128 results on '"BRAIN ACTIVITY"'
Search Results
2. Creating A dynamic cognovisor – Brain activity recognition using principal Component analysis and Machine learning models
- Author
-
Gadzhiev, Ismail M., Makarov, Alexander S., Ushakov, Vadim L., Orlov, Vyacheslav A., Ivanitsky, Georgy A., and Dolenko, Sergei A.
- Published
- 2025
- Full Text
- View/download PDF
3. Clinical efficacy of NIBS in enhancing neuroplasticity for stroke recovery
- Author
-
Ye, Qing, Wang, Xin, Li, Ting, Xu, Jing, and Ye, Xiangming
- Published
- 2025
- Full Text
- View/download PDF
4. Modulation of anticipatory brain activity as a function of action complexity
- Author
-
Casella, Andrea, Di Bello, BiancaMaria, Aydin, Merve, Lucia, Stefania, Russo, Francesco Di, and Pitzalis, Sabrina
- Published
- 2024
- Full Text
- View/download PDF
5. Effects of anodal transcranial direct current stimulation over motor cortex on resting-state brain activity in the early subacute stroke phase: A power spectral density analysis
- Author
-
Bernardes, Tiago Soares, Santos, Kelly Cristina Sousa, Nascimento, Monalisa Resende, Filho, César Augusto Noronha e Sousa, Bazan, Rodrigo, Pereira, Janser Moura, de Souza, Luciane Aparecida Pascucci Sande, and Luvizutto, Gustavo José
- Published
- 2024
- Full Text
- View/download PDF
6. PSGpower: A MATLAB toolbox for analyzing sleep EEG data
- Author
-
Fitzroy, Ahren B. and Spencer, Rebecca M.C.
- Published
- 2025
- Full Text
- View/download PDF
7. Assessment of the effect of attentional control and experience on event-related potential P300 in visual perception during vehicle driving.
- Author
-
Yamamoto, Kota, Wagatsuma, Nobuhiko, Nobukawa, Sou, and Inagaki, Keiichiro
- Subjects
- *
ATTENTION control , *EVOKED potentials (Electrophysiology) , *MOTOR vehicle driving , *PERCEIVED control (Psychology) , *VISUAL perception , *TRAFFIC safety , *DISTRACTION - Abstract
• The effects of driving experience and attentional control on the perception of driving scenes were experimentally investigated through the event-related potential P300. • Both driving experience and attentional control elevated the performance of target perception. • Greater improvement in the latency of the P300 and reaction time for the perceptual target was observed in the driving experience than attentional control. • The greater contribution of experience in aiding the performance of visual attention in scene perception rather than attentional control. Numerous types of objects in traffic scenes are visually perceived and recognized to determine safe driving maneuvers. Visual attention is the most important brain function for selecting and processing necessary information in the driving environment. To perceive various targets during driving, attentional resources are distributed across the entire scene. Direct control of attention through instruction and/or cues, which result in tuning the resolution of attentional areas, aids the performance of attention. Additionally, the fixation point distribution of an experienced driver becomes wider and tends to shift to the location where the vehicle will be in the next few seconds. Electroencephalography studies have shown distinct characteristics in the attention-related event-related potential known as P300 between experienced and beginner drivers. These findings suggest that experience allows for the optimization of visual attention and direct attentional control. However, it remains unknown how they differ in altering visual attention performance and related brain activity. This study experimentally investigated the effects of driving experience and attentional control on the perception of driving scenes using the event-related potential P300. Our results showed a greater improvement in P300 latency for perceptual targets with driving experience rather than an increase in visual attention intensity. The results suggest that experience enhances visual attention more effectively than attentional control in terms of acceleration of brain signal processing. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
8. Advancements in non-invasive microwave brain stimulation: A comprehensive survey.
- Author
-
Pereira, Francisco Estevão Simão, Jagatheesaperumal, Senthil Kumar, Benjamin, Stephen Rathinaraj, Filho, Paulo Cezar do Nascimento, Duarte, Florence Tupinambá, and de Albuquerque, Victor Hugo C.
- Abstract
• The survey focuses on non-invasive brain stimulation techniques, highlighting their significance in offering novel perspectives for comprehending and treating neurological disorders. • Focuses on the dynamic landscape of deep brain stimulation, with a special emphasis on the evolving role of microwave technology. • Explores how advancements in antenna structures and optimization strategies are shaping the future of high-frequency microwave stimulation, indicating a transformative journey within the field. • Provides a safer and more precise means of modulating neural activity, potentially leading to more effective and targeted interventions. This survey provides a comprehensive insight into the world of non-invasive brain stimulation and focuses on the evolving landscape of deep brain stimulation through microwave research. Non-invasive brain stimulation techniques provide new prospects for comprehending and treating neurological disorders. We investigate the methods shaping the future of deep brain stimulation, emphasizing the role of microwave technology in this transformative journey. Specifically, we explore antenna structures and optimization strategies to enhance the efficiency of high-frequency microwave stimulation. These advancements can potentially revolutionize the field by providing a safer and more precise means of modulating neural activity. Furthermore, we address the challenges that researchers currently face in the realm of microwave brain stimulation. From safety concerns to methodological intricacies, this survey outlines the barriers that must be overcome to fully unlock the potential of this technology. This survey serves as a roadmap for advancing research in microwave brain stimulation, pointing out potential directions and innovations that promise to reshape the field. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
9. Exploratory' study on driving ability of people with schizophrenia: Relationships among cognitive function, symptoms, and brain activity.
- Author
-
Okada, Hiroki, Morimoto, Takafumi, and Ikeda, Nozomu
- Subjects
- *
PEOPLE with schizophrenia , *COGNITIVE ability , *COGNITIVE processing speed , *MOTOR vehicle driving , *TRAIL Making Test , *VISUAL memory - Abstract
This study aimed to examine the relationships among cognitive function, symptoms, prefrontal activation, basic driving skills, and collision risk factors using a hazard prediction task in simulated driving. Participants included 42 people with schizophrenia aged 20–50 years who had actual experience of driving. The Trail making test (TMT) A and TMT B, Wechsler Memory Test–Revised (WMS-R), and Zoo Map test (ZMT) were used to evaluate cognitive function. Positive and negative syndrome scale was used to assess symptoms, and brain activity was assessed by evaluating cerebral blood flow during a visual working memory task using functional near-infrared spectroscopy. Driving tasks that tested basic skills, such as brake reaction, steering wheel skills, and standard deviation of lateral position, were analyzed using multiple regression analysis. Three hazard prediction tasks were performed using discriminant analysis. Brake reaction associated with cerebral blood flow and TMT-A. Steering wheel skills associated with WMS-R, driving experience and depression. Significant differences were found between the collision and noncollision groups in the hazard prediction task, as shown by the ZMT, driving experience, and brake reaction. Brain activity in the frontal lobe during a desk task may be useful data for driving assessment. Assessment of processing speed and learning ability may be particularly important in the evaluation of basic skills for safe driving. In addition, for people with schizophrenia, foresight, as represented by proactive planning, experience, and quick braking may be an essential characteristic to anticipate danger and react quickly enough to avoid collisions. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
10. Improved LSTM-Squeeze Net Architecture for brain activity detection using EEG with improved feature set.
- Author
-
Mastan Sharif, S.K., Butta, Rajasekhar, Venkata Rao, Dhulipalla, Murthy, G.L.N., and Manikanda Devarajan, N.
- Subjects
FEATURE extraction ,SIGNAL filtering ,LEAST squares ,ELECTROENCEPHALOGRAPHY ,SIGNALS & signaling - Abstract
• We introduce a new BAR model using EEG signal. • Initially, EEG filtering is done using adaptive least mean square-based filtering. • Then, WPD, time domain, morphological and improved CSP features are extracted. • Further, appropriate features are selected with Improved Mutual Information (IMI). • Detection of brain actions is done via improved LSTM and Squeeze net. • The ILSTM and Squeezenet results are averaged and brain activity is recognized. Brain activity recognition (BAR) has emerged as most intriguing fields of research in recent days. It poses the ability to transform an extensive number of appliances, together with ICU surveillance, appliance control for the disabled and aged, and the detection of neural diseases. EEG data are the most common representation of brain activity, as they capture the voltage variations of neurons in the brain using non-invasive electrodes implanted on the scalp. Deep learning models play a major role in recognizing brain activity. This work uses EEG inputs to present a new hybrid model-based BAR. Adaptive least mean square (ALMS) is first used to filter the input signal for EEG signals. Next, improved CSP features, morphological features, temporal domain features, and wavelet packet decomposition (WPD) features are extracted. Appropriate characteristics are chosen following feature extraction using Improved Mutual Information (IMI). Then, using an enhanced LSTM (ILSTM)-Squeeze net model, brain actions are detected or recognized. The highest accuracy at LP = 90 is around 0.961. In contrast, the precisions of 0.7385, 0.667, 0.7516, 0.771, 0.686, 0.7124, and 0.7189 were obtained by Dense Net, Mobile Net, Squeeze Net, Res Net, ANN, LSTM, and RNN. The evaluation done proves the efficiency of the proposed model over the other conventional models. [ABSTRACT FROM AUTHOR]
- Published
- 2025
- Full Text
- View/download PDF
11. Assessment of brain function during stunning and killing of channel catfish (Ictalurus punctatus).
- Author
-
Hjelmstedt, Per, To, Filip, Allen, Peter J., and Gräns, Albin
- Subjects
- *
VISUAL evoked response , *CHANNEL catfish , *LOSS of consciousness , *ELECTRIC shock , *DOMESTIC animals - Abstract
Measurement of brain activity is a reliable method to determine loss of consciousness during the slaughter of terrestrial farm animals. In fish, the ability to obtain an electroencephalogram (EEG), even in unrestrained individuals, has enabled the assessment and optimization of stunning and killing methods in aquaculture. This study evaluated the effect of percussive and in-water electrical stunning in channel catfish (Ictalurus punctatus) using the loss of visual evoked responses (VERs) as indicator of loss of consciousness. Our results show that percussive stunning with a fish bonker effectively caused permanent disruption of normal brain function when applied correctly. However, there is a risk of mis-stuns, with 20 % of the catfish showing temporarily or permanently responsiveness after stunning (i.e. presence of VERs). Exposure to an electric field strength of 13 V rms cm−1 and a current density of 1.3 A rms dm−2 for 1 s caused immediate but, in contrast to successful percussive stunning, transient loss of VERs. Extending the exposure time to 10 s using the same electrical parameters did not affect recovery based on VERs, nor did increasing the field strength to 24 V rms cm−1 and a current density to 2.1 A rms dm−2 using a 10 s exposure time. The recovery time was also unaffected by post-stun placement of fish in air or water. However, a 10 s shock with an electric field of 24 V rms cm−1 and a current density of 2.1 A rms dm−2 immediately followed by decapitation, prevented recovery in 70 % of the catfish with the remaining 30 % experiencing temporary recovery (i.e. presence of VERs) for a few minutes. Our findings show that different stunning methods offer distinct advantages and limitations. Modifying the slaughter protocol in commercial catfish production, considering these methods, could significantly enhance the welfare of channel catfish during slaughter. • In-water electrical stunning can induce loss of consciousness in channel catfish. • Investigated field strengths and current densities had no effect on recovery time. • Recovery in air or water have no effect on time to recovery. • Electric stunning followed by decapitation prevented recovery in 70 % of the fish. • Percussive stunning can induce permanent loss of consciousness if done correctly. [ABSTRACT FROM AUTHOR]
- Published
- 2025
- Full Text
- View/download PDF
12. Effects of electrical and percussive stunning on neural, ventilatory and cardiac responses of rainbow trout.
- Author
-
Brijs, Jeroen, Hjelmstedt, Per, Sundell, Erika, Berg, Charlotte, Sandblom, Erik, and Gräns, Albin
- Subjects
- *
LOSS of consciousness , *CENTRAL nervous system , *SYSTEM failures , *CARDIAC arrest , *HEART beat , *RAINBOW trout - Abstract
From an ethical standpoint, it is imperative that rainbow trout (Oncorhynchus mykiss) are humanely slaughtered, which entails that they are rendered unconscious immediately by a stunning method and remain so until death. The efficacy of electrical stunning following dewatering (i.e. , in-air electrical stunning at intensities of 50 to 920 mA and durations of 5 to 30 s) and percussive stunning, both advocated as humane stunning and/or killing methods, are evaluated here for this species via the presence or absence of visually evoked responses (VERs). In addition, ventilatory and cardiac responses were evaluated to elucidate the physiological basis for the lethality of both methods. While the present study was unable to determine the capability of in-air electrical stunning to induce immediate unconsciousness, our findings revealed that irreversible stuns were induced by both in-air electrical stunning (i.e. , ∼25 to 70% of individuals did not recover VERs across the various combinations of stunning intensities and/or durations) and percussive stunning (i.e. , ∼100% of individuals did not recover VERs). The efficacy of in-air electrical stunning for permanently abolishing VERs was marginally, but significantly, impacted by stun intensity (i.e. , explained 8% of the variation). Furthermore, due to substantial inter-specific variability and a limited sample size, significant impacts of stun intensity and/or duration on the recovery of VERs in reversibly stunned individuals were not detected in the present study (i.e. , VERs recovered between <0.5 to 28.8 min). Further investigation is therefore necessary before in-air electrical stunning can be endorsed as a standalone humane slaughter method for rainbow trout. This includes determining its capacity to induce immediate unconsciousness, as well as to identify additional factors that could be modified or enhanced to improve its efficacy. Furthermore, since death following in-air electrical stunning likely entails a prolonged process involving ventilatory failure, hypoxemia, and subsequent vital organ malfunction, rather than immediate cardiac arrest or central nervous system failure, the sequential use of methods such as percussive stunning is recommended to safeguard the welfare of rainbow trout during slaughter. • In-air electrical stunning can induce an irreversible loss of consciousness. • Factors underlying efficacy of electrical stunning require further investigation. • Lethality following electrical stunning is triggered by ventilatory failure. • Percussive stunning halted ventilation instantly, followed by a gradual decrease in heart rate. [ABSTRACT FROM AUTHOR]
- Published
- 2025
- Full Text
- View/download PDF
13. Emotional dysregulation following prenatal stress is associated with altered prefrontal cortex responsiveness to an acute challenge in adolescence.
- Author
-
Orso, Rodrigo, Creutzberg, Kerstin Camile, Begni, Veronica, Petrillo, Giulia, Cattaneo, Annamaria, and Riva, Marco Andrea
- Subjects
- *
PREFRONTAL cortex , *PRENATAL exposure , *HYPOTHALAMIC-pituitary-adrenal axis , *SOCIAL interaction , *ADOLESCENCE - Abstract
Exposure to prenatal stress (PNS) has the potential to elicit multiple neurobiological alterations and increase the susceptibility to psychiatric disorders. Moreover, gestational stress may sensitize the brain toward an altered response to subsequent challenges. Here, we investigated the effects of PNS in rats and assessed whether these animals exhibit an altered brain responsiveness to an acute stress (AS) during adolescence. From gestational day 14 until delivery, Sprague Dawley dams were exposed to PNS or left undisturbed. During adolescence (PND38 to PND41), offspring were tested in the social interaction and splash test. At PND44 half of the animals were exposed to 5 min of forced swim stress. Males and Females exposed to PNS showed reduced sociability and increased anhedonic-like behavior. At the molecular level, exposure of adolescent rats to AS produced increased activation of the amygdala and ventral and dorsal hippocampus. Regarding the prefrontal cortex (PFC), we observed a pronounced activation in PNS males exposed to AS. Cell-type specific transcriptional analyses revealed a significant imbalance in the activation of PFC excitatory and inhibitory neurons in PNS males and females exposed to AS. Furthermore, stressed males exhibited disrupted HPA-axis function, while females showed impairments in the modulation of antioxidant genes. Our study shows that PNS induces emotional dysregulation and alters the responsiveness of the PFC to an acute stressor. Moreover, the disruption of excitatory and inhibitory balance during adolescence could influence the ability to respond to challenging events that may contribute to precipitate a full-blown pathologic condition. • Prenatal stress produces emotional dysregulation in a subset of adolescent animals • Prenatal stress primes the brain for a heightened response to acute stress • Prenatally stressed rats show an imbalanced excitatory/inhibitory responsiveness to acute stress [ABSTRACT FROM AUTHOR]
- Published
- 2025
- Full Text
- View/download PDF
14. Common brain activity features discretization for predicting perceived speech quality.
- Author
-
Parmonangan, Ivan Halim
- Subjects
SPEECH ,FEATURE extraction - Abstract
The synthesized speech quality evaluation is one of the important steps to ensure the generated speech audio sounds good to humans. There are two main approaches to perform the evaluation; subjective and objective. Subjective approaches use human as the assessor, which is the most natural approach. However, it is time-consuming and expensive. Hence, it has generally been replaced by the quicker and cheaper objective approaches. Nevertheless, since objective approaches only analyze the audio features, the predicted quality might not correlated to what humans would perceive. Recent studies shows that brain activity contains some information that can be useful to enhance the prediction performance. This work proposed a method to extract the common features among participants' brain activity to predict the perceived speech audio quality. The result shows that the proposed approach significantly reduces the prediction error. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
15. Relationship between dental occlusion and brain activity: A narrative review.
- Author
-
Silva Ulloa, Sebastian, Cordero Ordóñez, Ana Lucía, and Barzallo Sardi, Vinicio Egidio
- Abstract
Occlusal function stimulates different areas of the cerebral cortex. The purpose of this narrative review was to identify the relationship between occlusion and brain activity so as to provide theoretical support to enable future studies on the subject. Relevant case-control studies, clinical trials, and systematic reviews available in English were retrieved from the following databases: MEDLINE, PubMed, ScienceDirect, Wiley Online Library, and Biblioteca Virtual en Salud (BVS). Of the 53 articles obtained, 12 were included. The sensorimotor cortex is affected by changes in occlusion. It is speculated that occlusion could play an important role in the development of diseases, from anxiety and stress to Alzheimer's disease and senile dementia. Further investigations into the interactions between occlusion and brain function are needed to elucidate the parts of the brain that are affected when occlusion is disturbed and to determine whether brain function is altered. Dentists must consider that alterations in the occlusal pattern during mastication can lead to changes in the activation of different brain regions related to memory, learning, anticipatory pain, and anxiety. This suggests that mastication maintains the integrity of certain brain areas and that it may be a key factor in the onset of neurodegenerative diseases. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
16. A new method of localizing brain activity using the scalp EEG data.
- Author
-
Vartanov, Alexander V.
- Subjects
WAKEFULNESS ,ELECTROENCEPHALOGRAPHY ,SCALP ,STATISTICAL correlation - Abstract
We propose a spatial localization method for scalp electroencephalography (EEG). The technique allows reliable and unambiguous identification of the activity for any intracerebral source by its spatial coordinates. Our "virtually implanted electrode" is based on the dynamics and correlation analysis of signals in the EEG leads with the addition of artificially generated data. The generated data helps us accurately model the electrical potential distribution between the studied source and the scalp electrodes. Each modeled intracerebral source is analyzed independently, so the proposed method does not require an estimate of the possible number of sources. The method produces output values that can be interpreted as the "local field" elec-trical activity for the implanted electrode in the corresponding brain point. The signal cleaning procedure makes it possible to exclude the influence from neighboring regions and detect a given brain region's isolated electrical activity. For verification, the method was applied in the empathy study on a sample of 16 people. We compared the background EEG of calm wakefulness with the EEG of empathic behavior for the 33 preselected brain regions. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
17. Sex-specific signatures of GLP-1 and amylin on resting state brain activity and functional connectivity in awake rats.
- Author
-
Arefin, Tanzil M., Börchers, Stina, Olekanma, Doris, Cramer, Samuel R., Sotzen, Morgan R., Zhang, Nanyin, and Skibicka, Karolina P.
- Subjects
- *
FUNCTIONAL magnetic resonance imaging , *AMYLIN , *FUNCTIONAL connectivity , *FOOD consumption , *DIRECT action , *INGESTION - Abstract
Gut-produced glucagon-like peptide-1 (GLP-1) and pancreas-made amylin robustly reduce food intake by directly or indirectly affecting brain activity. While for both peptides a direct action in the hindbrain and the hypothalamus is likely, few studies examined their impact on whole brain activity in rodents and did so evaluating male rodents under anesthesia. However, both sex and anesthesia may significantly alter the influence of feeding controlling molecules on brain activity. Therefore, we investigated the effect of GLP-1 and amylin on brain activity and functional connectivity (FC) in awake adult male and female rats using resting-state functional magnetic resonance imaging (rsfMRI). We further examined the relationship between the altered brain activity or connectivity and subsequent food intake in response to amylin or GLP-1. We observed sex divergent effects of amylin and GLP-1 on the brain activity and FC patterns. Most importantly correlation analysis between FC and feeding behavior revealed that different brain areas potentially drive reduced food intake in male and female rats. Our findings underscore the distributed and distinctly sex divergent neural network engaged by each of these anorexic peptides and suggest that different brain areas may be the primary drivers of the feeding outcome in male and female rats. Moreover, prominent activity and connectivity alterations observed in brain areas not typically associated with feeding behavior in both sexes may either indicate novel feeding centers or alternatively suggest the involvement of these substances in behaviors beyond feeding and metabolism. The latter question is of potential translational significance as analogues of both amylin and GLP-1 are clinically utilized. • GLP-1 and amylin exert sex divergent effects on the brain activity and functional connectivity patterns. • Different brain areas potentially drive reduced food intake in male and female rats. • Our findings underscore the distributed and distinctly sex divergent neural network engaged by these anorexic peptides. • GLP-1 and amylin altered activity and connectivity in brain areas not typically associated with feeding behavior. • Results highlight potential novel CNS feeding centers or suggest involvement in behaviors beyond feeding and metabolism. [ABSTRACT FROM AUTHOR]
- Published
- 2025
- Full Text
- View/download PDF
18. Brain activity during working memory in patients with autoimmune Addison's disease.
- Author
-
van't Westeinde, Annelies, Padilla, Nelly, Fletcher-Sandersjöö, Sara, Kämpe, Olle, Bensing, Sophie, and Lajic Näreskog, Svetlana
- Subjects
- *
ADDISON'S disease , *SHORT-term memory , *COGNITIVE ability , *MENTAL fatigue , *MENTAL work - Abstract
Autoimmune Addison's disease (AAD) is treated with daily oral hormone replacements for cortisol and aldosterone. The current treatment is sub-optimal, and frequently results in supra- and infra-physiological cortisol levels that might negatively affect the brain and cognitive functioning. It is currently unclear if the brains of these patients need to be better protected. The present study investigates brain function during working memory in young adults with AAD compared to healthy controls. All participants (56 AAD (33 females), 62 controls (39 females), 19–43 years), underwent MRI brain scanning while performing a visuo-spatial and verbal working memory task. No main group differences in accuracy, reaction time or brain activity during the tasks were found. These findings suggest that patients perform equal to controls, and achieve similar levels of brain activity during working memory. However, variations in the patient population may have confounded this outcome. Controlled studies on larger cohorts are therefore needed to confirm these findings and test if having AAD affects the brain on the long term. • Brain activity during verbal and visuo-spatial working memory was assessed in patients with autoimmune Addison's disease. • Patients did not differ from healthy controls in performance on the working memory tasks. • Patients did not differ from healthy controls in brain activity during the working memory tasks. • Patients that experienced more mental fatigue had stronger activity in the cerebellum and occipital cortex. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
19. Use of electroencephalogram (EEG) to optimize stunning efficiency and animal welfare in commercial catfish production.
- Author
-
Hjelmstedt, Per, To, Filip, Gräns, Albin, and Allen, Peter
- Subjects
- *
CHANNEL catfish , *ELECTRIC fishes , *LOSS of consciousness , *ANIMAL welfare , *PHYSICAL measurements , *ELECTROENCEPHALOGRAPHY - Abstract
The welfare of farmed fish has gained increasing attention during recent decades, and as technological advances have facilitated measurements of brain activity in fish, the slaughter process has been highlighted as an area for assessment and potential improvement. Here, we used electroencephalograms (EEG) to assess brain activity in channel catfish (Ictalurus punctatus), and used commercial slaughter practices to guide optimization of stunning conditions in a laboratory setting. Following in-air electro-stunning at processing plants, individual fish responses to the shock varied based on EEG and corresponding ventilation measurements prior to physical euthanasia. Results from laboratory experiments showed stunning efficacy is dependent on shock duration and the location where electrodes contact fish. Electrodes contacting the head for 1 s using 50 Hz 132 AC V RMS , with a current >380 mA RMS , caused immediate loss of consciousness lasting 10–40 s. When the exposure period was prolonged to 6 s, recovery time was significantly longer, ranging from 45 to 240 s (mean 125 s). If the electrodes contacted the body instead of the head, shock delivered for 6 s resulted in a shorter recovery time of 0–100 s (mean 48 s). These findings highlight that shock duration and electrode position are important when stunning channel catfish and presumably other fishes, and indicate the time from stunning to killing should be kept as short as possible. • Electrical stunning can cause unconsciousness in channel catfish. • The effect of electric stunning is often temporary. • Shock duration affect time to recovery. • Electrode position affect time to recovery. • Time between stunning and killing should be kept short. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
20. Non-invasive electroencephalography in awake cats: Feasibility and application to sensory processing in chronic pain.
- Author
-
Delsart, Aliénor, Castel, Aude, Dumas, Guillaume, Otis, Colombe, Lachance, Mathieu, Barbeau-Grégoire, Maude, Lussier, Bertrand, Péron, Franck, Hébert, Marc, Lapointe, Nicolas, Moreau, Maxim, Martel-Pelletier, Johanne, Pelletier, Jean-Pierre, and Troncy, Eric
- Subjects
- *
EVOKED potentials (Electrophysiology) , *SENSORY stimulation , *BLUE light , *CHRONIC pain , *SENSORIMOTOR integration - Abstract
Feline osteoarthritis (OA) leads to chronic pain and somatosensory sensitisation. In humans, sensory exposure can modulate chronic pain. Recently, electroencephalography (EEG) revealed a specific brain signature to human OA. However, EEG pain characterisation or its modulation does not exist in OA cats, and all EEG were conducted in sedated cats, using intradermal electrodes, which could alter sensory (pain) perception. Cats (n =11) affected by OA were assessed using ten gold-plated surface electrodes. Sensory stimuli were presented in random orders: response to mechanical temporal summation, grapefruit scent and mono-chromatic wavelengths (500 nm-blue, 525 nm-green and 627 nm-red light). The recorded EEG was processed to identify event-related potentials (ERP) and to perform spectral analysis (z-score). The procedure was well-tolerated. The ERPs were reported for both mechanical (F3, C3, Cz, P3, Pz) and olfactory stimuli (Cz, Pz). The main limitation was motion artifacts. Spectral analysis revealed a significant interaction between the power of EEG frequency bands and light wavelengths (p <0.001). All wavelengths considered, alpha band proportion was higher than that of delta and gamma bands (p <0.044), while the latter was lower than the beta band (p <0.016). Compared to green and red, exposure to blue light elicited distinct changes in EEG power over time (p <0.001). This is the first demonstration of EEG feasibility in conscious cats with surface electrodes recording brain activity while exposing them to sensory stimulations. The identification of ERPs and spectral patterns opens new avenues for investigating feline chronic pain and its potential modulation through sensory interventions. • Electroencephalography (EEG), using surface electrodes, allowed non-invasive recording of brain activity in conscious cats. • Event-related potentials following mechanical and olfactory stimulations were identified in awake cats using EEG. • Visual stimulations correlated with EEG spectral signatures, showed distinct patterns across different light wavelengths. • This method allows to study brain activity in animals affected by chronic pain and its modulation with sensory stimulation. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
21. Brain and muscle activation patterns during postural control affect static postural control.
- Author
-
Kumai, Ken, Ikeda, Yumi, Sakai, Katsuya, Goto, Keisuke, Morikawa, Kenji, and Shibata, Keiichirou
- Subjects
- *
STATIC pressure , *BIOMECHANICS , *GAIT in humans , *POSTURAL muscles , *INFRARED spectroscopy - Abstract
Background: Previous studies have reported existence of coordinated brain and muscle activity patterns that affect postural control. However, differences in these activity patterns that affect postural control are still unclear. The purpose of this study was to clarify brain and muscle activity pattern affecting postural control.Research Question: Does the difference in brain and muscle activity patterns during postural control affect postural control ability?Method: Nineteen healthy men (mean age: 24.8 ± 4.1 years, height: 171.8 ± 5.5 cm, and weight: 63.5 ± 12.5 kg) performed a postural control task on a balance board, and their brain and muscle activities and body sway during the task were measured using functional near-infrared spectroscopy, surface electromyography, and three-dimensional accelerometry. Hierarchical cluster analysis was conducted to extract subgroups based on brain and muscle activities and postural control, and correlation analysis was performed to investigate the relationship between brain activity, muscle activity, and postural control.Results: Two subgroups were found. Subgroup 1 (n = 9) showed higher brain activity in the supplementary motor area (p = 0.04), primary motor cortex (p = 0.04) and stable postural control in the mediolateral (p < 0.01) planes, and subgroup 2 (n = 10) showed higher muscle activity in the tibialis anterior (p < 0.01), a higher shank muscles co-contraction (p = 0.02) and unstable postural control. Furthermore, the supplementary motor area activity is negatively correlated with body sway of mediolateral plane (r = -0.51, p = 0.02), and tibialis anterior activity is positively correlated with body sway on the mediolateral plane (r = 0.62, p = 0.004).Significance: Higher brain activity in motor-related areas, lower activity in the lower limb muscles and lower co-contraction of shank muscles were observed in stable postural control. These results will facilitate the planning of new rehabilitation methods for improving postural control ability. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
- View/download PDF
22. Functional magnetic resonance imaging of brain activity during hybrid assistive limb intervention in a chronic spinal cord injury patient with C4 quadriplegia.
- Author
-
Saotome, Kousaku, Matsushita, Akira, Eto, Fumihiko, Shimizu, Yukiyo, Kubota, Shigeki, Kadone, Hideki, Ikumi, Akira, Marushima, Aiki, Masumoto, Tomohiko, Koda, Masao, Takahashi, Hiroshi, Miura, Kosei, Matsumura, Akira, Sankai, Yoshiyuki, and Yamazaki, Masashi
- Abstract
• A complete C4 quadriplegia patient underwent gait training using robot suit HAL. • We evaluated his brain activity using task-induced functional MRI. • His cerebral cortex was hyperactive during the imagery task. • His cortical activation was reduced with the progression of the HAL treatment. Hybrid assistive limb (HAL) is a wearable robot, which has recently been used for the treatment of patients with movement disorders including spinal cord injury (SCI). Although several studies have indicated the effectiveness of HAL for SCI patients, changes in brain activity during the HAL intervention have not yet been fully characterized. A 19-year-old man with a chronic SCI resulting in complete C4 quadriplegia underwent five weeks of HAL training for a total of ten sessions. We evaluated his brain activity using task-induced functional MRI (fMRI) after the fourth, sixth and tenth HAL sessions. We also assessed the spasticity of this patient using the modified Ashworth scale (mAs). As controls for the task-induced fMRI, we examined the brain activity in two healthy subjects. The fMRI findings indicated an increased response to a motor imagery task in the patient's cerebral cortex compared to controls. In addition, the activation pattern in his cortex changed during the five weeks of HAL intervention. We observed increased cerebral lateralization in his primary motor cortex. We also found that the laterality index calculated for the precentral gyrus had a significant negative correlation with the total mAs score over the course of the HAL treatment. Our results indicate that the cerebral cortex of the present SCI patient was hyperactive during the imagery task, and the cortical activation was reduced with progression of the HAL treatment. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
23. Effects of short-term Huatou Chan training on health.
- Author
-
Luo, Fei, Qiang, Victor, Wu, Yibing, Wang, Yuzheng, Tian, Wenhong, Ma, Zhiguo, and Mao, Yingying
- Abstract
Previous studies have shown that perennial Chan training leads to improvements in brain functioning. However, few studies have investigated the effects of short-term Huatou Chan training. The current study explored the effects of a three-day Huatou Chan training on physical and emotional health, as well as brain state. Seventy healthy subjects were recruited and divided into two groups: the Huatou Chan group and the Control group. The Huatou Chan group received a 3-day Huatou Chan training, while the Control group waited for three days. Both groups completed a 6 min Brain State Index recording, the SCL-90, the brief profile of mood state, the meaning in life questionnaire, and the Index of Well-being, prior to and after the training or waiting period. Results showed that short-term Huatou Chan training had significant benefits on some aspects such as physical and emotional health (obsessive-compulsive, depression, hostility, and psychoticism), negative emotions (tension-anxiety, depression-dejection, anger-hostility, fatigue-inertia, and confusion-bewilderment), well-being, and attitude towards life. In addition, short-term Chan training can significantly improve brain state, as shown by the index of depression, anxiety, alerting and intelligence. This is the first study to provide direct evidence for the benefits of short-term intensive Huatou Chan training on physical and mental health. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
24. Never too little: Grip and lift forces following probabilistic weight cues in patients with writer's cramp.
- Author
-
Zeuner, Kirsten E., Knutzen, Arne, Granert, Oliver, Trampenau, Leif, Baumann, Alexander, Wolff, Stephan, Jansen, Olav, van Eimeren, Thilo, and Kuhtz-Buschbeck, Johann P.
- Subjects
- *
FOCAL dystonia , *LIFT (Aerodynamics) , *FUNCTIONAL magnetic resonance imaging , *BASAL ganglia - Abstract
[Display omitted] • Patients with writer's cramp do not respond to probabilistic cues indicating that an object will probably be light in a grip-lift task. • The results fit with the pathophysiological concept of a hyperfunctional direct basal ganglia pathway in writer's cramp patients. • Writer's cramp patients' brain activity does not differ significantly from that of control subjects in the grip-lift task with probabilistic cues. Planning of voluntary object-related movements requires the estimation of the most probable object properties. We investigated how 14 writer's cramp (WC) patients compared to 14 controls use probabilistic weight cues in a serial grip-lift task. In every grip-lift trial, an object of either light, medium or heavy weight had to be grasped and lifted after a visual cue gave a probabilistic prediction of the object weights (e.g. 32.5% light, 67.5% medium, 0 % heavy). We determined peak (1) grip force GF, (2) load force LF, (3) grip force rate GFR, (4) load force rate LFR, while we registered brain activity with functional magnetic resonance imaging. In both groups, GFR, LFR and GF increased when a higher probability of heavy weights was announced. When a higher probability of light weights was indicated, controls reduced GFR, LFR and GF, while WC patients did not downscale their forces. There were no inter-group differences in blood oxygenation level dependent activation. WC patients could not utilize the decision range in motor planning and adjust their force in a probabilistic cued fine motor task. The results support the pathophysiological model of a hyperfunctional dopamine dependent direct basal ganglia pathway in WC. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
25. Effective network analysis in music listening based on electroencephalogram.
- Author
-
Tan, Ying, Sun, Zhe, Teng, Xiangbin, Larrouy-Maestri, Pauline, Duan, Feng, and Aoki, Shigeki
- Subjects
- *
MUSICAL analysis , *LARGE-scale brain networks , *PARIETAL lobe , *HUMAN-computer interaction , *LISTENING , *ELECTROENCEPHALOGRAPHY - Abstract
Music is present in every culture and affects humans in numerous ways. Music-related technologies, such as music generation, can extend the application scenarios of human–computer interaction systems. Despite its important role in cognitive and social domains, the brain networks involved in music listening remain unclear. To further explore the relationship between music and brain networks, in this study, we analyzed the brain networks of 29 participants under different musical conditions based on electroencephalogram (EEG) signals. Specifically, we utilized a public dataset that provided EEG signals of participants listening to music under different rhythmic and processing conditions. After EEG source localization, we selected 22 regions of interest (ROIs) that were relevant to music. The effective networks were subsequently established, where the ROIs are regarded as nodes, and the Granger causality relationships between nodes are considered as edges. We explored the differences among these effective networks and analyzed them further based on graph theory. The results demonstrate that different processing methods of music generate changes in the brain network. The results indicate the crucial role of the inferior parietal lobe in information transmission. The findings of this study provide new insights into the relationship between music and brain activity. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
26. Brain activity during walking in older adults: Implications for compensatory versus dysfunctional accounts.
- Author
-
Fettrow, Tyler, Hupfeld, Kathleen, Tays, Grant, Clark, David J., Reuter-Lorenz, Patricia A., and Seidler, Rachael D.
- Subjects
- *
OLDER people , *AGING , *YOUNG adults , *BRAIN imaging , *NEURAL development - Abstract
• We provide an overview of two prevalent conceptual accounts of brain aging. • We assess older adult brain function during walking and evaluate fit with accounts. • Findings suggest different interpretations based on methods and difficulty of task. • We provide suggestions for future aging, locomotion, and imaging experiments. A prominent trend in the functional brain imaging literature is that older adults exhibit increased brain activity compared to young adults to perform a given task. This phenomenon has been extensively studied for cognitive tasks, with the field converging on interpretations described in two alternative accounts. One account interprets over-activation in older adults as reflecting neural dysfunction (increased brain activity – indicates poorer performance), whereas another interprets it as neural compensation (increased brain activity - supports better performance). Here we review studies that have recorded brain activity and walking measurements in older adults, and we categorize their findings as reflecting either neural dysfunction or neural compensation. Based on this synthesis, we recommend including multiple task difficulty levels in future work to help differentiate if and when compensation fails as the locomotion task becomes more difficult. Using multiple task difficulty levels with neuroimaging will lead to a more advanced understanding of how age-related changes in locomotor brain activity fit with existing accounts of brain aging and support the development of targeted neural rehabilitation techniques. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
27. Diets Varying in Carbohydrate Content Differentially Alter Brain Activity in Homeostatic and Reward Regions in Adults.
- Author
-
Holsen, Laura M, Hoge, W Scott, Lennerz, Belinda S, Cerit, Hilâl, Hye, Taryn, Moondra, Priyanka, Goldstein, Jill M, Ebbeling, Cara B, and Ludwig, David S
- Subjects
- *
HIGH-carbohydrate diet , *LOW-carbohydrate diet , *REWARD (Psychology) , *LOW-calorie diet , *WEIGHT loss , *CARBOHYDRATES , *CEREBRAL circulation , *HUNGER - Abstract
Background: Obesity has one of the highest refractory rates of all chronic diseases, in part because weight loss induced by calorie restriction, the first-line treatment for obesity, elicits biological adaptations that promote weight regain. Although acute feeding trials suggest a role for macronutrient composition in modifying brain activity related to hunger and satiety, relevance of these findings to weight-loss maintenance has not been studied.Objectives: We investigated effects of weight-loss maintenance diets varying in macronutrient content on regional cerebral blood flow (rCBF) in brain regions involved in hunger and reward.Methods: In conjunction with a randomized controlled feeding trial, we investigated the effects of weight-loss maintenance diets varying in carbohydrate content [high, 60% of total energy: n = 20; 6 men/14 women; mean age: 32.5 y; mean BMI (in kg/m 2): 27.4; moderate, 40% of total energy: n = 22; 10 men/12 women; mean age: 32.5 y; mean BMI: 29.0; low, 20% of total energy: n = 28; 12 men/16 women; mean age: 33.2 y; mean BMI: 27.7] on rCBF in brain regions involved in hunger and reward preprandial and 4 h postprandial after 14-20 wk on the diets. The primary outcome was rCBF in the nucleus accumbens (NAcc) at 4 h postprandial; the secondary outcome was preprandial rCBF in the hypothalamus.Results: Consistent with a priori hypothesis, at 4 h postprandial, NAcc rCBF was 43% higher in adults assigned to the high- compared with low-carbohydrate diet {P[family-wise error (FWE)-corrected] < 0.05}. Preprandial hypothalamus rCBF was 41% higher on high-carbohydrate diet [P(FWE-corrected) < 0.001]. Exploratory analyses revealed that elevated rCBF on high-carbohydrate diet was not specific to prandial state: preprandial NAcc rCBF [P(FWE-corrected) < 0.001] and 4 h postprandial rCBF in hypothalamus [P(FWE-corrected) < 0.001]. Insulin secretion predicted differential postprandial activation of the NAcc by diet.Conclusions: We report significant differences in rCBF in adults assigned to diets varying in carbohydrate content for several months, which appear to be partially associated with insulin secretion. These findings suggest that chronic intake of a high-carbohydrate diet may affect brain reward and homeostatic activity in ways that could impede weight-loss maintenance. This trial was registered at clinicaltrials.gov as NCT02300857. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF
28. Contrast effects of display colors on Hb concentration changes in the frontal lobe of elderly and young people.
- Author
-
Mohd Anuardi, Muhammad Nur Adilin, Yamazaki, Atsuko K., and Murakami, Kayoko H.
- Subjects
CONTRAST effect ,FRONTAL lobe ,OLDER people ,PSYCHOLOGICAL well-being ,NEAR infrared spectroscopy ,BLUE - Abstract
The combination display of the background color and font is one of the factors that affect psychological functioning. Many studies investigated the contrast effect on psychological well-being in connection with cognitive activity and task performance. These studies including our previous study, demonstrated the significant effects on brain activity and memory task, especially on elderly subjects. In this paper, we further discussed the contrast effects on the brain activity measured in the frontal lobe of young and elderly subjects. We measured hemoglobin (Hb) concentration changes by using near-infrared spectroscopy (NIRS) when the subjects performing the working memory task (reading span task) on three different display background colors (white, blue, green). Elderly subjects had a lower score on the task compared to younger subjects, which expressed a significant effect of aging, but no significant differences between background colors. On the other hand, the increment trend of the cognitive activity throughout the experiment showed task difficulty induced the blood flow in the brain. Between background colors, the brain activity of the young subject had a negative correlation on the contrast ratio where the low contrast ratio activated their brain activity the most. However, the elderly subject had the opposite results where the higher the contrast ratio, the more activation occurred in their brain. In conclusion, our finding is a key needed to keep activating the brain of elderly people where it tends to experience ability deterioration. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
29. Effects of the unilateral dynamic handgrip on resting cortical activity levels: A replication and extension.
- Author
-
Mirifar, Arash, Cross-Villasana, Fernando, Beckmann, Jürgen, and Ehrlenspiel, Felix
- Subjects
- *
FREQUENCY spectra , *MUSCLE contraction , *SCALP , *ELECTRODES - Abstract
Previous studies have linked unilateral hand contractions to subsequent changes in hemispheric asymmetric activity, as reflected in the electroencephalographic alpha (8–12 Hz) range in each hemisphere. However, debate continues regarding the state of asymmetry induced by unilateral contractions. We have previously found a bilateral enhancement of alpha amplitude that occurs after contractions, reflecting cortical downregulation instead of changes in asymmetric activity. To corroborate our observations, we examined the effects of 45 s of unilateral dynamic handgrip contractions on subsequent resting alpha activity. Twenty-two right-handed participants were recruited (M = 25 years, 17 female). The study used a within-subjects design consisting of a pre- and post-test (2 min resting; eyes open) for the intervention (dynamic handgrip; at a self-determined pace of approximately twice a second for 45 s for each hand). Following the handgrip task, an increase in alpha amplitude above the baseline was observed over the entire cortex, which was greater after left-hand squeezing. This observation confirms our previous findings and we have extended them by adding more electrodes to gain further insights into the handgrip exercise as an external brain stimulator. Moreover, we grouped electrodes according to scalp regions to facilitate the visualization of the effects on the frequency spectrum. Our findings can be used to develop targeted interventions aimed at modifying behavioral outcomes affected by alpha activity. • A significant increase in alpha amplitude above the baseline observed only after left-hand squeezing. • Left-hand may trigger a greater inhibitory reaction due to more wide connectivity of the right-hemisphere across the brain. • These results might proposed mechanism underlying the behavioral observations reported in handgrip experiments. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
30. Atlas of exercise-induced brain activation in mice.
- Author
-
Skovbjerg, Grethe, Fritzen, Andreas Mæchel, Svendsen, Charlotte Sashi Aier, Perens, Johanna, Skytte, Jacob Lercke, Lund, Camilla, Lund, Jens, Madsen, Martin Rønn, Roostalu, Urmas, Hecksher-Sørensen, Jacob, and Clemmensen, Christoffer
- Abstract
There is significant interest in uncovering the mechanisms through which exercise enhances cognition, memory, and mood, and lowers the risk of neurodegenerative diseases. In this study, we utilize forced treadmill running and distance-matched voluntary wheel running, coupled with light sheet 3D brain imaging and c-Fos immunohistochemistry, to generate a comprehensive atlas of exercise-induced brain activation in mice. To investigate the effects of exercise on brain activity, we compared whole-brain activation profiles of mice subjected to treadmill running with mice subjected to distance-matched wheel running. Male mice were assigned to one of four groups: a) an acute bout of voluntary wheel running, b) confinement to a cage with a locked running wheel, c) forced treadmill running, or d) placement on an inactive treadmill. Immediately following each exercise or control intervention, blood samples were collected for plasma analysis, and brains were collected for whole-brain c-Fos quantification. Our dataset reveals 255 brain regions activated by acute exercise in mice, the majority of which have not previously been linked to exercise. We find a broad response of 140 regulated brain regions that are shared between voluntary wheel running and treadmill running, while 32 brain regions are uniquely regulated by wheel running and 83 brain regions uniquely regulated by treadmill running. In contrast to voluntary wheel running, forced treadmill running triggers activity in brain regions associated with stress, fear, and pain. Our findings demonstrate a significant overlap in neuronal activation signatures between voluntary wheel running and distance-matched forced treadmill running. However, our analysis also reveals notable differences and subtle nuances between these two widely used paradigms. The comprehensive dataset is accessible online at www.neuropedia.dk , with the aim of enabling future research directed towards unraveling the neurobiological response to exercise. • 3D imaging and c-Fos immunohistochemistry uncover activation in 255 brain regions following acute exercise in mice. • Voluntary wheel running and forced treadmill running have overlapping and distinct neuronal activation patterns. • Forced treadmill running triggers activation in brain regions linked to stress, pain, and fear. • Access the online activity-induced brain map resource at www.neuropedia.dk. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
31. Activity of mirror neurons in man in the observation, pronunciation and mental pronunciation of words.
- Author
-
Bushov, Yury, Ushakov, Vadim, Svetlik, Mikhail, Esipenko, Elena, Kartashov, Sergey, Orlov, Vyacheslav, and Malakhov, Denis
- Subjects
VOXEL-based morphometry ,MIRROR neurons ,FUNCTIONAL magnetic resonance imaging ,PRONUNCIATION - Abstract
The purpose of this study was to investigate the activity of mirror neurons in humans during observation, pronunciation and mental pronunciation of emotional and neutral words depending on the lateral organization of the brain. To achieve this goal, the methods of electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) were used to examine brain activity in young men when observing, pronouncing and mental pronouncing emotional and neutral words. EEG was recorded monopolar using a 24-channel encephalograph-analyzer "Encephalan-131-03" (Medicom, Taganrog, Russia), fMRI were obtained on a 3 T Magnetom Verio tomograph (Siemens). Research have shown that the performance of activities related to observation, pronouncing and mental pronouncing of words is accompanied by a depression of the mu rhythm and, most often, increased levels of cortical communication at the frequency of this rhythm between the central and frontal, temporal, parietal and occipital zones of brain. The results of fMRI - studies showed the participation of a complex of structures represented by neurons of the left inferior frontal gyrus, the right posterior region of the middle temporal gyrus, and the right region of the angular gyrus, which, presumably, is part of the system of mirror neurons and the complex of structures represented by the neurons of the area of precuneus right areas of the gyrus, which are likely to be part of the system of production of speech directly in the provision of cognitive activity associated with observation, associated with the observation, pronunciation and mental pronunciation of emotional and neutral words. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
32. Structural and functional alterations in the brain gray matter among first-degree relatives of schizophrenia patients: A multimodal meta-analysis of fMRI and VBM studies.
- Author
-
Saarinen, Aino I.L., Huhtaniska, Sanna, Pudas, Juho, Björnholm, Lassi, Jukuri, Tuomas, Tohka, Jussi, Granö, Niklas, Barnett, Jennifer H., Kiviniemi, Vesa, Veijola, Juha, Hintsanen, Mirka, and Lieslehto, Johannes
- Subjects
- *
PEOPLE with schizophrenia , *SCHIZOPHRENIA , *FUNCTIONAL magnetic resonance imaging , *VOXEL-based morphometry , *META-analysis , *GRAY matter (Nerve tissue) , *BRAIN , *SOCIAL participation , *MAGNETIC resonance imaging , *BRAIN mapping , *PSYCHOLOGICAL tests - Abstract
Objective: We conducted a multimodal coordinate-based meta-analysis (CBMA) to investigate structural and functional brain alterations in first-degree relatives of schizophrenia patients (FRs).Methods: We conducted a systematic literature search from electronic databases to find studies that examined differences between FRs and healthy controls using whole-brain functional magnetic resonance imaging (fMRI) or voxel-based morphometry (VBM). A CBMA of 30 fMRI (754 FRs; 959 controls) and 11 VBM (885 FRs; 775 controls) datasets were conducted using the anisotropic effect-size version of signed differential mapping. Further, we conducted separate meta-analyses about functional alterations in different cognitive tasks: social cognition, executive functioning, working memory, and inhibitory control.Results: FRs showed higher fMRI activation in the right frontal gyrus during cognitive tasks than healthy controls. In VBM studies, there were no differences in gray matter density between FRs and healthy controls. Furthermore, multi-modal meta-analysis obtained no differences between FRs and healthy controls. By utilizing the BrainMap database, we showed that the brain region which showed functional alterations in FRs (i) overlapped only slightly with the brain regions that were affected in the meta-analysis of schizophrenia patients and (ii) correlated positively with the brain regions that exhibited increased activity during cognitive tasks in healthy individuals.Conclusions: Based on this meta-analysis, FRs may exhibit only minor functional alterations in the brain during cognitive tasks, and the alterations are much more restricted and only slightly overlapping with the regions that are affected in schizophrenia patients. The familial risk did not relate to structural alterations in the gray matter. [ABSTRACT FROM AUTHOR]- Published
- 2020
- Full Text
- View/download PDF
33. Toward a theory of consciousness: A review of the neural correlates of inattentional blindness.
- Author
-
Hutchinson, Brendan T.
- Subjects
- *
CONSCIOUSNESS , *BLINDNESS - Abstract
• Research on inattentional blindness (IB) with neural measures is reviewed. • Intermediate stages of visual processing reliably occur during IB. • IB research favours visual awareness negativity over p300 as a marker of awareness. • Temporoparietal junction and intra-parietal sulcus are implicated in IB. • More work is needed to establish the reliability of reported correlates. The neuroscientific study of consciousness involves examining candidate markers of consciousness under conditions where awareness varies. One such method for manipulating awareness is inattentional blindness. Whereas other methods of studying consciousness have been reviewed elsewhere, there has been little effort toward cataloguing work which has studied inattentional blindness using neuroscientific methodology. I address this by reviewing this body of literature, with key importance placed on how research informs a neuroscience of consciousness and the degree to which visual processing occurs in the absence of attention and awareness. Findings demonstrate clear evidence that processing up to intermediate stages (e.g. visual features, orthographic processing) occurs, even during inattentional blindness. The most commonly observed neurophysiological correlates associated with awareness include the visual awareness negativity and post-stimulus alpha suppression, whereas neuroanatomical markers include the lateral occipital cortex, the temporoparietal junction, and the intraparietal sulcus. I conclude by addressing the limitations this literature has been challenged with and offer recommendations for how future work on inattentional blindness can aid in advancing neuroscientific theories of consciousness. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
34. An unsupervised EEG decoding system for human emotion recognition.
- Author
-
Liang, Zhen, Oba, Shigeyuki, and Ishii, Shin
- Subjects
- *
EMOTION recognition , *EMOTIONS , *EMOTIONAL conditioning , *BRAIN-computer interfaces , *EMOTIONAL state , *ELECTROENCEPHALOGRAPHY - Abstract
Emotion plays a vital role in human health and many aspects of life, including relationships, behaviors and decision-making. An intelligent emotion recognition system may provide a flexible method to monitor emotion changes in daily life and send warning information when unusual/unhealthy emotional states occur. Here, we proposed a novel unsupervised learning-based emotion recognition system in an attempt to decode emotional states from electroencephalography (EEG) signals. Four dimensions of human emotions were examined: arousal, valence, dominance and liking. To better characterize the trials in terms of EEG features, we used hypergraph theory. Emotion recognition was realized through hypergraph partitioning, which divided the EEG-based hypergraph into a specific number of clusters, with each cluster indicating one of the emotion classes and vertices (trials) in the same cluster sharing similar emotion properties. Comparison of the proposed unsupervised learning-based emotion recognition system with other recognition systems using a well-known public emotion database clearly demonstrated the validity of the proposed system. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
35. The brain during free movement – What can we learn from the animal model.
- Author
-
Händel, B.F. and Schölvinck, M.L.
- Subjects
- *
ANIMAL mechanics , *LEARNING in animals , *ANIMAL models in research , *BRAIN , *LABORATORY animals , *FREEDOM of expression - Abstract
• Animals' need to move forces neuroscientists to record from the brain in motion. • Most neural recording techniques have been adapted to record from the moving brain. • Free movement of animals plays a vital role in many cognitive functions. • Viewed as an active behavioural state, it also impacts brain function in general. • In summary, animal research is very valuable to research on the human moving brain. Animals, just like humans, can freely move. They do so for various important reasons, such as finding food and escaping predators. Observing these behaviors can inform us about the underlying cognitive processes. In addition, while humans can convey complicated information easily through speaking, animals need to move their bodies to communicate. This has prompted many creative solutions by animal neuroscientists to enable studying the brain during movement. In this review, we first summarize how animal researchers record from the brain while an animal is moving, by describing the most common neural recording techniques in animals and how they were adapted to record during movement. We further discuss the challenge of controlling or monitoring sensory input during free movement. However, not only is free movement a necessity to reflect the outcome of certain internal cognitive processes in animals, it is also a fascinating field of research since certain crucial behavioral patterns can only be observed and studied during free movement. Therefore, in a second part of the review, we focus on some key findings in animal research that specifically address the interaction between free movement and brain activity. First, focusing on walking as a fundamental form of free movement, we discuss how important such intentional movements are for understanding processes as diverse as spatial navigation, active sensing, and complex motor planning. Second, we propose the idea of regarding free movement as the expression of a behavioral state. This view can help to understand the general influence of movement on brain function. Together, the technological advancements towards recording from the brain during movement, and the scientific questions asked about the brain engaged in movement, make animal research highly valuable to research into the human "moving brain". [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
36. Altered brain functional connectivity and correlation with psychological status in patients with unilateral pulsatile tinnitus.
- Author
-
Xu, Yaping
- Subjects
- *
FUNCTIONAL magnetic resonance imaging , *BRAIN , *CAUDATE nucleus , *CEREBELLUM , *THALAMUS , *SLEEP , *PSYCHOACOUSTICS - Abstract
• Increased ALFF was found in the left cerebellum and left ITG in PT patients by rs-fMRI. • An increased FC was focused on the left cerebellum and ITG, right STG and occipital gyrus; the ITG and the thalamus in PT patients. • A negative relationship was noted between the values of PSQI, SAS and FC in the ITG and the thalamus in PT patients. The study investigated the alteration of brain functional connectivity (FC) patterns and analyzed the relationship between FC and psychological statue in pulsatile tinnitus (PT) patients by resting-state functional magnetic resonance imaging. The eligible PT patients (29) and healthy subjects (29) were enrolled. Brain activity, FC and clinical characteristics, including tinnitus handicap inventory, duration, sleep quality, anxiety, and depression were evaluated. A significantly increased brain activity in the left cerebellum and left inferior temporal gyrus was observed in PT patients. An abnormally increased FC was focused on the left cerebellum and left inferior temporal gyrus, right superior temporal gyrus, and right occipital gyrus, as well as, the inferior temporal gyrus and thalamus, the putamen and caudate nucleus. Decreased FC was demonstrated between the left cerebellum and bilateral angular gyrus, as well as, the left inferior temporal gyrus and orbital gyrus of the medial prefrontal lobe. A negative correlation was established between the scores of sleep quality and anxiety and the values of FC (in the inferior temporal gyrus and bilateral thalamus). These results suggest an abnormal activity of non-auditory cortex (the cerebellum and inferior temporal gyrus), and the alteration of FC patterns are responsible for PT. Some psychological factors may not be correlated with FC in PT patients. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
37. Analysis of Frontal Cerebral Blood Flow Changes in Hand Grip Force Adjustment Skill Learning.
- Author
-
Miura, Hirokazu, Hakoda, Masahiro, Matsuda, Noriyuki, and Taki, Hirokazu
- Subjects
CEREBRAL circulation ,MOTOR learning ,RECURRENT neural networks ,MULTIPLE correspondence analysis (Statistics) ,ABILITY ,PREFRONTAL cortex - Abstract
Human beings perform various motion ranging from simple motion to advanced motion. In addition, sensory information is used as a feedback information of the motion state during operations which require fine adjustment. It is necessary for performing advanced motion to acquire the corresponding skills. To learn such skills efficiently, it is necessary to construct a skill learning system. Grasping skill acquisition status is effective for the skill learning system. Currently, there is no other method than evaluating skill acquisition status by using learners' task scores. However, this method may not be enough to evaluate skill acquisition status. On the other hand, brain has the function of motion commands and sensory acceptance when moving the body. Therefore, it might be possible to sufficiently evaluate skill acquisition status by using the changes of brain activity. In the paper, we measured the changes of cerebral blood flow on learning of force adjustment skill. The obtained data was analyzed by principal component analysis (PCA) and Recurrent Neural Network (RNN). The result of PCA shows that there are some channels which have the changes of the principal component score before and after learning. In the classification by RNN, when the first principal component scores of the cerebral blood flow data before and after learning were used for input data, high classification accuracy was obtained. In addition, higher classification accuracy was obtained when using only channels which have changes in the principal component scores before and after the learning are used as input data, rather than all channels were inputted. From these results, it is shown that characteristics of the prefrontal cerebral blood flow changes according to the motor skill learning. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
38. The effects of flight complexity on gaze entropy: An experimental study with fighter pilots.
- Author
-
Diaz-Piedra, Carolina, Rieiro, Hector, Cherino, Alberto, Fuentes, Luis J., Catena, Andres, and Di Stasi, Leandro L.
- Subjects
- *
FIGHTER pilots , *TASK performance , *REGULATION of gaze , *ELECTROENCEPHALOGRAPHY , *EYE tracking - Abstract
We studied the effects of task load variations as a function of flight complexity on combat pilots' gaze behavior (i.e., entropy) while solving in-flight emergencies. The second company of the Spanish Army Attack Helicopter Battalion (n = 15) performed three sets of standardized flight exercises with different levels of complexity (low [recognition flights], medium and high [emergency flights]). Throughout the flight exercises we recorded pilots' gaze entropy, as well as pilots' performance (assessed by an expert flight instructor) and subjective ratings of task load (assessed by the NASA-Task Load Index). Furthermore, we used pilots' electroencephalographic (EEG) activity as a reference physiological index for task load variations. We found that pilots' gaze entropy decreased ∼2% (i.e., visual scanning became less erratic) while solving the emergency flight exercises, showing a significant decreasing trend with increasing complexity (p < .05). This is in consonance with the ∼12% increase in the frontal theta band of their EEG spectra during said exercises. Pilots' errors and subjective ratings of task load increased as flight complexity increased (p-values < .05). Gaze data suggest that pilots used nondeterministic visual patterns when the aircraft was in an error-free state (low complexity), and changed their scanning behavior, becoming more deterministic, once emergencies occurred (medium/high complexity). Overall, our findings indicate that gaze entropy can serve as a sensitive index of task load in aviation settings. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
39. Electrophysiological correlates of the emotional response on brain activity in adolescents.
- Author
-
Mesa-Gresa, Patricia, Gil-Gómez, Jose-Antonio, Lozano-Quilis, Jose Antonio, Schoeps, Konstanze, and Montoya-Castilla, Inmaculada
- Subjects
YOUNG adults ,BETA rhythm ,TEENAGERS ,ELECTROPHYSIOLOGY ,THETA rhythm ,AFFECTIVE neuroscience ,NEUROPHYSIOLOGY - Abstract
Many studies have attempted to analyze the main neurophysiological characteristics of emotional response, but few have been carried out at early ages, including adolescence or early adulthood. The main objective of the present study is to assess the electrophysiological correlates of emotional response in adolescents and young adults through electroencephalography (EEG) measures. Sample, composed of 25 subjects (18.44 ± 0.71 years old), were exposed to different sequences of images belonging to the IAPS, which were selected following the dimensional model, based on their valence and arousal, while their neural activity was evaluated through EEG. Results indicated differences in cortical neural activity in response to the valence of the images and the level of arousal. Specifically, we observed that exposure to positive images (high valence) with high arousal produced an increase in alpha, beta, and delta wave activity but not in theta activity. In the case of positive images with low arousal, however, the results indicated an increase in beta waves only and a decrease in alpha, delta, and theta activity. For negative images (low valence) with high arousal, an increase in alpha, beta, and delta waves but not in theta was observed, while negative images with low arousal induced an increase in beta, delta, and theta wave response. This study demonstrates that activated cortical areas indicated significant differences based on the different emotional responses in adolescents and young adults. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
40. Using cortico-muscular and cortico-cardiac coherence to study the role of the brain in the development of muscular fatigue.
- Author
-
Martínez-Aguilar, Gloria Mónica and Gutiérrez, David
- Subjects
MUSCLE fatigue ,CYCLING ,EXERCISE ,BRAIN waves ,ELECTROENCEPHALOGRAPHY ,ELECTROMYOGRAPHY ,ELECTROCARDIOGRAPHY - Abstract
Highlights • We propose a method to analyze cortico-muscular and cortico-cardiac coupling during a cycling exercise in order to study the development of muscular fatigue. • The proposed experimental protocol allows any person to be assessed based on their own individualized fatigue thresholds, then our proposal can be used not only for training, but also for clinical purposes. • We use the coherence as a metric to understand the coupling between electroencephalography, electromyography, and electrocardiography signals, then we relate such coupling to the influence that performance fatigability and the perception of fatigue may have between each other. Abstract We propose a method to analyze cortico-muscular and cortico-cardiac coupling during a cycling exercise in order to study the development of muscular fatigue. Our analysis is based in finding statistically significant changes in the coherence between electromyography (EMG) and electrocardiography (ECG) when compared against electroencephalography (EEG) signals. The coherence is a measure of the degree of correlation of the spectral power in an specified bandwidth between two signals, then EMG-EEG and ECG-EEG coherences are here analyzed during the development of muscular fatigue. For that purpose, we propose an experimental protocol in which a personalized fatigue threshold is found for the volunteers, then different levels of physical exertion are considered. Our results showed significant changes in the maximum cortico-muscular coherence in the β brain rhythm as the exercise progresses and fatigue develops, as well as changes in the maximum cortico-cardiac coherence, again in the β band, from the beginning to the end of the exercise protocol. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
41. Characterization of electroencephalography signals for estimating saliency features in videos.
- Author
-
Liang, Zhen, Hamada, Yasuyuki, Oba, Shigeyuki, and Ishii, Shin
- Subjects
- *
VIDEOS , *ELECTROENCEPHALOGRAPHY , *VISUAL perception , *AUDIOVISUAL materials , *ELECTRODIAGNOSIS - Abstract
Understanding the functions of the visual system has been one of the major targets in neuroscience for many years. However, the relation between spontaneous brain activities and visual saliency in natural stimuli has yet to be elucidated. In this study, we developed an optimized machine learning-based decoding model to explore the possible relationships between the electroencephalography (EEG) characteristics and visual saliency. The optimal features were extracted from the EEG signals and saliency map which was computed according to an unsupervised saliency model ( Tavakoli and Laaksonen, 2017 ). Subsequently, various unsupervised feature selection/extraction techniques were examined using different supervised regression models. The robustness of the presented model was fully verified by means of ten-fold or nested cross validation procedure, and promising results were achieved in the reconstruction of saliency features based on the selected EEG characteristics. Through the successful demonstration of using EEG characteristics to predict the real-time saliency distribution in natural videos, we suggest the feasibility of quantifying visual content through measuring brain activities (EEG signals) in real environments, which would facilitate the understanding of cortical involvement in the processing of natural visual stimuli and application developments motivated by human visual processing. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
42. Effects of teaching the concept of neuroplasticity to induce a growth mindset on motivation, achievement, and brain activity: A meta-analysis.
- Author
-
Sarrasin, Jérémie Blanchette, Nenciovici, Lucian, Foisy, Lorie-Marlène Brault, Allaire-Duquette, Geneviève, Riopel, Martin, and Masson, Steve
- Abstract
Inducing a growth mindset in students has been shown to impact positively on motivation, academic achievement, and brain activity. However, some studies have yielded different results and authors rarely provide reasons to explain this inconsistency. In an effort to better understand the conflicting evidence, we conducted a meta-analysis of 10 peer-reviewed studies including participants from age 7 to adulthood. Results show that inducing a growth mindset by teaching neuroplasticity has an overall positive effect on motivation, achievement, and brain activity. The results also reveal that this intervention seems more beneficial for at-risk students, especially regarding mathematics achievement. These findings thus suggest that inconsistent evidence across empirical studies could be explained by students’ characteristics and subject area. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
43. Brain activity, low self-control, and delinquency: An fMRI study of at-risk adolescents.
- Author
-
Meldrum, Ryan Charles, Trucco, Elisa M., Cope, Lora M., Zucker, Robert A., and Heitzeg, Mary M.
- Subjects
- *
SELF-control in adolescence , *DELINQUENT behavior , *FUNCTIONAL magnetic resonance imaging , *CRIMINOLOGISTS , *PSYCHOLOGICAL adaptation - Abstract
Purpose A vast literature finds that low self-control is associated with a myriad of antisocial behaviors. Consequently, increasing attention has focused on the causes of low self-control. While criminologists have directed significant attention to studying its social causes, fewer studies have considered its neural bases. Methods We add to this nascent body of research by using data collected on an at-risk sample of adolescents participating in the ongoing Michigan Longitudinal Study. We examine the functioning of prefrontal and limbic regions of the brain during failed inhibitory control, assessed using the go/no-go task and functional magnetic resonance imaging, in relation to low self-control and self-reported delinquency. Results Results indicate that greater activation localized in the anterior cingulate cortex (ACC) during failed inhibitory control is negatively associated with low self-control. Moreover, the association between ACC activity and later delinquency is mediated through low self-control. Conclusions Findings of this study demonstrate the utility of integrating neuroscientific and criminological perspectives on the causes of antisocial behavior. Concluding remarks address the theoretical and policy implications of the findings, as well as directions for future research. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
44. Neurophysiological, muscular, and perceptual adaptations of exoskeleton use over days during overhead work with competing cognitive demands.
- Author
-
Tyagi, Oshin, Rana Mukherjee, Tiash, and Mehta, Ranjana K.
- Subjects
- *
NEUROPHYSIOLOGY , *SKELETON physiology , *COGNITIVE ability , *ELECTROMYOGRAPHY , *NEUROERGONOMICS - Abstract
This study captured neurophysiological, muscular, and perceptual adaptations to shoulder exoskeleton use during overhead work with competing physical-cognitive demands. Twenty-four males and females, randomly divided into control and exoskeleton groups, performed an overhead reaching and pointing task over three days without (single task) and with (dual task) a working memory task. Task performance, electromyography (EMG), neural activity, heart rate, and subjective responses were collected. While task completion time reduced for both groups at the same rate over days, EMG activity of shoulder muscles was lower for the exoskeleton group for both tasks, specifically for females during the dual task. Dual task reduced the physiological benefits of exoskeletons and neuromotor strategies to adapt to the dual task demands differed between the groups. Neuromuscular benefits of exoskeleton use were immediately realized irrespective of cognitive demand, however the perceptual, physiological, and neural adaptations with exoskeleton use were task- and sex-specific. • Sex differences in muscular effort during overhead tasks diminish with exoskeleton use. • Exoskeleton-related physiological adaptation during overhead tasks is longer in women. • Physiological benefits of exoskeleton use diminish with dual task demands. • Wearers don't perceive exoskeleton benefits with dual task demands. • Exoskeleton-related neural adaptation strategies differ with dual task demands. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
45. EEG-based classification of individuals with neuropsychiatric disorders using deep neural networks: A systematic review of current status and future directions.
- Author
-
Parsa, Mohsen, Rad, Habib Yousefi, Vaezi, Hadi, Hossein-Zadeh, Gholam-Ali, Setarehdan, Seyed Kamaledin, Rostami, Reza, Rostami, Hana, and Vahabie, Abdol-Hossein
- Subjects
- *
ARTIFICIAL neural networks , *DEEP learning , *NEUROBEHAVIORAL disorders , *MACHINE learning , *ALZHEIMER'S disease , *CONVOLUTIONAL neural networks , *DEEP brain stimulation - Abstract
• Comprehensive review of deep learning studies using EEG signals for neuropsychiatric disorder classification. • Analysis of factors impacting classification performance and guidelines for EEG-based diagnostic tool design. • Emphasis on EEG feature extraction for improved classification and need for further research on interpretable features. • Potential of deep neural networks for accurate neuropsychiatric disorder diagnosis using EEG signals. The use of deep neural networks for electroencephalogram (EEG) classification has rapidly progressed and gained popularity in recent years, but automatic feature extraction from EEG signals remains a challenging task. The classification of neuropsychiatric disorders demands the extraction of neuro-markers for use in automated EEG classification. Numerous advanced deep learning algorithms can be used for this purpose. In this article, we present a comprehensive review of the main factors and parameters that affect the performance of deep neural networks in classifying different neuropsychiatric disorders using EEG signals. We also analyze the EEG features used for improving classification performance. Our analysis includes 82 scientific journal papers that applied deep neural networks for subject-wise classification based on EEG signals. We extracted information on the EEG dataset and types of disorders, deep neural network structures, performance, and hyperparameters. The results show that most studies have focused on clinical classification, achieving an average accuracy of 91.83 ± 7.34, with convolutional neural networks (CNNs) being the most frequently used network architecture and resting-state EEG signals being the most commonly used data type. Additionally, the review reveals that depression (N = 18), Alzheimer's (N = 11), and schizophrenia (N = 11) were studied more frequently than other types of neuropsychiatric disorders. Our review provides insight into the performance of deep neural networks in EEG classification and highlights the importance of EEG feature extraction in improving classification accuracy. By identifying the main factors and parameters that affect deep neural network performance in EEG classification, our review can guide future research in this area. We hope that our findings will encourage further exploration of deep learning methods for EEG classification and contribute to the development of more accurate and effective methods for diagnosing and monitoring neuropsychiatric disorders using EEG signals. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
46. Nonlinear dynamical analysis of sleep electroencephalography using fractal and entropy approaches.
- Author
-
Ma, Yan, Shi, Wenbin, Peng, Chung-Kang, and Yang, Albert C.
- Abstract
The analysis of electroencephalography (EEG) recordings has attracted increasing interest in recent decades and provides the pivotal scientific tool for researchers to quantitatively study brain activity during sleep, and has extended our knowledge of the fundamental mechanisms of sleep physiology. Conventional EEG analyses are mostly based on Fourier transform technique which assumes linearity and stationarity of the signal being analyzed. However, due to the complex and dynamical characteristics of EEG, nonlinear approaches are more appropriate for assessing the intrinsic dynamics of EEG and exploring the physiological mechanisms of brain activity during sleep. Therefore, this article introduces the most commonly used nonlinear methods based on the concepts of fractals and entropy, and we review the novel findings from their clinical applications. We propose that nonlinear measures may provide extensive insights into brain activities during sleep. Further studies are proposed to mitigate the limitations and to expand the applications of nonlinear EEG analysis for a more comprehensive understanding of sleep dynamics. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
47. Brain activation during processing of genuine facial emotion in depression: Preliminary findings.
- Author
-
Groves, Samantha J., Pitcher, Toni L., Melzer, Tracy R., Jordan, Jennifer, Carter, Janet D., Malhi, Gin S., Johnston, Lucy C., and Porter, Richard J.
- Subjects
- *
FACIAL expression & psychology , *DEPRESSED persons , *FUNCTIONAL magnetic resonance imaging , *PREFRONTAL cortex , *CINGULATE cortex , *PHYSIOLOGY , *BRAIN , *CEREBRAL cortex , *MENTAL depression , *FACIAL expression , *FRONTAL lobe , *HAPPINESS , *LIMBIC system , *MAGNETIC resonance imaging , *PARIETAL lobe , *TASK performance , *CASE-control method - Abstract
Objective: The current study aimed to examine the neural correlates of processing genuine compared with posed emotional expressions, in depressed and healthy subjects using a novel functional magnetic resonance imaging (fMRI) paradigm METHOD: During fMRI scanning, sixteen depressed patients and ten healthy controls performed an Emotion Categorisation Task, whereby participants were asked to distinguish between genuine and non-genuine (posed or neutral) facial displays of happiness and sadness.Results: Compared to controls, the depressed group showed greater activation whilst processing genuine versus posed facial displays of sadness, in the left medial orbitofrontal cortex, caudate and putamen. The depressed group also showed greater activation whilst processing genuine facial displays of sadness relative to neutral displays, in the bilateral medial frontal/orbitofrontal cortex, left dorsolateral prefrontal cortex, right dorsal anterior cingulate, bilateral posterior cingulate, right superior parietal lobe, left lingual gyrus and cuneus. No differences were found between the two groups for happy facial displays.Limitations: Relatively small sample sizes and due to the exploratory nature of the study, no correction was made for multiple comparisons.Conclusion: The findings of this exploratory study suggest that depressed individuals may show a different pattern of brain activation in response to genuine versus posed facial displays of sadness, compared to healthy individuals. This may have important implications for future studies that wish to examine the neural correlates of facial emotion processing in depression. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
48. Monitoring driver fatigue using a single-channel electroencephalographic device: A validation study by gaze-based, driving performance, and subjective data.
- Author
-
Morales, José M., Díaz-Piedra, Carolina, Rieiro, Héctor, Roca-González, Joaquín, Romero, Samuel, Catena, Andrés, Fuentes, Luis J., and Di Stasi, Leandro L.
- Subjects
- *
ELECTROENCEPHALOGRAPHY , *AUTOMOBILE driving , *AUTOMOBILE drivers , *WEARABLE technology , *FATIGUE (Physiology) - Abstract
Driver fatigue can impair performance as much as alcohol does. It is the most important road safety concern, causing thousands of accidents and fatalities every year. Thanks to technological developments, wearable, single-channel EEG devices are now getting considerable attention as fatigue monitors, as they could help drivers to assess their own levels of fatigue and, therefore, prevent the deterioration of performance. However, the few studies that have used single-channel EEG devices to investigate the physiological effects of driver fatigue have had inconsistent results, and the question of whether we can monitor driver fatigue reliably with these EEG devices remains open. Here, we assessed the validity of a single-channel EEG device (TGAM-based chip) to monitor changes in mental state (from alertness to fatigue). Fifteen drivers performed a 2-h simulated driving task while we recorded, simultaneously, their prefrontal brain activity and saccadic velocity. We used saccadic velocity as the reference index of fatigue. We also collected subjective ratings of alertness and fatigue, as well as driving performance. We found that the power spectra of the delta EEG band showed an inverted U-shaped quadratic trend (EEG power spectra increased for the first hour and half, and decreased during the last thirty minutes), while the power spectra of the beta band linearly increased as the driving session progressed. Coherently, saccadic velocity linearly decreased and speeding time increased, suggesting a clear effect of fatigue. Subjective data corroborated these conclusions. Overall, our results suggest that the TGAM-based chip EEG device is able to detect changes in mental state while performing a complex and dynamic everyday task as driving. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
49. Not in one metric: Neuroticism modulates different resting state metrics within distinctive brain regions.
- Author
-
Gentili, Claudio, Cristea, Ioana Alina, Ricciardi, Emiliano, Vanello, Nicola, Popita, Cristian, David, Daniel, and Pietrini, Pietro
- Subjects
- *
AFFECTIVE disorders , *NEUROTICISM , *BRAIN imaging , *BRAIN function localization , *FUNCTIONAL magnetic resonance imaging , *PERSONALITY questionnaires , *DIAGNOSIS - Abstract
Introduction Neuroticism is a complex personality trait encompassing diverse aspects. Notably, high levels of neuroticism are related to the onset of psychiatric conditions, including anxiety and mood disorders. Personality traits are stable individual features; therefore, they can be expected to be associated with stable neurobiological features, including the Brain Resting State (RS) activity as measured by fMRI. Several metrics have been used to describe RS properties, yielding rather inconsistent results. This inconsistency could be due to the fact that different metrics portray different RS signal properties and that these properties may be differently affected by neuroticism. To explore the distinct effects of neuroticism, we assessed several distinct metrics portraying different RS properties within the same population. Method Neuroticism was measured in 31 healthy subjects using the Zuckerman-Kuhlman Personality Questionnaire; RS was acquired by high-resolution fMRI. Using linear regression, we examined the modulatory effects of neuroticism on RS activity, as quantified by the Amplitude of low frequency fluctuations (ALFF, fALFF), regional homogeneity (REHO), Hurst Exponent (H), global connectivity (GC) and amygdalae functional connectivity. Results Neuroticism modulated the different metrics across a wide network of brain regions, including emotional regulatory, default mode and visual networks. Except for some similarities in key brain regions for emotional expression and regulation, neuroticism affected different metrics in different ways. Discussion Metrics more related to the measurement of regional intrinsic brain activity (fALFF, ALFF and REHO), or that provide a parsimonious index of integrated and segregated brain activity (HE), were more broadly modulated in regions related to emotions and their regulation. Metrics related to connectivity were modulated across a wider network of areas. Overall, these results show that neuroticism affects distinct aspects of brain resting state activity. More in general, these findings indicate that a multiparametric approach may be required to obtain a more detailed characterization of the neural underpinnings of a given psychological trait. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
50. Alterations of brain activity in fibromyalgia patients.
- Author
-
Sawaddiruk, Passakorn, Paiboonworachat, Sahattaya, Chattipakorn, Nipon, and Chattipakorn, Siriporn C.
- Abstract
Fibromyalgia is a chronic pain syndrome, characterized by widespread musculoskeletal pain with diffuse tenderness at multiple tender points. Despite intense investigations, the pathophysiology of fibromyalgia remains elusive. Evidence shows that it could be due to changes in either the peripheral or central nervous system (CNS). For the CNS changes, alterations in the high brain area of fibromyalgia patients have been investigated but the definite mechanisms are still unclear. Magnetic Resonance Imaging (MRI) and Functional Magnetic Resonance (fMRI) have been used to gather evidence regarding the changes of brain morphologies and activities in fibromyalgia patients. Nevertheless, due to few studies, limited knowledge for alterations in brain activities in fibromyalgia is currently available. In this review, the changes in brain activity in various brain areas obtained from reports in fibromyalgia patients are comprehensively summarized. Changes of the grey matter in multiple regions such as the superior temporal gyrus, posterior thalamus, amygdala, basal ganglia, cerebellum, cingulate cortex, SII, caudate and putamen from the MRI as well as the increase of brain activities in the cerebellum, prefrontal cortex, anterior cingulate cortex, thalamus, somatosensory cortex, insula in fMRI studies are presented and discussed. Moreover, evidence from pharmacological interventions offering benefits for fibromyalgia patients by reducing brain activity is presented. Because of limited knowledge regarding the roles of brain activity alterations in fibromyalgia, this summarized review will encourage more future studies to elucidate the underlying mechanisms involved in the brains of these patients. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.