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Background: Spatial and temporal resolution of brain network activity can be improved by combining different modalities. Functional Magnetic Resonance Imaging (fMRI) provides full brain coverage with limited temporal resolution, while electroencephalography (EEG), estimates cortical activity with high temporal resolution. Combining them may provide improved network characterization., New Method: We examined relationships between EEG spatiospectral pattern timecourses and concurrent fMRI BOLD signals using canonical hemodynamic response function (HRF) with its 1 st and 2 nd temporal derivatives in voxel-wise general linear models (GLM). HRF shapes were derived from EEG-fMRI time courses during "resting-state", visual oddball and semantic decision paradigms., Results: The resulting GLM F-maps self-organized into several different large-scale brain networks (LSBNs) often with different timing between EEG and fMRI revealed through differences in GLM-derived HRF shapes (e.g., with a lower time to peak than the canonical HRF). We demonstrate that some EEG spatiospectral patterns (related to concurrent fMRI) are weakly task-modulated., Comparison With Existing Method(s): Previously, we demonstrated 14 independent EEG spatiospectral patterns within this EEG dataset, stable across the resting-state, visual oddball and semantic decision paradigms. Here, we demonstrate that their time courses are significantly correlated with fMRI dynamics organized into LSBN structures. EEG-fMRI derived HRF peak appears earlier than the canonical HRF peak, which suggests limitations when assuming a canonical HRF shape in EEG-fMRI., Conclusions: This is the first study examining EEG-fMRI relationships among independent EEG spatiospectral patterns over different paradigms. The findings highlight the importance of considering different HRF shapes when spatiotemporally characterizing brain networks using EEG and fMRI., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Neuroimaging methods have been used to study differences of brain function between males and females. Differences in working memory have been also investigated, but results of such studies are mixed with respect to behavioral data, reaction times and activated brain areas. We tried to analyze functional MRI data acquired during the working memory task and search for differences of brain activation between genders. 20 healthy right-handed volunteers (10 males and 10 females) participated in the study. All of them were university students or fresh graduates. Subjects underwent block designed verbal working memory task (Item Recognition Task) inside the MRI scanner. Standard single-subject pre-processing and group fMRI analyses were performed using the FEAT software from FSL library. In the behavioral data, there was no statistically significant difference in the number of correct responses during the task. The task activated similar bilateral regions of frontal, parietal, temporal and occipital lobes, basal ganglia, the brainstem and in the cerebellum, which corresponds to the previous verbal working memory neuroimaging research. In direct comparison, there was no statistically significant difference in brain activation between small samples of male and female young healthy volunteers.

Botulinum toxin type A (BoNT) is considered an effective therapeutic option in cervical dystonia (CD). The pathophysiology of CD and other focal dystonias has not yet been fully explained. Results from neurophysiological and imaging studies suggest a significant involvement of the basal ganglia and thalamus, and functional abnormalities in premotor and primary sensorimotor cortical areas are considered a crucial factor in the development of focal dystonias. Twelve BoNT-naïve patients with CD were examined with functional MRI during a skilled hand motor task; the examination was repeated 4 weeks after the first BoNT injection to the dystonic neck muscles. Twelve age- and gender-matched healthy controls were examined using the same functional MRI paradigm without BoNT injection. In BoNT-naïve patients with CD, BoNT treatment was associated with a significant increase of activation in finger movement-induced fMRI activation of several brain areas, especially in the bilateral primary and secondary somatosensory cortex, bilateral superior and inferior parietal lobule, bilateral SMA and premotor cortex, predominantly contralateral primary motor cortex, bilateral anterior cingulate cortex, ipsilateral thalamus, insula, putamen, and in the central part of cerebellum, close to the vermis. The results of the study support observations that the BoNT effect may have a correlate in the central nervous system level, and this effect may not be limited to cortical and subcortical representations of the treated muscles. The results show that abnormalities in sensorimotor activation extend beyond circuits controlling the affected body parts in CD even the first BoNT injection is associated with changes in sensorimotor activation. The differences in activation between patients with CD after treatment and healthy controls at baseline were no longer present.

Background: Cervical spondylotic myelopathy (CSM) is the most common cause of spinal cord dysfunction, potentially leading to severe disability. Abnormal cervical spine magnetic resonance imaging (MRI) and motor evoked potentials (MEPs) are independent predictors of disease progression. Abnormal MRI is accompanied by various activation changes in functional brain MRI (fMRI), whereas preoperative and postoperative fMRI adaptations associated with abnormal preoperative MEP remain unknown., Methods: Twenty patients (9 males, average age 56.6) with evidence of spinal cord compression on MRI and clinical signs of mild CSM were included. Participants were classified according to their preoperative MEP and underwent three brain fMRI examinations: before surgery, 6, and 12 months after surgery while performing repeated extension-flexion of each wrist., Results: Functional MRI activation was compared between two subsets of patients, with normal and clearly abnormal MEP (right wrist: 8 vs. 8; left wrist: 7 vs. 9). At baseline, abnormal MEPs were associated with hyperactivation in the cerebellum. At the first follow-up, further hyperactivations emerged in the contralateral sensorimotor cortices and persisted for 1 year. In normal baseline MEP, activation mostly decreased in the ipsilateral sensorimotor cortex postoperatively. The ipsilateral sensorimotor activation after 1-year follow-up correlated with baseline MEP., Conclusions: Abnormal corticospinal MEP findings in cervical spondylotic myelopathy were associated with differences in brain activation, which further increased after spinal cord decompression and did not resolve within 12-month follow-up. In summary, surgery may come too late for those patients with abnormal MEP to recover completely despite their mild clinical signs and symptoms.

Fifty years ago, when the effect of antidepressants on panic disorder was described, a significant progress in understanding this anxiety disorder has been made. Theoretical mechanisms and models of fear and panic disorder were proposed and tested in animal models and humans. With growing possibilities of non-invasive neuroimaging techniques, there is an increasing amount of information on the panic disorder. Unfortunately, a number of circumstances lead to inconsistent findings and its interpretations. In our review, we focused on functional MRI in panic disorder, limitations of current studies, possible interpretations and proposals for future direction. In our opinion, the current findings support the neuroanatomical model of panic disorder at the level of group data analysis. But at the same time, the results suggest significant inter-individual differences across the patients, which may be related to each patient's individual history, woven into their neural network and affecting the individual symptoms and response to therapy.

Objective: Previous functional brain imaging studies have described various and contradictory activation findings in patients with panic disorder (PD). Our study focused on patients with a chronic PD, who were investigated and treated in a conventional manner, which represents the real PD patients in clinical practice., Methods: Continuing their medication, patients were included in a six-week cognitive-behavioral therapy (CBT) program in the psychiatry department. At the onset of the study, participants underwent clinical evaluation using standard scales and were examined using fMRI while listening to verbal threat-related stimuli contrasted to neutral words. According to the therapeutic outcome, they were subsequently divided into two groups, responders, and nonresponders and the two groups were mutually compared., Results: In non-responders compared to responders, we found increased pre-treatment activation in dorsolateral prefrontal cortex bilaterally, left orbitofrontal cortex, left frontal eye field, right parietal lobule and left amygdala. In addition, both groups showed negative fMRI BOLD correlation with BAI improvement and positive correlation with CGI improvement across the ROIs. We suggest that DLPFC over-activation may reveal a lack of cognitive control over emotional processing, which makes subsequent CBT less effective., Conclusion: Despite several limitations, we found neuroimaging predictors of poor CBT response, under the conditions of standard clinical practice, in real PD patients.

Purpose of the Study: The aim of the study was to measure the sensorimotor brain adaptation activity, shown on functional magnetic resonance images (fMRI), in relation to the degree and extent of spinal cord compression or cervical spondylotic myelopathy (CSM) detected by cervical spine MRI., Material and Methods: Twenty-one patients (average age, 57 years; 9 men and 12 women) with anterior cervical cord compression detected on cervical MRI scans were included. On the images, the degree of spinal canal stenosis, the spinal cord compression based on the antero-posterior diameter of the spinal canal and on transverse areas of the cervical spinal cord and cervical spinal canal, and changes in spinal cord signal intensity were identified. Clinical examination included neurological status, Japanese Orthopaedic Association (JOA) score, Neck Disability Index (NDI) and pain intensity assessment using the Visual Analogue Scale (VAS). Electrophysiological tests involving motor evoked and sensory evoked potential (MEP and SEP) recording were conducted and, using fMRI, brain activity during movement of both arms was measured. Based on the transverse spinal cord area of above or below 70 mm2, the patients were placed into two subgroups. According to changes in spinal cord signal intensity, the patients were included into three subgroups with normal findings, incipient myelopathy and advanced myelopathy, respectively. Surgery was carried out from the anterior approach and involved cervical disc replacement. All examinations were performed again at 6 months after surgery. Pre- and post-operative results were compared within each set of subgroups and statistically evaluated., Results: The average pre-operative values were found to increase post-operatively as follows: from 6.4 mm to 8.9 mm (by 39%) for the antero-posterior diameter of the spinal canal; from 129.3 mm2 to 162.8 mm2 (by 26%) for the transverse area of the spinal canal; from 72.6 mm2 to 87.4 mm2 (by 20%) for the transverse spinal cord area; and from 16.3 to 17.4 for the JOA score. The average NDI decreased from 37.9 to 23.7 and the average VAS fell from 6.4 to 1.5. All patients with the change of spinal cord signal that indicated advanced myelopathy also had relevant pathological findings on MEP/SEP examination and this was statistically significant. There was no significant difference in fMRI scans between the two subgroups established on the basis of transverse spinal cord area measurements. In the patients grouped by a change in spinal cord signals, the pre-operative fMRI showed a significantly higher brain activation volume in the subgroup with advanced myelopathy, as compared with the two other subgroups. Surgery resulted in a moderate reduction of the volume of active brain tissue in all three groups. In the patients with advanced myelopathy evaluated in relation to local changes in brain activation, surgery led to a significant decrease in activation volumes in the ipsilateral primary motor cortex and cerebellar hemisphere. There was also a significant increase in activation of the contralateral supplementary motor cortex., Discussion: It is evident that the brain responds to spinal cord damage by increased activity, but with a certain delay. A slightly altered spinal cord signal intensity, such as in incipient myelopathy, apparently does not result in brain activation. On the other hand, significant changes in signal intensity in advanced myelopathy are related to deterioration of spinal cord function, as shown by MEP and SEP examination results, and an increase in both the volume and intensity of cortical motor activation as a compensation mechanism for myelopathy. CONCLUSIONS Hyperintense spinal cord signals on T2-weighted images correlated with the pathological spinal cord function detected by electrophysiological test in all patients. The transverse spinal cord area (around 70 mm2) showed no significant correlation with either sensory and motor brain adaptations or the results of SEP and MEP testing; therefore, as a criterion for indication to surgery it is of no value. The patients with advanced myelopathy, as detected by spinal cord MRI, had a significantly higher pre-operative cortical motor activation on fMRI than patients with normal findings or those with incipient myelopathy. In addition, the patterns of cortical motor activation altered significantly at 6 months after spinal cord decompression, which was shown by an increase or decrease in activation of the relevant motor cortex areas.

The GAITFAST study (gait recovery in patients after acute ischemic stroke) aims to compare the effects of treadmill-based robot-assisted gait training (RTGT) and therapist-assisted treadmill gait training (TTGT) added to conventional physical therapy in first-ever ischemic stroke patients. GAITFAST (Clinicaltrials.gov identifier: NCT04824482) was designed as a single-blind single-center prospective randomized clinical trial with two parallel groups and a primary endpoint of gait speed recovery up to 6 months after ischemic stroke. A total of 120 eligible and enrolled participants will be randomly allocated (1:1) in TTGT or RTGT. All enrolled patients will undergo a 2-week intensive inpatient rehabilitation including TTGT or RTGT followed by four clinical assessments (at the beginning of inpatient rehabilitation 8–15 days after stroke onset, after 2 weeks, and 3 and 6 months after the first assessment). Every clinical assessment will include the assessment of gait speed and walking dependency, fMRI activation measures, neurological and sensorimotor impairments, and gait biomechanics. In a random selection (1:2) of the 120 enrolled patients, multimodal magnetic resonance imaging (MRI) data will be acquired and analyzed. This study will provide insight into the mechanisms behind poststroke gait behavioral changes resulting from intensive rehabilitation including assisted gait training (RTGT or TTGT) in early subacute IS patients.

Sustained pressure stimulation of the body surface has been used in several physiotherapeutic techniques, such as reflex locomotion therapy. Clinical observations of global motor responses and subsequent motor behavioral changes after stimulation in certain sites suggest modulation of central sensorimotor control, however, the neuroanatomical correlates remain undescribed. We hypothesized that different body sites would specifically influence the sensorimotor system during the stimulation. We tested the hypothesis using functional magnetic resonance imaging (fMRI) in thirty healthy volunteers (mean age 24.2) scanned twice during intermittent manual pressure stimulation, once at the right lateral heel according to reflex locomotion therapy, and once at the right lateral ankle (control site). A flexible modeling approach with finite impulse response basis functions was employed since non-canonical hemodynamic response was expected. Subsequently, a clustering algorithm was used to separate areas with differential timecourses. Stimulation at both sites induced responses throughout the sensorimotor system that could be mostly separated into two anti-correlated subsystems with transient positive or negative signal change and rapid adaptation, although in heel stimulation, insulo-opercular cortices and pons showed sustained activation. In direct voxel-wise comparison, heel stimulation was associated with significantly higher activation levels in the contralateral primary motor cortex and decreased activation in the posterior parietal cortex. Thus, we demonstrate that the manual pressure stimulation affects multiple brain structures involved in motor control and the choice of stimulation site impacts the shape and amplitude of the blood oxygenation level-dependent response. We further discuss the relationship between the affected structures and behavioral changes after reflex locomotion therapy.

Introduction: The aim of our study was the correlation of regional brain activity with intensity of psychopathology and the correlation of treatment effect of CBT in patients suffering from panic disorder. Method: Five patients suffering from panic disorder and five healthy controls were studied in fMRI during the exposition of threat-related words compared with neutral words and emotional faces compared with fixation points. Inpatients were treated with CBT (Cognitive Behavioral Therapy) and existing pharmacotherapy for 6 weeks. Patients were studied in fMRI scanner before and after the treatment. Psychopathology was assessed using Beck Anxiety Inventory (BAI) and Beck Depression Inventory (BDI), The Clinical Global Impression rating scales (CGI), Panic Disorder Severity Scale (PDSS), Dissociative Experiences Scale (DES). Data were analyzed using software for functional magnetic analysis (AFNI) and compared with psychopathology rating scales. Results: Hyperactivity of cerebellum in patient treated with CBT compared with healthy controls was observed after activation by anxiety words and faces. The scores of psychopathology rating scales decreased in patient treated with CBT and correlates with decrease of hyperactivity in cerebellum. Conclusion: Changes of brain activity in fMRI after the CBT treatment were observed in patient suffering from panic disorder. Threat-related words and emotional faces showed cerebellum hyperactivity in patients compared with healthy controls. Decrease of cerebellum hyperactivity was observed after treatment with CBT, compared with healthy controls. Predictor of therapeutic response in fMRI was not find. Cerebellum play an important role in panic disorder. Supported with project IGA NS 10301-3/2009 [ABSTRACT FROM AUTHOR]