly, Wyllie, Abigail, Kay, Aaron, Rand, Bailey, Starling, Lucy, Millington-Truby, Rebecca S., Clarke, William T., Jolly, Jasleen K., and Ip, I. Betina
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GABA antagonists ,CROSS-sectional method ,FUNCTIONAL connectivity ,VISION disorders ,NUCLEAR magnetic resonance spectroscopy ,RESEARCH funding ,BRAIN ,VISUAL evoked response ,SCIENTIFIC observation ,OCCIPITAL lobe ,BIOCHEMISTRY ,MAGNETIC resonance imaging ,CHARLES Bonnet syndrome ,HALLUCINATIONS ,LONGITUDINAL method ,CASE-control method ,VISUAL perception ,VISUAL acuity ,BRAIN mapping ,COGNITION - Abstract
Background: Charles Bonnet syndrome (CBS) is a condition in which people with vision loss experience complex visual hallucinations. These complex visual hallucinations may be caused by increased excitability in the visual cortex that are present in some people with vision loss but not others. Objectives: We aimed to evaluate the association between γ-aminobutyric acid (GABA) in the visual cortex and CBS. We also tested the relationship among visually evoked responses, functional connectivity, and CBS. Design: This is a prospective, case-controlled, cross-sectional observational study. Methods: We applied 3-Tesla magnetic resonance spectroscopy, as well as task-based and resting state (RS) connectivity functional magnetic resonance imaging in six participants with CBS and six controls without CBS. GABA+ was measured in the early visual cortex (EVC) and in the lateral occipital cortex (LOC). Participants also completed visual acuity and cognitive tests, and the North-East Visual Hallucinations Interview. Results: The two groups were well-matched for age, gender, visual acuity and cognitive scores. There was no difference in GABA+ levels between groups in the visual cortex. Most participants showed the expected blood oxygenation level dependent (BOLD) activation to images of objects and the phase-scrambled control. Using a fixed effects analysis, we found that BOLD activation was greater in participants with CBS compared to controls. Analysis of RS connectivity with LOC and EVC showed little difference between groups. A fixed effects analysis showed a correlation between the extent of functional connectivity with LOC and hallucination strength. Conclusion: Overall, our results provide no strong evidence for an association between GABAergic inhibition in the visual cortex and CBS. We only found subtle differences in visual function and connectivity between groups. These findings suggest that the neurochemistry and visual connectivity for people with Charles Bonnet hallucinations are comparable to a sight loss population. Differences between groups may emerge when investigating subtle and transient changes that occur at the time of visual hallucinations. Plain language summary: Brain imaging in Charles Bonnet syndrome In Charles Bonnet Syndrome (CBS), people with sight loss start to see hallucinations that they know are not real but can be disturbing. In this study we used MRI scanning to measure how the chemistry in the visual brain differs in people with CBS and those who have sight loss but no hallucinations. Surprisingly we did not find any differences in chemistry between these groups, suggesting that their brains do not differ greatly. Any differences in how their visual brain works may be too small to measure, or only present when people hallucinate. [ABSTRACT FROM AUTHOR]
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- 2024
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11. Development and Standardization of Modified Simultaneous Multifrequency Stimulus for Recording Ocular Vestibular-Evoked Myogenic Potential and Its Interaction with the Alternate Electrode Montages.
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Raveendran, Rajesh Kumar and Singh, Niraj Kumar
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SUPERIOR semicircular canal dehiscence syndrome , *EVOKED potentials (Electrophysiology) , *VISUAL evoked response , *DESCRIPTIVE statistics , *ACOUSTIC stimulation , *COMPARATIVE studies , *ELECTRODES - Abstract
Background Simultaneous multifrequency (SiMFy) is a time-saving and reliable stimulus to determine the frequency tuning of ocular vestibular-evoked myogenic potential (oVEMP); however, the absence of 4000 Hz in SiMFy potentially makes it a less potent tool for the diagnosis of superior semicircular canal dehiscence, a pathology with an ever-increasing prevalence. Further, SiMFy was validated using only the infraorbital (IO) electrode montage. However, the recordings obtained using the IO montage might be susceptible to reference contamination introduced by a small separation between the recording electrodes and also susceptible to reflex impurity due to the spatially displaced reference electrode from the inferior oblique muscle, rendering it vulnerable to picking up responses from other muscles. Nonetheless, little is known about the similarities/differences between the SiMFy-induced oVEMPs using alternate montages (belly-tendon [BT], chin-reference [CR], and sternum-reference [SR]) and the nonsimultaneous multifrequency oVEMPs (NSM-oVEMPs) using the IO montage. Purpose of the Study To develop a modified SiMFy stimulus and investigate its effects on frequency tuning of oVEMP using various electrode montages. Research Design Within-subject experimental design. Study Sample Thirty-three healthy adults aged 20 to 30 years. Data Collection and Analysis Tone bursts of octave and mid-octave frequencies from 250 to 4000 Hz were generated and concatenated to create the modified SiMFy stimulus. All participants underwent NSM oVEMPs and modified SiMFy oVEMPs using BT, CR, SR, and IO montages simultaneously. The response rate, peak-to-peak amplitude, and frequency tuning were compared between NSM-oVEMP and modified SiMFy oVEMP and also between the electrode montages. Results BT montage recorded the largest amplitude among the montages in NSM stimulation and modified SiMFy stimulation. Although the response rates were comparable, the modified SiMFy produced significantly lower oVEMP amplitudes than the NSM stimulation within each electrode montage (p < 0.05). A moderate-to-strong agreement on frequency tuning existed between the NSM stimuli and modified SiMFy stimulus for all the montages, except for the SR montage. Conclusions Although the modified SiMFy produces smaller amplitude oVEMPs than the NSM stimulation for the respective montages, its use in combination with the BT montage yields higher response rates and larger peak-to-peak amplitudes than the NSM recording using IO montage. [ABSTRACT FROM AUTHOR]
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- 2024
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12. Optic Nerve Hypoplasia – Case Report.
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Lestak, Jan, Prazakova, Lenka, Fus, Martin, and Kyncl, Martin
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VISUAL evoked response ,MAGNETIC resonance imaging ,FUNDUS oculi ,OPTIC nerve ,VISUAL fields - Abstract
The case report of a young myope (born in 1997) who was diagnosed with bilateral concentric narrowing of the visual field to 15– 20 degrees in 2021 is presented. On eye fundus, the findings were normal with central excavation c/d=0.5 and 0.4, respectively. OCT showed loss of retinal nerve fiber layer – in both vertical quadrants, including a reduction in the ganglion cell complex. Electrophysiological examination (PERG) showed normal retinal responses. Visual evoked responses (PVEP) after stimulation squared a 1 degree decrease in amplitudes, with no prolongation of P100 latency. When stimulated with 15-minute squares, responses were normal (see Supplementary Figure). Magnetic resonance imaging of the brain showed a narrowing of the chiasm. In conclusion, optic chiasm hypoplasia may not always have distinct morphological and functional manifestations. In addition to imaging methods, electrophysiological examination of the visual analyser was of great help for its verification. [ABSTRACT FROM AUTHOR]
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- 2024
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13. Ocular manifestations of multiple sclerosis: This article outlines the systemic and ocular manifestations of multiple sclerosis to help practitioners identify these cases in practice.
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Ebraheem, Adel and Smith-Jaynes, Ceri
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CENTRAL nervous system , *VISUAL evoked response , *MYELIN oligodendrocyte glycoprotein , *OPTIC nerve diseases , *NERVOUS system , *VISUAL fields , *OPTIC neuritis , *LOW vision - Published
- 2024
14. Excitability Changes in Occipital Cortex After Continuous Theta-Burst Stimulation.
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Aghamirzayeva, Khayala, Temuçin, Çağrı Mesut, and Yıldız, Fatma Gökçem
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OCCIPITAL lobe , *VISUAL evoked response , *NEUROPHYSIOLOGY , *QUESTIONNAIRES , *MAGNETOTHERAPY , *TRANSCRANIAL magnetic stimulation - Abstract
Introduction: Modulation of visual cortical structures by repetitive transcranial magnetic stimulation is rarely observed in literature. In this study; the researchers aimed to investigate the neurophysiological alterations by using continuous theta burst stimulation (cTBS) protocol over the occipital cortex in healthy subjects. Methods: Twenty-five (15 female, 10 male) (mean age 29.84±4.7 years) healthy individuals were included in sham and real cTBS occipital stimulation sessions. Before and after each session, neurophysiological studies including phosphene threshold and visual evoked potential (VEP) responses were recorded. The P100 latency values and maximum amplitude values between N75-P100 peaks of 100 responses of 1000 uninterrupted continuous visual stimuli were measured. The VEP habituation and phosphene thresholds were compared in sham and real cTBS sessions. Results: The phosphene threshold values increased to statistically significant levels after the real cTBS session. Visual evoked potential habituation was observed in both sham and real cTBS sessions in individuals without significant differences. Also, no difference between the P100 latencies and N75-P100 amplitude values in the sham and real cTBS sessions was observed. Conclusion: Phosphene threshold measurements demonstrated the modulation of the occipital cortex excitability via cTBS in healthy subjects. [ABSTRACT FROM AUTHOR]
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- 2024
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15. Reduced Visual Evoked Potential Amplitude in Autistic Children with Co-Occurring Features of Attention-Deficit/Hyperactivity Disorder.
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Cremone-Caira, Amanda, Braverman, Yael, MacNaughton, Gabrielle A., Nikolaeva, Julia I., and Faja, Susan
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ATTENTION-deficit hyperactivity disorder , *RESEARCH funding , *DATA analysis , *VISUAL evoked response , *AUTISM , *ELECTROENCEPHALOGRAPHY , *DESCRIPTIVE statistics , *CASE-control method , *ANALYSIS of variance , *STATISTICS , *ASPERGER'S syndrome , *COMPARATIVE studies , *INTELLIGENCE tests , *COMORBIDITY , *CHILDREN - Abstract
Provided the significant overlap in features of autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD), there is a critical need to identify transdiagnostic markers that could meaningfully stratify subgroups. The objective of this study was to compare the visual evoked potential (VEP) between 30 autistic children, 17 autistic children with co-occurring ADHD presentation (ASD + ADHD), and 21 neurotypical children (NTC). Electroencephalography was recorded while children passively viewed a pattern-reversal stimulus. Mean amplitude of the P1 event-related potential was extracted from a midline occipital channel and compared between groups. P1 mean amplitude was reduced in the ASD + ADHD group compared to the ASD and NTC groups, indicating a distinct pattern of brain activity in autistic children with co-occurring ADHD features. [ABSTRACT FROM AUTHOR]
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- 2024
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16. Successful treatment of cortical visual impairment in children using anti-amblyopia treatment despite the absence of amblyopia: a case report.
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Sica, Attilio, Michieletto, Paola, Pensiero, Stefano, and Barbi, Egidio
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CEREBRAL anoxia-ischemia , *EARLY medical intervention , *REFRACTIVE errors , *VISUAL evoked response , *BRAIN , *TREATMENT effectiveness , *STRABISMUS , *FUNCTIONAL status , *MAGNETIC resonance imaging , *CEREBRAL cortex , *CORTICAL blindness , *APRAXIA , *VOCATIONAL rehabilitation , *CONVALESCENCE , *AMBLYOPIA , *VISUAL acuity , *DISEASE complications , *CHILDREN - Abstract
Background: Cortical visual impairment (CVI) is a verifiable visual dysfunction that cannot be attributed to disorders of the anterior visual pathways or any potentially co-occurring ocular impairment. Given the limited knowledge on the most effective interventions for visual impairment resulting from CVI, this case report provides valuable insights into an example of successful implementation of anti-amblyopia therapy in a patient with CVI. Case presentation: This case report presents a 5-year-old girl with CVI secondary to hypoxic-ischemic injury, resulting in visual impairment, dyspraxia, and abnormal visual evoked potential testing. The girl did not suffer from amblyopia, there was no evidence of relevant refractive errors or strabismus, so visual pathway damage was the cause of her visual deficit. Nevertheless, the patient underwent anti-amblyopia therapy and showed significant improvement in visual acuity after 12 months of treatment. The improvement, resulting from visual stimulation, was due to a good functional recovery by a better usage of the damaged visual pathways. The therapy included prescribing corrective glasses and implementing secondary occlusion of the better eye for 4 months, which was protracted for another 4 months, leading to further improvements in visual acuity. Conclusions: The case report shows that addressing even minor refractive errors and implementing anti-amblyopia therapy can significantly improve vision in children with CVI, even without co-existing amblyopia. It also highlights the importance of early intervention and multidisciplinary rehabilitation in children with CVI, focusing on motor and cognitive skills. Additionally, it emphasizes the need for further research to establish evidence-based practice standards for improving vision in children with CVI. [ABSTRACT FROM AUTHOR]
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- 2024
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17. Optic Neuritis with Unilateral Superior Altitudinal Visual Field Defect in Multiple Sclerosis: A Case Report.
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Maghbooli, Mehdi, Afshari, Shahram, and Alan, Mahin Seifi
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PHYSIOLOGY of the anatomical extremities ,MULTIPLE sclerosis diagnosis ,VISION disorders ,MULTIPLE sclerosis ,HEADACHE ,VISUAL evoked response ,COMPUTED tomography ,MAGNETIC resonance imaging ,PREDNISOLONE ,TREATMENT effectiveness ,OPTIC neuritis ,NUMBNESS ,VISUAL fields ,METHYLPREDNISOLONE ,EYE movements ,SYMPTOMS - Abstract
We describe an exceptional instance of multiple sclerosis manifesting in a unilateral, superior visual field deficit accompanied by painful eye movements. A 16-year-old girl with no prior health issues presented with symptoms of blurred vision, ocular pain in eye movement, and a throbbing headache in her right eye. She experienced right-sided numbness for two weeks, which later affected her left limbs. Effective management of multiple sclerosis necessitates familiarity with its uncommon presentations due to the significance of early diagnosis and treatment. Unilateral superior altitudinal visual field defect, orbital pain upon eye movement, and left hemi-paresthesia may be an uncommon presenting symptom in MS patients. After completing treatment with methylprednisolone, visual acuity can improve completely. [ABSTRACT FROM AUTHOR]
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- 2024
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18. Label-free photoacoustic computed tomography of visually evoked responses in the primary visual cortex and four subcortical retinorecipient nuclei of anesthetized mice.
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Kai-Wei Chang, Xueding Wang, Wong, Kwoon Y., and Guan Xu
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VISUAL evoked response ,LATERAL geniculate body ,VISION ,SUPERIOR colliculus ,COMPUTED tomography - Abstract
Significance: Many techniques exist for screening retinal phenotypes in mouse models in vision research, but significant challenges remain for efficiently probing higher visual centers of the brain. Photoacoustic computed tomography (PACT), with optical sensitivity to hemodynamic response (HR) in brain and ultrasound resolution, provides unique advantages in comprehensively assessing higher visual function in the mouse brain. Aim: We aim to examine the reliability of PACT in the functional phenotyping of mouse models for vision research. Approach: A PACT-ultrasound (US) parallel imaging system was established with a one-dimensional (1D) US transducer array and a tunable laser. Imaging was performed at three coronal planes of the brain, covering the primary visual cortex and the four subcortical nuclei, including the superior colliculus, the dorsal lateral geniculate nucleus, the suprachiasmatic nucleus, and the olivary pretectal nucleus. The visual-evoked HR was isolated from background signals using an impulsebased data processing protocol. rd1 mice with rod/cone degeneration, melanopsinknockout (mel-KO) mice with photoreceptive ganglion cells that lack intrinsic photosensitivity, and wild-type mice as controls were imaged. The quantitative characteristics of the visual-evoked HR were compared. Results: Quantitative analysis of the HRs shows significant differences among the three mouse strains: (1) rd1 mice showed both smaller and slower responses compared with wild type (n = 10;10, p < 0.01) and (2) mel-KO mice had lower amplitude but not significantly delayed photoresponses than wild-type mice (n = 10;10, p < 0.01). These results agree with the known visual deficits of the mouse strains. Conclusions: PACT demonstrated sufficient sensitivity to detecting post-retinal functional deficits. [ABSTRACT FROM AUTHOR]
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- 2024
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19. Why Objective?
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Ciuffreda, Kenneth J., Tannen, Barry, and Rutner, Daniella
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VERTIGO , *VISION disorders , *EYE movement measurements , *VISUAL evoked response , *OPTOMETRISTS , *BIOMETRY , *BRAIN injuries , *EYE movements , *DIPLOPIA - Published
- 2024
20. A comparative study of visual evoked potential parameters in type 2 diabetes mellitus patients with increasing duration.
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Tiwari, Ritu, Dubey, Namrata, and Budholia, Prabhat Kumar
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TYPE 2 diabetes ,VISUAL evoked potentials ,PEOPLE with diabetes ,AUDITORY evoked response ,VISUAL evoked response ,PANCREATIC beta cells - Published
- 2024
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21. Delineating Visual Habituation Profiles in Preschoolers with Neurofibromatosis Type 1 and Autism Spectrum Disorder: A Cross-Syndrome Study.
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Hocking, Darren R., Sun, Xiaoyun, Haebich, Kristina, Darke, Hayley, North, Kathryn N., Vivanti, Giacomo, and Payne, Jonathan M.
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VISUAL evoked response , *AUTISM , *NEUROFIBROMATOSIS 1 , *VISUAL perception , *EYE movements , *COGNITION , *CHILDREN - Abstract
Atypical habituation to repetitive information has been commonly reported in Autism Spectrum Disorder (ASD) but it is not yet clear whether similar abnormalities are present in Neurofibromatosis Type 1 (NF1). We employed a cross-syndrome design using a novel eye tracking paradigm to measure habituation in preschoolers with NF1, children with idiopathic ASD and typically developing (TD) children. Eye movements were recorded to examine fixation duration to simultaneously presented repeating and novel stimuli. Children with NF1 showed a bias for longer look durations to repeating stimuli at the expense of novel stimuli, and slower habituation in NF1 was associated with elevated ASD traits. These findings could indicate aberrant modulation of bottom-up attentional networks that interact with the emergence of ASD phenotypes. [ABSTRACT FROM AUTHOR]
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- 2024
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22. Molecular Engineering Technology for Studying and Treating the Brain.
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Szablowski, Jerzy
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NANOTECHNOLOGY ,BIOENGINEERING ,RECOMBINANT proteins ,BLOOD-brain barrier ,ULTRASOUND contrast media ,VISUAL evoked response ,GENETIC vectors ,DOPAMINE receptors - Abstract
The article focuses on engineering innovative solutions for treating brain disorders, emphasizing the challenges of therapy development and the potential of molecular engineering and noninvasive delivery methods, like focused ultrasound, for precise treatment. It also highlights the importance of developing monitoring technologies, such as synthetic serum markers, to evaluate therapy effectiveness.
- Published
- 2024
23. Neuronal Modeling of Cross-Sensory Visual Evoked Magnetoencephalography Responses in the Auditory Cortex.
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Lankinen, Kaisu, Ahveninen, Jyrki, Jas, Mainak, Raij, Tommi, and Ahlfors, Seppo P.
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AUDITORY cortex , *VISUAL evoked response , *AUDITORY evoked response , *AUDITORY perception , *VISUAL perception - Abstract
Previous studies have demonstrated that auditory cortex activity can be influenced by cross-sensory visual inputs. Intracortical laminar recordings in nonhuman primates have suggested a feedforward (FF) type profile for auditory evoked but feedback (FB) type for visual evoked activity in the auditory cortex. To test whether cross-sensory visual evoked activity in the auditory cortex is associated with FB inputs also in humans, we analyzedmagnetoencephalography (MEG) responses fromeight human subjects (six females) evoked by simple auditory or visual stimuli. In the estimatedMEG source waveforms for auditory cortex regions of interest, auditory evoked response showed peaks at 37 and 90 ms and visual evoked response at 125 ms. The inputs to the auditory cortex were modeled through FF- and FB-type connections targeting different cortical layers using the Human Neocortical Neurosolver (HNN), which links cellular- and circuit- level mechanisms toMEG signals. HNN modeling suggested that the experimentally observed auditory response could be explained by an FF input followed by an FB input, whereas the cross-sensory visual response could be adequately explained by just an FB input. Thus, the combined MEG and HNN results support the hypothesis that cross-sensory visual input in the auditory cortex is of FB type. The results also illustrate how the dynamic patterns of the estimated MEG source activity can provide information about the characteristics of the input into a cortical area in terms of the hierarchical organization among areas. [ABSTRACT FROM AUTHOR]
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- 2024
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24. Psychophysical, electrofunctional, and morphological evaluation in naïve neovascular AMD patients treated with intravitreal anti‐VEGF.
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Nebbioso, Marcella, Franzone, Federica, Milanese, Alberto, Artico, Marco, Taurone, Samanta, La Cava, Maurizio, Livani, Maria Luisa, Bonfiglio, Vincenza, and Vestri, Annarita
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RETINA physiology ,RETINAL anatomy ,VASCULAR endothelial growth factor antagonists ,PSYCHOPHYSIOLOGY ,DATA analysis ,RETINAL degeneration ,INTRAVITREAL injections ,OPTICAL coherence tomography ,VISUAL evoked response ,SCIENTIFIC observation ,VISION testing ,NEOVASCULARIZATION inhibitors ,TREATMENT effectiveness ,DESCRIPTIVE statistics ,LONGITUDINAL method ,RECOMBINANT proteins ,RESEARCH ,FRIEDMAN test (Statistics) ,STATISTICS ,PATHOLOGIC neovascularization ,VISUAL acuity ,CONFIDENCE intervals ,ELECTROPHYSIOLOGY ,EVALUATION - Abstract
Objectives: The aim of this study was to investigate the retinal morpho‐functional characteristics of patients with neovascular wet age‐related macular degeneration (nAMD) treated with intravitreal injection (IV) of aflibercept (AFL). Methods: The study was conducted on 35 patients previously diagnosed with type 1 nAMD who received a fixed‐dosing regimen of aflibercept injections over 12 months. The goal was to assess trends in visual abilities over time by measuring visual acuity (VA), contrast sensitivity (CS), visual evoked potentials (VEPs), and spectral domain‐optical coherence tomography (SD‐OCT). The same psychophysical, electro‐functional, and morphological tests administered at baseline (T0) were repeated 4 to 8 weeks after the last aflibercept injection (Tn), resulting in a total of six examinations. Results: At Tn, all subjects exhibited improved VA for both far and near distances compared to values detected at T0. Similarly, VEP amplitude and latency values at Tn showed a greater P100 improvement than those observed at T0. Additionally, the CS examination at Tn demonstrated improvement, particularly at high spatial stimulation frequencies. The Tn SD‐OCT results highlighted a reduction in macular thickness compared to T0 values. Conclusions: This exploratory research indicates that intravitreal injections of AFL, following a fixed‐dosing regimen, represent a valuable therapeutic approach for enhancing visual performance. This conclusion is supported by comprehensive statistical analysis of psychophysical, electro‐functional, and morphological examinations within the same group of patients with nAMD, as demonstrated for the first time. [ABSTRACT FROM AUTHOR]
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- 2024
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25. Clinical characteristics of Vogt-Koyanagi-Harada syndrome combing with meningitis/encephalitis.
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PENG Yu-jing, SHI Xiao-hong, and WANG Jia-wei
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RETINAL detachment ,INTRAVENOUS immunoglobulins ,OPTIC nerve ,MENINGITIS ,HEADACHE ,BRAIN ,VISUAL evoked response ,OPTICAL coherence tomography ,MAGNETIC resonance imaging ,ENCEPHALITIS ,DEMYELINATION ,EARLY diagnosis ,CEREBROSPINAL fluid ,SYMPTOMS - Abstract
Objective To summarize the clinical characteristics of Vogt-Koyanagi-Harada syndrome (VKHS) combing with meningitis/encephalitis patients. Methods and Results The clinical data of the inpatients of Beijing Tongren Hospital, Capital Medical University from January 2009 to December 2022 with VKHS combing with meningitis/encephalitis were retrospectively analyzed. A total of 23 patients were included in the study, of which 20 patients (86.96%) had neurological symptoms, with headache being the most common (19 cases, 82.61%), 11 patients (47.83%) had increased cerebrospinal fluid (CBF) pressure, 14 patients (60.87%) had increased CBF white blood cells, and 11 patients (47.83%) had increased CBF protein. The brain MRI mainly showed white matter demyelination (8/14 cases). Optic nerve MRI showed inflammatory lesions of optic nerve and optic papilla (12/14 cases). The visual evoked potential (VEP) mainly showed prolonged latency (10/16 cases). The optical coherence tomography (OCT) showed retinal exudation (8/15 cases) and retinal neurocortical detachment (7/15 cases). The main results of fundus photography were disc edema (17/18 cases). The main manifestation of fundus fluorescein angiography (FFA) was uveitis (9/15 cases). After intravenous hormone and intravenous immunoglobulin (IVIg) treatment, 14 patients were followed up, and neurological symptoms were completely relieved, 11 patients had good visual prognosis, and 3 patients had no obvious visual improvement. Conclusions VKHS might present with meningitis/encephalitis symptoms, and the CSF characteristics of these patients were similar to those of viral meningitis. For those with early suspicions of VKHS, CBF examination and imaging examination might assist in early diagnosis and treatment. [ABSTRACT FROM AUTHOR]
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- 2024
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26. Face Processing in ADHD: A Review of the N170 Event-Related Potential.
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Roberts, Brady R. T. and Trossman, Rebecca
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BIOMARKERS , *SOCIAL perception , *SYSTEMATIC reviews , *FACE perception , *ATTENTION-deficit hyperactivity disorder , *INTERPERSONAL relations , *SOCIAL skills , *VISUAL evoked response - Abstract
Attention-deficit hyperactivity disorder (ADHD) is associated with deficits in social functioning, including peer difficulties and poor relationship quality. Little is known, however, about the integrity of foundational sociocognitive abilities that support interpersonal interactions in ADHD. Face processing--a fundamental component of social cognition--has been a popular topic of recent investigations in this area. Researchers have attempted to delineate face processing mechanisms in ADHD to elucidate social deficits often seen in the disorder. Investigating the N170 event-related potential, a neural marker of face processing, has been a popular approach in this endeavour. Here, we present two accounts that offer competing views of how social deficits might arise in those with ADHD. Next, we systematically review and synthesise the literature on the N170 in ADHDto identify whether atypicalities in sociocognitive domains like face processing occur in this patient population. Gaps in the literature are identified and concrete solutions are offered to improve future research in this area. We end by discussing immediate implications for treatment approaches designed to address widely observed social deficits in individuals with ADHD. [ABSTRACT FROM AUTHOR]
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- 2024
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27. Application of remimazolam-0.6% sevoflurane anesthesia for flash visual evoked potential monitoring during pituitary adenoma resection: a non-inferiority randomized controlled trial.
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Shi, Fu, Tang, Ranran, Du, Xiangrong, Li, Xin, and Wu, Guisheng
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PROPOFOL , *DRUG efficacy , *STATISTICAL power analysis , *GENERAL anesthesia , *CLINICAL trials , *CONFIDENCE intervals , *NAUSEA , *ANESTHETICS , *DIZZINESS , *MANN Whitney U Test , *FISHER exact test , *SURGICAL complications , *COMPARATIVE studies , *T-test (Statistics) , *VOMITING , *PITUITARY tumors , *SEVOFLURANE , *DESCRIPTIVE statistics , *CHI-squared test , *INTRAOPERATIVE monitoring , *STATISTICAL sampling , *HEMODYNAMICS , *DATA analysis software , *ADVERSE health care events , *VISUAL evoked response , *LONGITUDINAL method , *ELECTRORETINOGRAPHY , *ADULTS - Abstract
Background: Flash visual evoked potential (FVEP) is a critical method for monitoring intraoperative visual function during neurosurgery. A new benzodiazepine drug called remimazolam has recently been used for general anesthesia. However, the impact of remimazolam on FVEP remains unclear. Therefore, we aimed to investigate how remimazolam, in comparison to propofol, when combined with 0.6% sevoflurane anesthesia, affects the FVEP waveform during pituitary adenoma resection. Methods: Overall, 36 patients undergoing pituitary adenoma resection under general anesthesia were randomly assigned to either the remimazolam group (Group R) or the propofol group (Group P) in a prospective, randomized, controlled, non-inferiority trial. For anesthesia induction, a bolus of 0.2 mg/kg remimazolam or 2 mg/kg propofol was intravenously infused for approximately one minute. The anesthesia was maintained by continuous infusion of either remimazolam (0.7-1.0 mg/kg/h) or propofol (4–6 mg/kg/h), in combination with 0.6% sevoflurane, aimed at sustaining the bispectral index (BIS) within the range of 40–60. The primary outcome was the N75-P100 amplitude of FVEP recorded at approximately 20 min after intubation (T0). 10% of the amplitude at T0 in group P was defined as the non-inferiority margin (δ). Confidence interval testing was used to evaluate the non-inferiority hypothesis. The secondary outcomes covered the P100 latency of FVEP, electroretinogram (ERG) b wave amplitude, demographic characteristics, hemodynamics, and occurrence of adverse events. Results: The BIS index during anesthesia was comparable between the groups at the same measured time points (P > 0.05). The N75-P100 amplitude at T0 in group R was 7.64 ± 1.36 µV, while it was 6.96 ± 0.95 µV in group P (P = 0.09), with a mean difference of 0.68 µV (95% CI, -0.11 µV to 1.48 µV). The δ was set at 0.7 and the lower limit of the 95% CI exceeded the -δ. Both remimazolam and propofol had little effect on ERG b-wave amplitudes. At the designated time points, FVEP amplitude and P100 latency displayed no appreciable variation between the two groups (P > 0.05). Furthermore, there were no significant differences in the incidence of adverse events related to anesthesia, needle electrodes, or surgery between the two groups (P > 0.05). Conclusion: Our findings suggest that remimazolam-0.6% sevoflurane is non-inferior to propofol-0.6% sevoflurane for general anesthesia, based on the FVEP N75-P100 amplitude. The electrophysiological data obtained in both groups indicate that reproducible and stable FVEP and ERG waveforms can be acquired at set time points. Therefore, for reliable FVEP monitoring, remimazolam-0.6% sevoflurane appears to be a safe and effective protocol in general anesthesia. Trials registration: This study was registered on chictr.org.cn (ChiCTR2200056803, 17/02/2022). [ABSTRACT FROM AUTHOR]
- Published
- 2024
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28. Computational methodology to support functional vision assessment in premature infants: A viability study.
- Author
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Maciel, Ricardo Pires, Marchi, Bruna Samantha, Silveira, Henrique da Silva da, Rodovanski, Giovana Pascoali, Al-Rob, Aicha, Souza, Rodrigo, Costa, Marcelo Fernandes, Moran, Cristiane Aparecida, and Sobieranski, Antonio Carlos
- Subjects
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NEWBORN screening , *COMPUTERS , *DATA analysis , *RESEARCH funding , *HIGH performance computing , *VISION testing , *VISUAL evoked response , *PILOT projects , *IRIS (Eye) , *DESCRIPTIVE statistics , *EXPERIMENTAL design , *SOFTWARE architecture , *VISUAL perception , *VISUAL fields , *COMPARATIVE studies , *DATA analysis software , *FACE perception , *EYE movements , *ALGORITHMS , *CHILDREN - Abstract
BACKGROUND: Premature newborns have a higher risk of abnormal visual development and visual impairment. OBJECTIVE: To develop a computational methodology to help assess functional vision in premature infants by tracking iris distances. METHODS: This experimental study was carried out with children up to two years old. A pattern of image capture with the visual stimulus was proposed to evaluate visual functions of vertical and horizontal visual tracking, visual field, vestibulo-ocular reflex, and fixation. The participants' visual responses were filmed to compose a dataset and develop a detection algorithm using the OpenCV library allied with FaceMesh for the detection and selection of the face, detection of specific facial points and tracking of the iris positions is done. A feasibility study was also conducted from the videos processed by the software. RESULTS: Forty-one children of different ages and diagnoses participated in the experimental study, forming a robust dataset. The software resulted in the tracking of iris positions during visual function evaluation stimuli. Furthermore, in the feasibility study, 8 children participated, divided into Pre-term and Term groups. There was no statistical difference in any visual variable analyzed in the comparison between groups. CONCLUSION: The computational methodology developed was able to track the distances traveled by the iris, and thus can be used to help assess visual function in children. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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29. Distinct patterns of spatial attentional modulation of steady‐state visual evoked magnetic fields (SSVEFs) in subdivisions of the human early visual cortex.
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Moratti, Stephan, Gundlach, Christopher, de Echegaray, Javier, and Müller, Matthias M.
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VISUAL cortex , *VISUAL evoked response , *VISUAL evoked potentials , *MAGNETIC fields , *BRAIN-computer interfaces - Abstract
In recent years, steady‐state visual evoked potentials (SSVEPs) became an increasingly valuable tool to investigate neural dynamics of competitive attentional interactions and brain–computer interfaces. This is due to their good signal‐to‐noise ratio, allowing for single‐trial analysis, and their ongoing oscillating nature that enables to analyze temporal dynamics of facilitation and suppression. Given the popularity of SSVEPs, it is surprising that only a few studies looked at the cortical sources of these responses. This is in particular the case when searching for studies that assessed the cortical sources of attentional SSVEP amplitude modulations. To address this issue, we used a typical spatial attention task and recorded neuromagnetic fields (MEG) while presenting frequency‐tagged stimuli in the left and right visual fields, respectively. Importantly, we controlled for attentional deployment in a baseline period before the shifting cue. Subjects either attended to a central fixation cross or to two peripheral stimuli simultaneously. Results clearly showed that signal sources and attention effects were restricted to the early visual cortex: V1, V2, hMT+, precuneus, occipital‐parietal, and inferior‐temporal cortex. When subjects attended to central fixation first, shifting attention to one of the peripheral stimuli resulted in a significant activation increase for the to‐be‐attended stimulus with no activation decrease for the to‐be‐ignored stimulus in hMT+ and inferio‐temporal cortex, but significant SSVEF decreases from V1 to occipito‐parietal cortex. When attention was first deployed to both rings, shifting attention away from one ring basically resulted in a significant activation decrease in all areas for the then‐to‐be‐ignored stimulus. Although the cortical generators of steady‐state visual evoked responses as recorded by EEG or MEG (SSVEPs or SSVEFs, respectively) have been described in humans, how these generators are involved in the modulation of these evoked oscillatory responses by spatial attention is less known. Here, we describe how distinct sub‐divisions of the early human visual cortex contribute differently to the modulation of SSVEFs by spatial attention. [ABSTRACT FROM AUTHOR]
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- 2024
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30. Global brain analysis of minor hallucinations in Parkinson's disease using EEG and MRI data.
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Chuan Liu, Liangcheng Qu, Qixue Li, Yiting Cao, Jingping Shi, Chao Yu, Weiguo Liu, and Kuiying Yin
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HALLUCINATIONS ,BRAIN ,FRONTAL lobe ,ELECTROENCEPHALOGRAPHY ,NEURAL pathways ,MAGNETIC resonance imaging ,MACHINE learning ,PARKINSON'S disease ,VISUAL perception ,SIGNAL processing ,RESEARCH funding ,DATA analysis ,ARTIFICIAL neural networks ,VISUAL evoked response ,MENTAL illness ,CEREBRAL cortex ,DISEASE complications - Abstract
Introduction: Visual hallucination is a prevalent psychiatric disorder characterized by the occurrence of false visual perceptions due to misinterpretation in the brain. Individuals with Parkinson's disease often experience both minor and complex visual hallucinations. The underlying mechanism of complex visual hallucinations in Parkinson's patients is commonly attributed to dysfunction in the visual pathway and attention network. However, there is limited research on the mechanism of minor hallucinations. Methods: To address this gap, we conducted an experiment involving 13 Parkinson's patients with minor hallucinations, 13 Parkinson's patients without hallucinations, and 13 healthy elderly individuals. We collected and analyzed EEG and MRI data. Furthermore, we utilized EEG data from abnormal brain regions to train a machine learning model to determine whether the abnormal EEG data were associated with minor hallucinations. Results: Our findings revealed that Parkinson's patients with minor hallucinations exhibited excessive activation of cortical excitability, an imbalanced interaction between the attention network and the default network, and disruption in the connection between these networks. These findings is similar to the mechanism observed in complex visual hallucinations. The visual reconstruction of one patient experiencing hallucinations yields results that differ from those observed in subjects without such symptoms. Discussion: The visual reconstruction results demonstrated significant differences between Parkinson's patients with hallucinations and healthy subjects. This suggests that visual reconstruction techniques may offer a means of evaluating hallucinations. [ABSTRACT FROM AUTHOR]
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- 2024
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31. Characteristics of ipsilateral, contralateral and bilateral masseter vestibular-evoked myogenic potential in healthy adults.
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Thirusangu, V P and Sinha, S K
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AUDITORY evoked response , *VESTIBULAR nerve , *HEARING , *STATISTICS , *MASSETER muscle , *IMPEDANCE audiometry , *COMPARATIVE studies , *SYMPTOMS , *DIAGNOSIS , *OTOACOUSTIC emissions , *DESCRIPTIVE statistics , *ACOUSTIC stimulation , *DATA analysis , *VISUAL evoked response , *EYE muscles - Abstract
Objective: This study aimed to characterise the ipsilateral, contralateral and bilateral masseter vestibular-evoked myogenic potential using clicks and 500 Hz tone burst stimuli in healthy adults. Method: Masseter vestibular-evoked myogenic potential was recorded from 20 healthy participants aged 19–28 years (11 males and 9 females). Masseter vestibular-evoked myogenic potential was recorded using 500 Hz tone burst and click stimuli in ipsilateral, contralateral and bilateral modes. Results: A statistically significant difference was observed between ipsilateral and contralateral stimulation for p11 latency, n21 latency and p11-n21 amplitude for both click and 500 Hz tone burst stimuli. The amplitude of the p11-n21 complex was higher for ipsilateral, contralateral and bilateral stimulations for 500 Hz tone burst than for click stimulus. Conclusion: This study showed a significant difference for p11-n21 amplitude between click and 500 Hz tone burst evoked masseter vestibular-evoked myogenic potential. In addition, bilateral stimulation elicited a larger response than ipsilateral and contralateral stimulation. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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32. A Perspective on Prosthetic Hands Control: From the Brain to the Hand.
- Author
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Gentile, Cosimo and Gruppioni, Emanuele
- Subjects
BRAIN physiology ,BRAIN anatomy ,ARTIFICIAL limbs ,GRIP strength ,NEUROSCIENCES ,ELECTROENCEPHALOGRAPHY ,EYE movements ,PROPRIOCEPTION ,NERVE conduction studies ,TOUCH ,NEURAL pathways ,AUDITORY perception ,PSYCHOLOGY of movement ,ARTIFICIAL intelligence ,BIOMEDICAL engineering ,ARM ,AMPUTEES ,LEARNING ,PHYSIOLOGICAL adaptation ,HAND ,VISION ,PROSTHESIS design & construction ,ELECTROMYOGRAPHY ,NEEDS assessment ,VISUAL evoked response - Abstract
The human hand is a complex and versatile organ that enables humans to interact with the environment, communicate, create, and use tools. The control of the hand by the brain is a crucial aspect of human cognition and behaviour, but also a challenging problem for both neuroscience and engineering. The aim of this study is to review the current state of the art in hand and grasp control from a neuroscientific perspective, focusing on the brain mechanisms that underlie sensory integration for hand control and the engineering implications for developing artificial hands that can mimic and interface with the human brain. The brain controls the hand by processing and integrating sensory information from vision, proprioception, and touch, using different neural pathways. The user's intention can be obtained to control the artificial hand by using different interfaces, such as electromyography, electroneurography, and electroencephalography. This and other sensory information can be exploited by different learning mechanisms that can help the user adapt to changes in sensory inputs or outputs, such as reinforcement learning, motor adaptation, and internal models. This work summarizes the main findings and challenges of each aspect of hand and grasp control research and highlights the gaps and limitations of the current approaches. In the last part, some open questions and future directions for hand and grasp control research are suggested by emphasizing the need for a neuroscientific approach that can bridge the gap between the brain and the hand. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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33. Neural Discrimination of Facial Cues Associated With Trustworthiness in Adults and 6-Month-Old Infants as Revealed by Fast Periodic Visual Stimulation.
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Baccolo, Elisa, Peykarjou, Stefanie, Quadrelli, Ermanno, Conte, Stefania, and Macchi Cassia, Viola
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ELECTRODES , *ELECTROENCEPHALOGRAPHY , *FACIAL expression , *ARTIFICIAL neural networks , *SOCIAL skills , *PERCEIVED discrimination , *PROMPTS (Psychology) , *TRUST , *TRUST in children , *VISUAL evoked response - Abstract
Adults and children easily distinguish between fine-grained variations in trustworthiness intensity based on facial appearance, but the developmental origins of this fundamental social skill are still debated. Using a fast periodic visual stimulation (FPVS) oddball paradigm coupled with electroencephalographic (EEG) recording, we investigated neural discrimination of morphed faces that adults perceive as low- and high-trustworthy in a sample of 6-month-old infants (N = 29; 56% male; Mage = 196.8 days; all White) and young adults (N = 21; 40% male; Mage = 24.61 years; all White) recruited in Italy. Stimulus sequences were presented at 6 Hz with deviant faces interleaved every fifth stimulus (i.e., 1.2 Hz); oddball category (high/low trustworthiness) was varied within subjects. FPVS responses were analyzed at both frequencies of interest and their harmonics as a function of deviant type (high- vs. low-trustworthy) over occipital and occipitolateral electrode clusters. For both infants and adults, the baseline response did not differ between trustworthiness conditions. Significant responses were centered on the right parietal electrodes in infants, and on the occipital and left occipitotemporal clusters in adults. Oddball responses were significant for both infants and adults, with cross-age differences in the topographical localization of the response on the scalp. Overall, results suggest that, by the age of 6 months, infants discriminate between faces that adults rate as high and low in trustworthiness, extending prior evidence of early sensitivity to this face dimension in humans. Public Significance Statement: The current study provides novel evidence that the human brain discriminates between faces that adults rate as high or low in trustworthiness, suggesting that sensitive responding to facial cues associated with trustworthiness is an early emerging and foundational feature of human social competences. Additionally, it demonstrates that the fast periodic visual stimulation paradigm is an effective tool for elucidating the ontogenetic roots of this sensitivity in early infancy. [ABSTRACT FROM AUTHOR]
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- 2023
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34. Evaluation of Fundus Function in Mature Cataract Patients by Visual Electrophysiology.
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Zhang, Min, Ji, Min, Tan, Mengjia, Yu, Ying, and Guan, Huaijin
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CATARACT , *PREOPERATIVE care , *VISUAL fields , *RETINA , *PHYSICIAN-patient relations , *CATARACT surgery , *TREATMENT effectiveness , *ELECTROPHYSIOLOGY , *T-test (Statistics) , *VISUAL acuity , *POSTOPERATIVE period , *DESCRIPTIVE statistics , *RESEARCH funding , *RECEIVER operating characteristic curves , *VISUAL evoked response , *ELECTRORETINOGRAPHY - Abstract
Purpose. To explore the value of visual electrophysiology in evaluating the fundus function of mature cataract patients. Methods. 124 mature cataract patients (153 eyes) were examined before cataract surgery; the examinations included best corrected visual acuity (BCVA), pattern visual evoked potential (PVEP), full-field electroretinogram (ffERG), and multifocal electroretinogram (mfERG). According to the postoperative fundus conditions, the subjects were divided into two groups: the no fundus disease group and the fundus disease group. Approximately one month after the operation, BCVA was measured, and visual electrophysiology was performed on subjects who had a stable fundus condition and had not received treatment for fundus disease. Results. One month after cataract surgery, BCVA ≤ 0.3 logMAR was found in 60 eyes (96.8%) without fundus disease and 59 eyes (64.8%) with fundus disease. Compared with the group without fundus disease, the preoperative electrophysiological examination of the group with fundus disease showed that the amplitude of ffERG waves and the amplitude density of the P1 wave in the 2nd to 5th rings of mfERG were decreased (all P < 0.05). ffERG and mfERG can be used for differential diagnosis of fundus disease (all P < 0.05), while PVEP has no significant diagnostic value for fundus disease (all P > 0.05). In the group without fundus disease, the amplitude of the PVEP 15′ P100 wave and the amplitude of dark-adapted (DA) 0.01 b-wave, DA 3.0 a-wave, and DA 10.0 a-wave were negatively correlated with postoperative logMAR BCVA (all P < 0.05). In the group with fundus disease, the amplitude of PVEP and ffERG and the amplitude density of mfERG were negatively correlated with postoperative logMAR BCVA (all P < 0.05). In the eyes of cortical cataracts, some parameters of PVEP, ffERG, and mfERG were significantly different before and after surgery. In the eyes of nuclear cataracts, some parameters of ffERG and mfERG were significantly different before and after surgery. In the eyes of posterior subcapsular cataracts, some parameters of PVEP and ffERG were significantly different before and after surgery. Conclusions. ffERG and mfERG can be used to detect fundus disease in mature cataract patients. The preoperative visual electrophysiological examination has high clinical value in predicting postoperative vision of mature cataract patients with fundus disease. Different types of cataracts have different effects on electrophysiological examination results. When interpreting the electrophysiological report, it is necessary to consider the existence of cataracts. This trial is registered with 2019-K068. [ABSTRACT FROM AUTHOR]
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- 2023
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35. Deprivation Amblyopia in the Setting of Bilateral Congenital Cataracts: A Case Report.
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Karim, Leyla
- Subjects
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CATARACT , *ULTRASONIC imaging , *DOWN syndrome , *AMBLYOPIA , *CATARACT surgery , *VISUAL acuity , *EARLY medical intervention , *VISUAL evoked response , *CHILDREN - Abstract
Background: A cataract is an opacity of the crystalline lens that has the potential to cause vison loss or visual distortion. Etiologies of congenital cataracts include genetic mutation, hereditary, intrauterine infection during pregnancy, persistent fetal vasculature, association with metabolic disorders, and chromosomal syndromes. Congenital cataracts can present unilaterally or bilaterally and in a myriad of shapes, sizes, and colors. Depending on these characteristics, congenital cataracts may or may not affect vision. If they do, these cataracts warrant prompt surgical intervention to prevent deprivation amblyopia, which is reduced visual acuity due to a disruption to normal visual development. Optometrists play a crucial role in making the correct diagnosis and prompt referral. In addition, optometrists are responsible for managing these patients postoperatively for amblyopia treatment, correction of residual ametropia, and various post-operative complications. Case Report: A four-year-old male with Down syndrome presented with bilateral dense cataracts, sensory nystagmus, and decreased visual acuity. Due to the cataracts, refractive error and retinal health were unable to be assessed clinically. The patient was referred for consultation for surgical management with a guarded prognosis. The patient was also referred for a visual evoked potential to determine visual potential. Conclusion: If visually significant, one of the greatest concerns of congenital cataracts is deprivation amblyopia. Following prompt surgical intervention, optometrists must manage these patients closely, often over the course of their lives, to ensure optimal visual development and ocular health. Even if a patient presents outside the ideal treatment window, it is still important to recommend treatment, as there can be significant visual improvement recorded post-surgery. [ABSTRACT FROM AUTHOR]
- Published
- 2023
36. Evaluation of Agreement Between Sweep Visual Evoked Potential Testing and Subjective Visual Acuity.
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Polat, Osman Ahmet, Şener, Hidayet, Çetinkaya, Zekeriya, and Arda, Hatice
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SKULL , *AGE distribution , *REGRESSION analysis , *SEX distribution , *VISION testing , *VISUAL acuity , *DESCRIPTIVE statistics , *VISUAL evoked response - Abstract
Objectives: The primary objective of this study was to evaluate the agreement of visual acuity (VA) obtained with the sweep visual evoked potential (sVEP) method with the VA obtained with the Snellen chart. The secondary objective was to examine the effect of age and gender on agreement. Materials and Methods: Best corrected VAs of subjects were recorded with the Snellen chart, and sVEP testing was performed according to the recommendations of the International Society for Clinical Electrophysiology of Vision (ISCEV). Snellen VAs and sVEP measurements were analyzed using logMAR conversion for statistical analysis. Agreement was evaluated with Bland-Altman analysis. Results: The study included 49 subjects with a mean age of 53.5±17.3 years (range: 19-75 years) and mean Snellen VA of 0.31±0.32 logMAR (range: 1.3-0.0 logMAR). In the Bland-Altman analysis, the mean differences between the VA and sVEP measurements (VA-sVEP) were significantly different and outside the limits of agreement (p=0.035). A significant proportional bias (p=0.0007) was found in the regression analysis performed between VA-sVEP and the mean VA. According to the Bland-Altman analysis of sex subgroups, there was a significant difference between VA and sVEP measurements in female subjects (p=0.006). The difference between VA and sVEP measurement increased significantly with older age (R2: 0.306, p<0.001, β: 0.05 [0.03, 0.08]). Conclusion: In conclusion, sVEP measurements and VAs did not show statistical agreement. Cranial anatomy and endocrine differences of the subjects may affect their sVEP measurements. The difference between the methods varies according to VA level. Directly using sVEP results instead of VA would not be appropriate. [ABSTRACT FROM AUTHOR]
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- 2023
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37. New insights into amiodarone induced retinal and optic nerve toxicity: functional and structural changes.
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Ebeid, Weam Mohamed, El-Shazly, Amany Abd El-Fattah, Kamal, Norhan Mohamed, Fakhary, Emad Effat, Mansour, Amr, and Ashour, Doaa Maamoun
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OPTIC nerve injuries ,RETINAL injuries ,RETINA physiology ,RETINAL anatomy ,SCIENTIFIC observation ,BLOOD vessels ,OPTIC nerve diseases ,ELECTROPHYSIOLOGY ,AMIODARONE ,OPTIC nerve ,OPTICAL coherence tomography ,RETINAL diseases ,ARRHYTHMIA ,COMPUTED tomography ,VISION disorders ,DRUG toxicity ,ELECTRORETINOGRAPHY ,VISUAL evoked response - Abstract
Background: Amiodarone is widely used for heart arrhytmia. Previous studies have suggested the possibility of optic neuropathy with the chronic use of this drug. Objectives: To identify structural or functional changes in the retina and optic nerve in patients on chronic amiodarone therapy without visual complaints. Methods: This observational study included 15 eyes of 15 patients with cardiac arrythmia on chronic amiodarone treatment and 15 healthy matched subjects as a control group. All subjects underwent electrophysiological tests [pattern visual evoked potential (PVEP), pattern electroretinogram (PERG), multifocal electroretinogram (mfERG), and optical coherence tomography (OCT) and angiography (OCTA)]. Results: There were no statistically significant differences between the two groups regarding the PVEP, PERG, and the mfERG parameters. Macular and optic nerve head OCT and OCTA have not shown statistically significant differences except for the morphological parameters of the optic disc (p = 0.008 for the horizontal and p = 0.013 for vertical cup/disc ratio and p = 0.045 for rim area). Conclusion: Patients on chronic amiodarone therapy have not shown evident structural or functional changes in the retinal or optic nerve as demonstrated by electrophysiological tests, OCT, and OCTA results compared to controls. [ABSTRACT FROM AUTHOR]
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- 2023
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38. A robust neural index of automatic generalization across variable natural views of familiar face identities.
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David, Justine, Koessler, Laurent, and Rossion, Bruno
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T-test (Statistics) , *DATA analysis , *RESEARCH funding , *VISUAL evoked response , *ELECTROENCEPHALOGRAPHY , *DESCRIPTIVE statistics , *ANALYSIS of variance , *STATISTICS , *VISUAL perception , *DATA analysis software , *FACE perception - Abstract
The ability to automatically and rapidly recognize a familiar face identity across different views is well documented but generally measured with explicit behavioural tasks involving many other processes. Here we provide a sensitive implicit neural measure of this ability using electroencephalographic (EEG) recordings coupled with fast periodic visual stimulation (FPVS). Images of two famous face identities alternated for 15 seconds at a frequency rate of 6 Hz, preceded by a 15 seconds adaptation period to images of one of the face identities. Beyond previous studies, numerous (N = 60) non-edited variable natural face images of each identity were presented, with different images appearing at adaptation (N = 30) and test. At the group-level (N = 16), 3 stimulation sequences only were sufficient to elicit highly significant EEG peaks at odd harmonics (3 and 9 Hz), reflecting face identity discrimination across variable novel views. This response was maximally localized over the right occipito-temporal region and statistically significant in 75% of individuals tested. Importantly, the face identity discrimination response at odd harmonics was significantly larger than when the exact same stimulation sequences were preceded by images of a face identity not present in the alternating sequence (irrelevant adaptation condition). Overall, this study provides a highly sensitive and objective technique to implicitly measure an individual's ability to generalize identity across different views of a familiar face identity. [ABSTRACT FROM AUTHOR]
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- 2023
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39. Exploring sensory sensitivity, cortical excitability, and habituation in episodic migraine, as a function of age and disease severity, using the pattern-reversal task.
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Marti-Marca, Angela, Vilà-Balló, Adrià, Cerda-Company, Xim, Ikumi, Nara, Torres-Ferrus, Marta, Caronna, Edoardo, Gallardo, Victor J., Alpuente, Alicia, Torralba Cuello, Mireia, Soto-Faraco, Salvador, and Pozo-Rosich, Patricia
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MIGRAINE diagnosis , *STATISTICS , *ELECTROENCEPHALOGRAPHY , *ANALYSIS of variance , *FISHER exact test , *MANN Whitney U Test , *REGRESSION analysis , *LEARNING , *SEVERITY of illness index , *T-test (Statistics) , *SENSORY defensiveness , *AGING , *VISUAL perception , *DESCRIPTIVE statistics , *RESEARCH funding , *DATA analysis software , *DATA analysis , *VISUAL evoked response - Abstract
Background: Migraine is a cyclic, neurosensory disorder characterized by recurrent headaches and altered sensory processing. The latter is manifested in hypersensitivity to visual stimuli, measured with questionnaires and sensory thresholds, as well as in abnormal cortical excitability and a lack of habituation, assessed with visual evoked potentials elicited by pattern-reversal stimulation. Here, the goal was to determine whether factors such as age and/or disease severity may exert a modulatory influence on sensory sensitivity, cortical excitability, and habituation. Methods: Two similar experiments were carried out, the first comparing 24 young, episodic migraine patients and 28 healthy age- and gender-matched controls and the second 36 middle-aged, episodic migraine patients and 30 healthy age- and gender-matched controls. A neurologist confirmed the diagnoses. Migraine phases were obtained using eDiaries. Sensory sensitivity was assessed with the Sensory Perception Quotient and group comparisons were carried out. We obtained pattern-reversal visual evoked potentials and calculated the N1-P1 Peak-to-Peak amplitude. Two linear mixed-effects models were fitted to these data. The first model had Block (first block, last block) and Group (patients, controls) as fixed factors, whereas the second model had Trial (all trials) and Group as fixed factors. Participant was included as a random factor in both. N1-P1 first block amplitude was used to assess cortical excitability and habituation was defined as a decrease of N1-P1 amplitude across Blocks/Trials. Both experiments were performed interictally. Results: The final samples consisted of 18 patients with episodic migraine and 27 headache-free controls (first experiment) and 19 patients and 29 controls (second experiment). In both experiments, patients reported increased visual hypersensitivity on the Sensory Perception Quotient as compared to controls. Regarding N1-P1 peak-to-peak data, there was no main effect of Group, indicating no differences in cortical excitability between groups. Finally, significant main effects of both Block and Trial were found indicating habituation in both groups, regardless of age and headache frequency. Conclusions: The results of this study yielded evidence for significant hypersensitivity in patients but no significant differences in either habituation or cortical excitability, as compared to headache-free controls. Although the alterations in patients may be less pronounced than originally anticipated they demonstrate the need for the definition and standardization of optimal methodological parameters. [ABSTRACT FROM AUTHOR]
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- 2023
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40. Shank3 deletion in PV neurons is associated with abnormal behaviors and neuronal functions that are rescued by increasing GABAergic signaling.
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Pagano, Jessica, Landi, Silvia, Stefanoni, Alessia, Nardi, Gabriele, Albanesi, Marica, Bauer, Helen F., Pracucci, Enrico, Schön, Michael, Ratto, Gian Michele, Boeckers, Tobias M., Sala, Carlo, and Verpelli, Chiara
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VISUAL evoked response , *PYRAMIDAL neurons , *VISUAL evoked potentials , *NEURONS , *SELF-injurious behavior , *AUTISM spectrum disorders - Abstract
Background: Phelan–McDermid syndrome (PMS) is a neurodevelopmental disorder characterized by developmental delay, intellectual disability, and autistic-like behaviors and is primarily caused by haploinsufficiency of SHANK3 gene. Currently, there is no specific treatment for PMS, highlighting the need for a better understanding of SHANK3 functions and the underlying pathophysiological mechanisms in the brain. We hypothesize that SHANK3 haploinsufficiency may lead to alterations in the inhibitory system, which could be linked to the excitatory/inhibitory imbalance observed in models of autism spectrum disorder (ASD). Investigation of these neuropathological features may shed light on the pathogenesis of PMS and potential therapeutic interventions. Methods: We recorded local field potentials and visual evoked responses in the visual cortex of Shank3∆11−/− mice. Then, to understand the impact of Shank3 in inhibitory neurons, we generated Pv-cre+/−Shank3Fl/Wt conditional mice, in which Shank3 was deleted in parvalbumin-positive neurons. We characterized the phenotype of this murine model and we compared this phenotype before and after ganaxolone administration. Results: We found, in the primary visual cortex, an alteration of the gain control of Shank3 KO compared with Wt mice, indicating a deficit of inhibition on pyramidal neurons. This alteration was rescued after the potentiation of GABAA receptor activity by Midazolam. Behavioral analysis showed an impairment in grooming, memory, and motor coordination of Pv-cre+/−Shank3Fl/Wt compared with Pv-cre+/−Shank3Wt/Wt mice. These deficits were rescued with ganaxolone, a positive modulator of GABAA receptors. Furthermore, we demonstrated that treatment with ganaxolone also ameliorated evocative memory deficits and repetitive behavior of Shank3 KO mice. Limitations: Despite the significant findings of our study, some limitations remain. Firstly, the neurobiological mechanisms underlying the link between Shank3 deletion in PV neurons and behavioral alterations need further investigation. Additionally, the impact of Shank3 on other classes of inhibitory neurons requires further exploration. Finally, the pharmacological activity of ganaxolone needs further characterization to improve our understanding of its potential therapeutic effects. Conclusions: Our study provides evidence that Shank3 deletion leads to an alteration in inhibitory feedback on cortical pyramidal neurons, resulting in cortical hyperexcitability and ASD-like behavioral problems. Specifically, cell type-specific deletion of Shank3 in PV neurons was associated with these behavioral deficits. Our findings suggest that ganaxolone may be a potential pharmacological approach for treating PMS, as it was able to rescue the behavioral deficits in Shank3 KO mice. Overall, our study highlights the importance of investigating the role of inhibitory neurons and potential therapeutic interventions in neurodevelopmental disorders such as PMS. [ABSTRACT FROM AUTHOR]
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- 2023
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41. Höffding step and beyond: The impact of visual sensory impairment on cognitive performance in neuropsychological testing of survivors of acute methanol poisoning.
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Bukacova, Katerina, Mana, Josef, Zakharov, Sergey, Diblík, Pavel, Pelclova, Daniela, Urban, Pavel, Klepiš, Petr, Klempíř, Jiří, Libon, David J., Růžička, Evžen, and Bezdicek, Ondrej
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METHANOL , *SENSORY disorders , *DIFFERENTIAL diagnosis , *NEUROPSYCHOLOGICAL tests , *OPTIC nerve , *OPTICAL coherence tomography , *RESEARCH funding , *DESCRIPTIVE statistics , *VISION disorders , *COGNITIVE testing , *VISUAL evoked response - Abstract
BACKGROUND: Sensory deficits can result in limitations regarding how well neuropsychological test findings can be interpreted. Only a few studies have investigated the influence of vision alteration on neuropsychological tests. In 2012 the Czech Republic experienced mass methanol poisoning. Methanol metabolites cause histotoxic hypoxia to the optic nerve. OBJECTIVE: In the current study, the effect of the toxic damage on the parts of the visual pathway on visual and non-visual neuropsychological measures was investigated using electrophysiological methods (visual evoked potential (VEP) and optical coherence tomography (OCT) with retinal nerve fibre layer (RNFL) thickness measurement. METHODS: 53 individuals who experienced methanol poisoning participated in this research (76% men; ages 24 to 74 years, mean = 43.8±14.6 years; education 11.9±1.4 years). Each participant underwent comprehensive neurological, ophthalmological, and neuropsychological examinations. RESULTS: The results of mixed-effect models revealed significant small to a medium association between the Stroop test weak interference and Grooved Pegboard with the left eye global, nasal and temporal RNFL thickness. Also, medium associations between the Finger Tapping test and the Stroop test weak interference and left eye temporal RNFL, right eye temporal RNFL, and the latency P1 of VEP in the left eye were significant. CONCLUSION: The results of this study found a small to medium association (r =.15–.33; p =.010–.046) between RNFL thickness and cognitive visual test performance. Careful interpretation is suggested regarding results obtained from visual tests of the executive or motor functioning with participants with RNFL decrease or other types of early visual processing damage. [ABSTRACT FROM AUTHOR]
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- 2023
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42. Intraoperative Neuromonitoring of the Visual Pathway in Asleep Neuro-Oncology Surgery.
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Soumpasis, Christos, Díaz-Baamonde, Alba, Ghimire, Prajwal, Baig Mirza, Asfand, Borri, Marco, Jarosz, Josef, Gullan, Richard, Ashkan, Keyoumars, Bhangoo, Ranjeev, Vergani, Francesco, Lavrador, Jose Pedro, and Mirallave Pescador, Ana
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RESEARCH , *NEURAL pathways , *NEUROSURGERY , *TREATMENT effectiveness , *BRAIN tumors , *INTRAOPERATIVE monitoring , *ONCOLOGIC surgery , *VISION disorders , *STATISTICAL correlation , *VISUAL evoked response , *LONGITUDINAL method - Abstract
Simple Summary: To optimise patient outcomes in tumour surgery in visual eloquent areas, it is crucial to preserve the integrity of the visual pathways. The aim of our prospective study is to examine the use of visual evoked potentials (VEPs), utilising different techniques such as transcranial and direct cortical recording. In a cohort of 39 patients, we established a significant correlation between the infiltration of the optic radiation by the tumour on tractography and the occurrence of visual field deficits after surgery. In contrast to the transcranial recordings, direct cortical VEP recordings exhibited a robust correlation with visual outcomes. Lastly, a 40% decrease in the amplitude of the N75 and P100 waves of the direct cortical recordings was associated with the risk of a worsening visual outcome. VEP monitoring can be a reliable method to detect visual deficits, but there is a need to improve the technique as it is prone to false warnings. Brain tumour surgery in visual eloquent areas poses significant challenges to neurosurgeons and has reported inconsistent results. This is a single-centre prospective cohort study of patients admitted for asleep surgery of intra-axial lesions in visual eloquent areas. Demographic and clinical information, data from tractography and visual evoked potentials (VEPs) monitoring were recorded and correlated with visual outcomes. Thirty-nine patients were included (20 females, 19 males; mean age 52.51 ± 14.08 years). Diffuse intrinsic glioma was noted in 61.54% of patients. There was even distribution between the temporal, occipital and parietal lobes, while 55.26% were right hemispheric lesions. Postoperatively, 74.4% remained stable in terms of visual function, 23.1% deteriorated and 2.6% improved. The tumour infiltration of the optic radiation on tractography was significantly related to the visual field deficit after surgery (p = 0.016). Higher N75 (p = 0.036) and P100 (p = 0.023) amplitudes at closure on direct cortical VEP recordings were associated with no new postoperative visual deficit. A threshold of 40% deterioration of the N75 (p = 0.035) and P100 (p = 0.020) amplitudes correlated with a risk of visual field deterioration. To conclude, direct cortical VEP recordings demonstrated a strong correlation with visual outcomes, contrary to transcranial recordings. Invasion of the optic radiation is related to worse visual field outcomes. [ABSTRACT FROM AUTHOR]
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- 2023
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43. Galcanezumab treatment changes visual related EEG connectivity patterns in migraine patients.
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La Rocca, Marianna, Laporta, Anna, Clemente, Livio, Ammendola, Elena, Delussi, Marianna Diletta, Ricci, Katia, Tancredi, Giusy, Stramaglia, Sebastiano, and de Tommaso, Marina
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MIGRAINE , *ELECTROENCEPHALOGRAPHY , *FALSE discovery rate , *VISUAL evoked response , *MONOCLONAL antibodies , *EPILEPSY - Abstract
Background: Monoclonal antibodies against calcitonin gene-related peptides (CGRP) are innovative therapies for migraine treatment. Although they are clinically effective, how anti-CGRP treatment reduces migraine attacks still remains unclear. Objective: In this observational case–control study, we aimed to apply graph theory to EEG data from 20 migraine patients and 10 controls to investigate the effects of 3 months of galcanezumab on brain connectivity. Methods: We analyzed EEG rhythms during black-white pattern reversal stimulation with 0.5 cycle per degree spatial frequency before (T0) galcanezumab injection, as well as after 3 months (T2). EEG recordings made 1 hour after galcanezumab administration served as the control session (T1). Patients' connectivity patterns obtained at T0, T1 and T2 were compared with normal controls. Results: We found that galcanezumab increased network integration (with a 5% significance level corrected with the false discovery rate), changing the intensity of connections between the occipital through the frontal areas. At 3 months follow up, patients with persistent high headache intensity had a minor effect on the strength of connections (evaluated using Kendall's rank correlation test and p < 0.05). Conclusions: The potent anti-nociceptive action that galcanezumab exerts at a peripheral level could restore cortical connections and possibly factors predisposing to attack onset. [ABSTRACT FROM AUTHOR]
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- 2023
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44. Aging effect of cross-modal interactions during audiovisual detection and discrimination by behavior and ERPs.
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Yanna Ren, Yan Li, Zhihan Xu, Rui Luo, Runqi Qian, Jieping Duan, Jiajia Yang, and Weiping Yang
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PSYCHOLOGICAL aspects of aging ,AUDITORY evoked response ,STATISTICS ,ELECTROENCEPHALOGRAPHY ,ANALYSIS of variance ,AUDITORY perception ,AGE distribution ,PSYCHOLOGICAL tests ,T-test (Statistics) ,VISUAL perception ,HEALTH behavior ,RESEARCH funding ,DESCRIPTIVE statistics ,DATA analysis software ,DATA analysis ,VISUAL evoked response - Abstract
Introduction: Numerous studies have shown that aging greatly affects audiovisual integration; however, it is still unclear when the aging effect occurs, and its neural mechanism has yet to be fully elucidated. Methods: We assessed the audiovisual integration (AVI) of older (n = 40) and younger (n = 45) adults using simple meaningless stimulus detection and discrimination tasks. The results showed that the response was significantly faster and more accurate for younger adults than for older adults in both the detection and discrimination tasks. The AVI was comparable for older and younger adults during stimulus detection (9.37% vs. 9.43%); however, the AVI was lower for older than for younger adults during stimulus discrimination (9.48% vs. 13.08%) behaviorally. The electroencephalography (EEG) analysis showed that comparable AVI amplitude was found at 220-240 ms for both groups during stimulus detection and discrimination, but there was no significant difference between brain regions for older adults but a higher AVI amplitude in the right posterior for younger adults. Additionally, a significant AVI was found for younger adults in 290-310 ms but was absent for older adults during stimulus discrimination. Furthermore, significant AVI was found in the left anterior and right anterior at 290-310 ms for older adults but in the central, right posterior and left posterior for younger adults. Discussion: These results suggested that the aging effect of AVI occurred in multiple stages, but the attenuated AVI mainly occurred in the later discriminating stage attributed to attention deficit. [ABSTRACT FROM AUTHOR]
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- 2023
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45. Visual Evoked Potentials as an Early-Stage Biomarker in the rTg4510 Tauopathy Mouse Model.
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Parka, Aleksandra, Volbracht, Christiane, Hall, Benjamin, Bastlund, Jesper F., Nedergaard, Maiken, Laursen, Bettina, Botta, Paolo, and Sotty, Florence
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VISUAL evoked potentials , *TAUOPATHIES , *VISUAL evoked response , *LABORATORY mice , *ALZHEIMER'S disease - Abstract
Background: Tauopathies such as Alzheimer's disease (AD) and frontotemporal dementia (FTD) are characterized by formation of neurofibrillary tangles consisting of hyperphosphorylated tau protein. Early pathophysiological and functional changes related to neurofibrillary tangles formation are considered to occur prior to extensive neurodegeneration. Hyperphosphorylated tau has been detected in postmortem retinas of AD and FTD patients, and the visual pathway is an easily accessible system in a clinical setting. Hence, assessment of the visual function may offer the potential to detect consequences of early tau pathology in patients. Objective: The aim of this study was to evaluate visual function in a tauopathy mouse model in relation to tau hyperphosphorylation and neurodegeneration. Methods: In this study we explored the association between the visual system and functional consequences of tau pathology progression using a tauopathy rTg4510 mouse model. To this end, we recorded full-field electroretinography and visual evoked potentials in anesthetized and awake states at different ages. Results: While retinal function remained mostly intact within all the age groups investigated, we detected significant changes in amplitudes of visual evoked potential responses in young rTg4510 mice exhibiting early tau pathology prior to neurodegeneration. These functional alterations in the visual cortex were positively correlated with pathological tau levels. Conclusion: Our findings suggest that visual processing could be useful as a novel electrophysiological biomarker for early stages of tauopathy. [ABSTRACT FROM AUTHOR]
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- 2023
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46. Effects of Smoking on Pattern Visual Evoked Potentials.
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Eski, Mehmet Tahir, Yabalak, Ahmet, Sahan, Halime, Ayasli, Alper Aziz Hudai, and Sezer, Taha
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STATISTICS ,NEUROLOGY ,CLINICS ,MANN Whitney U Test ,COMPARATIVE studies ,T-test (Statistics) ,PEARSON correlation (Statistics) ,CHI-squared test ,SMOKING ,OPHTHALMOLOGY ,DATA analysis software ,DATA analysis ,VISUAL evoked response - Abstract
Aim: The aim of the study is to get a better understanding of the side effects of smoking by evaluating the effect of recently elevated smoking rate on Visual Evoked Potentials (VEP) and to determine whether it is necessary to use different normals when evaluating the VEP measurements of smoking patients. Material and Methods: The patients who have applied to our ophthalmology and neurology outpatient clinics during 2021-2022 are included to the study. Detailed ophthalmologic examination of the patients as well as their VEP test is completed followed by a dilated fundus examination assessment. The patients with normal results are included to the study. The smoking rate is calculated on pack/year basis. Pattern VEP (PVEP) recording is performed based on Keypoint (Dantec, Denmark) and International Society for Clinical Electrophysiology of Vision (ISCEV) criteria. Data obtained through the study are analyzed by SPSS 21.0 version software. Countable variables with normal distribution between two independent groups are analyzed with Independent Sample T test whereas variables without normal distribution are analyzed with Mann Whitney U test. Chi-square test is used for comparing categorical variables. Results: 71 patients were included to the study where 33 of them were placed in smoking group and 38 in non-smoking group (control group). Smoking group had a yearly cigarette package consumption of 5.20±8.93 (0.2-40). VEP latency and amplitude changes were compared and according to the obtained results; there was P100 latency prolongation in between left and right eye of the patients in the control group and smoking group but it did not have any statistical significance (p=0.910 and p=0.697 respectively). There was no statistically significant difference in either left nor right eye in terms of smoking and P100 and N70 latencies (p=0.707, p=0.838, p=0.717 and p=0.621 respectively). Similarly, there was no significant correlation between yearly package consumption and P100 and N70 latencies and amplitudes of left and right eyes (p=0.503, p=0.410, p=0.776 and p=0.940 respectively). Conclusion: No significant effect of smoking is found on VEP values thus leading us to believe that the same normal intervals can be used in the evaluation of VEP results of both smoking and non-smoking patients. [ABSTRACT FROM AUTHOR]
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- 2023
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47. VISUAL EVOKED RESPONSES IN ADOLESCENT IDIOPATHIC SCOLIOSIS.
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Inanc, Gonca, Akcay, Burcin, Ozgoren, Murat, Simsek, Ibrahim Engin, and Oniz, Adile
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VISUAL evoked response ,ADOLESCENT idiopathic scoliosis ,VISUAL evoked potentials ,VISUAL perception ,VIDEO recording - Abstract
Purpose: In electrophysiological studies conducted with adolescent idiopathic scoliosis (AIS) patients, no prior studies examining the visual evoked potentials of AIS patients were found in conjunction with objective vertical perception. The aim of this study was to examine the visual evoked potentials of individuals with AIS and healthy individuals in terms of their brain responses. Material and Methods: Twelve AIS patients (12.75±0.86 years) and 10 healthy subjects (13.80±1.68 years) participated. A 64-channel electroencephalography (EEG) recording system, Embedded Microcontroller Unit (EMISU), visual stimulation unit, EEG cap, and video recording system were used to examine brain responses after applying visual stimulus. Results: In AIS and control groups (CG), three positive and two negative peaks were observed after applying the stimulus. In the AIS, the first and second negative, and second positive peaks, and in the CG, the second positive and negative peaks appeared significantly earlier in the frontal region. The amplitude of the third positive peak in all regions was found to be higher in the AIS. In AIS and CG, the second positive peak was found to be significantly higher in the parieto-occipital region. Conclusion: It can be judged that AIS patients use more sources for processing the vertical visual stimuli than procedures compared to healthy individuals. In light of the findings obtained, the effect of treatments applied to AIS patients with the method used in this study can be evaluated in terms of brain responsiveness. In addition to the subjective visual perception of individuals with AIS, this method can also evaluate objective vertical perception. [ABSTRACT FROM AUTHOR]
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- 2023
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48. Application of supervised machine learning algorithms for the evaluation of utricular function on patients with Meniere's disease: utilizing subjective visual vertical and ocular-vestibular-evoked myogenic potentials.
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Bragg, Phillip G., Norton, Benjamin M., Petrak, Michelle R., Weiss, Allyson D., Kandl, Lindsay M., Corrigan, Megan L., Bahner, Cammy L., and Matsuoka, Akihiro J.
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VESTIBULAR apparatus physiology , *AUDITORY evoked response , *EVOKED potentials (Electrophysiology) , *MACHINE learning , *MENIERE'S disease , *RESEARCH funding , *LOGISTIC regression analysis , *VISUAL evoked response , *ALGORITHMS , *LONGITUDINAL method , *PROBABILITY theory , *NEUROLOGIC examination - Abstract
Research on the otolith organs remains inconclusive. This study seeks to further elucidate utricular function in patients with Meniere's disease (MD) in three ways: (1) We aimed to disambiguate the role of the Subjective Visual Vertical (SVV) and Ocular Vestibular Evoked Myogenic Potential (o-VEMP) tests regarding which utricular subsystem each is measuring. (2) We sought to characterize the acute and chronic state of MD by identifying differences in the relationship of SVV and o-VEMP results across patients with acute and chronic MD. (3) We attempted to find a machine-learning algorithm that could predict acute versus chronic MD using SVV and o-VEMP. A prospective study with ninety subjects. (1) SVV and o-VEMP tests were found to have a moderate linear relationship in patients with acute MD, suggesting each test measures a different utricular subsystem. (2) Regression analyses statistically differed across the two patient populations, suggesting that SVV results were normalized in chronic MD patients. (3) Logistic regression and Naïve Bayes algorithms were found to predict acute and chronic MD accurately. A better understanding of what diagnostic tests measure will lead to a better classification system for MD and more targeted treatment options in the future. [ABSTRACT FROM AUTHOR]
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- 2023
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49. Effects of Background Music on Mental Fatigue in Steady-State Visually Evoked Potential-Based BCIs.
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Gao, Shouwei, Zhou, Kang, Zhang, Jun, Cheng, Yi, and Mao, Shujun
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EXPERIMENTAL design ,STATISTICS ,ELECTROENCEPHALOGRAPHY ,ANALYSIS of variance ,BRAIN-computer interfaces ,SELF-evaluation ,RESEARCH funding ,DESCRIPTIVE statistics ,MUSIC ,DATA analysis software ,DATA analysis ,MENTAL fatigue ,VISUAL evoked response - Abstract
As a widely used brain–computer interface (BCI) paradigm, steady-state visually evoked potential (SSVEP)-based BCIs have the advantages of high information transfer rates, high tolerance for artifacts, and robust performance across diverse users. However, the incidence of mental fatigue from prolonged, repetitive stimulation is a critical issue for SSVEP-based BCIs. Music is often used as a convenient, non-invasive means of relieving mental fatigue. This study investigates the compensatory effect of music on mental fatigue through the introduction of different modes of background music in long-duration, SSVEP-BCI tasks. Changes in electroencephalography power index, SSVEP amplitude, and signal-to-noise ratio were used to assess participants' mental fatigue. The study's results show that the introduction of exciting background music to the SSVEP-BCI task was effective in relieving participants' mental fatigue. In addition, for continuous SSVEP-BCI tasks, a combination of musical modes that used soothing background music during the rest interval phase proved more effective in reducing users' mental fatigue. This suggests that background music can provide a practical solution for long-duration SSVEP-based BCI implementation. [ABSTRACT FROM AUTHOR]
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- 2023
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50. A Cause of Refractory Seizures: Fumarase Deficiency.
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Yekedüz, Merve Koç, Doğulu, Neslihan, Öncül, Ümmühan, Köse, Engin, Ünal, Özlem, and Eminoğlu, Fatma Tuba
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INBORN errors of metabolism diagnosis ,HYDROLASES ,PHYSICAL diagnosis ,LISSENCEPHALY ,CEREBRAL cortex abnormalities ,HYDROCEPHALUS ,NEURAL development ,COMPUTED tomography ,ELECTROENCEPHALOGRAPHY ,VISUAL evoked response ,ASPIRATION pneumonia ,RESPIRATORY insufficiency ,MAGNETIC resonance imaging ,TREATMENT effectiveness ,MUSCLE hypotonia ,ATRIAL septal defects ,SEIZURES (Medicine) ,DISEASE complications ,ECHOCARDIOGRAPHY ,GENETIC testing - Abstract
Abstract: Fumarase is an enzyme involved in the Krebs cycle. Fumarase deficiency (FD) is an autosomal recessive disorder that is associated with neurocognitive dysfunctions. In the absence of fumarase, fumarate is accumulated and excreted in the urine. FD has been reported with polyhydramnios, intrauterine growth retardation, prematurity, hypotonia, seizure, facial anomalies, malnutrition, relative macrocephaly, and developmental retardation. Cranial imaging findings are enlargement of the ventricles, polymicrogyria, and thinning of the corpus callosum. Electroencephalogram findings are generally compatible with hypsarrhythmia. Treatment is generally supportive. Although protein-restricted diets have been tried, their benefits have not been proven. This report aimed to present a case with hypotonia, and refractory seizures were diagnosed at a very early age, and a summary of the cases is found in the literature. [ABSTRACT FROM AUTHOR]
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- 2023
- Full Text
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