scholarly journals FEATURES OF SENSORIMOTOR DISTURBANCES IN DIFFERENT PERIODS AFTER ISCHEMIC STROKE

2017 ◽  
Vol 8 (2) ◽  
pp. 42-48
Author(s):  
E V Ekusheva ◽  
E S Kiparisova ◽  
E V Shirshova
Keyword(s):  
Ischemic Stroke ◽  
Transcranial Magnetic Stimulation ◽  
Magnetic Stimulation ◽  
Cerebral Hemispheres ◽  
Recovery Processes ◽  
Time Periods ◽  
Sensorimotor Disturbances ◽  
Late Recovery ◽  
The Right ◽  
Degrees Of Severity

The aim of the study was to investigate the clinical and neurophysiological features of sensorimotor disturbances in patients at different time periods after ischemic stroke. Methods. The study involved 133 patients with ischemic stroke in the right and left cerebral hemispheres in the late recovery (58) and residual (75) periods. There were 35 controls. Were performed transcranial magnetic stimulation, evoked abdominal reflexes and somatosensory evoked potentials. Results. It was shown that functional recovery processes are continuing with varying degrees of severity in patients and in a year after stroke. Conclusions. Persistence and severity of sensorimotor disturbances, as well as compensatory opportunities, defined afferent component of poststroke deficit, which implies an additional impact in this area to expand the possibilities of neurorehabilitation in patients after stroke.

The analysis of sensomotor disorders in late recovery and residual periods after ischemic stroke

2016 ◽  
Vol 22 (4) ◽  
pp. 184-189
Author(s):  
Igor’ V. Damulin ◽  
E. V Ekusheva
Keyword(s):  
Ischemic Stroke ◽  
Magnetic Stimulation ◽  
Right Hemisphere ◽  
Term Effect ◽  
Functional Rehabilitation ◽  
Long Term Effect ◽  
Time Periods ◽  
Late Recovery ◽  
One Year

The study was carried out to investigate clinical and neuro-physiological characteristics of sensomotor disorders in patients at different time periods after hemispheric ischemic stroke. The sampling of 133 patients with ischemic stroke in right hemisphere and left hemisphere were examined in late recovering and residual period (58 and 75 patients accordingly). The trans-cranial magnetic stimulation, abdominal reflexes and sensomotor induced potentials were implemented. It is demonstrated that in patients even in one year after stroke processes of functional rehabilitation of various degree of expression continue to be present. The constancy and degree of manifestation of sensomotor disorders and compensatory possibilities as well are determined by afferent component of post-stroke deficiency that supposes long-term effect for broadening possibilities of neuro-rehabilitation of patients after stroke.

Effect of Transcranial Magnetic Stimulation on Bimanual Movements

2005 ◽  
Vol 93 (1) ◽  
pp. 53-63 ◽  
Author(s):  
Jen-Tse Chen ◽  
Yung-Yang Lin ◽  
Din-E Shan ◽  
Zin-An Wu ◽  
Mark Hallett ◽  
...  
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
Motor Cortex ◽  
Left Hemisphere ◽  
Magnetic Stimulation ◽  
Normal Subjects ◽  
Left Index Finger ◽  
Rhythmic Movements ◽  
Bimanual Movements ◽  
Ipsilateral Stimulation ◽  
The Right

Transcranial magnetic stimulation (TMS) of the motor cortex can interrupt voluntary contralateral rhythmic limb movements. Using the method of “resetting index” (RI), our study investigated the TMS effect on different types of bimanual movements. Six normal subjects participated. For unimanual movement, each subject tapped either the right or left index finger at a comfortable rate. For bimanual movement, index fingers of both hands tapped in the same (in-phase) direction or in the opposite (antiphase) direction. TMS was applied to each hemisphere separately at various intensities from 0.5 to 1.5 times motor threshold (MT). TMS interruption of rhythm was quantified by RI. For the unimanual movements, TMS disrupted both contralateral and ipsilateral rhythmic hand movements, although the effect was much less in the ipsilateral hand. For the bimanual in-phase task, TMS could simultaneously reset the rhythmic movements of both hands, but the effect on the contralateral hand was less and the effect on the ipsilateral hand was more compared with the unimanual tasks. Similar effects were seen from right and left hemisphere stimulation. TMS had little effect on the bimanual antiphase task. The equal effect of right and left hemisphere stimulation indicates that neither motor cortex is dominant for simple bimanual in-phase movement. The smaller influence of contralateral stimulation and the greater effect of ipsilateral stimulation during bimanual in-phase movement compared with unimanual movement suggest hemispheric coupling. The antiphase movements were resistant to TMS disruption, and this suggests that control of rhythm differs in the 2 tasks. TMS produced a transient asynchrony of movements on the 2 sides, indicating that both motor cortices might be downstream of the clocking command or that the clocking is a consequence of the 2 hemispheres communicating equally with each other.

scholarly journals Single-Pulse Transcranial Magnetic Stimulation-Evoked Potential Amplitudes and Latencies in the Motor and Dorsolateral Prefrontal Cortex among Young, Older Healthy Participants, and Schizophrenia Patients

2021 ◽  
Vol 11 (1) ◽  
pp. 54
Author(s):  
Yoshihiro Noda ◽  
Mera S. Barr ◽  
Reza Zomorrodi ◽  
Robin F. H. Cash ◽  
Pantelis Lioumis ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Transcranial Magnetic Stimulation ◽  
Magnetic Stimulation ◽  
Dorsolateral Prefrontal Cortex ◽  
Evoked Potential ◽  
Single Pulse ◽  
Signal Propagation ◽  
Lower Amplitude ◽  
Dorsolateral Prefrontal ◽  
The Right

Background: The combination of transcranial magnetic stimulation (TMS) with electroencephalography (EEG) allows for non-invasive investigation of cortical response and connectivity in human cortex. This study aimed to examine the amplitudes and latencies of each TMS-evoked potential (TEP) component induced by single-pulse TMS (spTMS) to the left motor (M1) and dorsolateral prefrontal cortex (DLPFC) among healthy young participants (YNG), older participants (OLD), and patients with schizophrenia (SCZ). Methods: We compared the spatiotemporal characteristics of TEPs induced by spTMS among the groups. Results: Compared to YNG, M1-spTMS induced lower amplitudes of N45 and P180 in OLD and a lower amplitude of P180 in SCZ, whereas the DLPFC-spTMS induced a lower N45 in OLD. Further, OLD demonstrated latency delays in P60 after M1-spTMS and in N45-P60 over the right central region after left DLPFC-spTMS, whereas SCZ demonstrated latency delays in N45-P60 over the midline and right central regions after DLPFC-spTMS. Conclusions: These findings suggest that inhibitory and excitatory mechanisms mediating TEPs may be altered in OLD and SCZ. The amplitude and latency changes of TEPs with spTMS may reflect underlying neurophysiological changes in OLD and SCZ, respectively. The spTMS administered to M1 and the DLPFC can probe cortical functions by examining TEPs. Thus, TMS-EEG can be used to study changes in cortical connectivity and signal propagation from healthy to pathological brains.

scholarly journals Causal modulation of right hemisphere fronto-parietal phase synchrony with Transcranial Magnetic Stimulation during a conscious visual detection task

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Chloé Stengel ◽  
Marine Vernet ◽  
Julià L. Amengual ◽  
Antoni Valero-Cabré
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
Visual Perception ◽  
Frequency Band ◽  
Magnetic Stimulation ◽  
Visual Detection ◽  
Detection Task ◽  
Oscillatory Activity ◽  
Top Down ◽  
The Right ◽  
High Beta

AbstractCorrelational evidence in non-human primates has reported increases of fronto-parietal high-beta (22–30 Hz) synchrony during the top-down allocation of visuo-spatial attention. But may inter-regional synchronization at this specific frequency band provide a causal mechanism by which top-down attentional processes facilitate conscious visual perception? To address this question, we analyzed electroencephalographic (EEG) signals from a group of healthy participants who performed a conscious visual detection task while we delivered brief (4 pulses) rhythmic (30 Hz) or random bursts of Transcranial Magnetic Stimulation (TMS) to the right Frontal Eye Field (FEF) prior to the onset of a lateralized target. We report increases of inter-regional synchronization in the high-beta band (25–35 Hz) between the electrode closest to the stimulated region (the right FEF) and right parietal EEG leads, and increases of local inter-trial coherence within the same frequency band over bilateral parietal EEG contacts, both driven by rhythmic but not random TMS patterns. Such increases were accompained by improvements of conscious visual sensitivity for left visual targets in the rhythmic but not the random TMS condition. These outcomes suggest that high-beta inter-regional synchrony can be modulated non-invasively and that high-beta oscillatory activity across the right dorsal fronto-parietal network may contribute to the facilitation of conscious visual perception. Our work supports future applications of non-invasive brain stimulation to restore impaired visually-guided behaviors by operating on top-down attentional modulatory mechanisms.

Low frequency transcranial magnetic stimulation in subacute ischemic stroke: Number of sessions that altered cortical excitability

2020 ◽  
Vol 47 (4) ◽  
pp. 427-434
Author(s):  
Mohammed S. El-Tamawy ◽  
Moshera H. Darwish ◽  
Saly H. Elkholy ◽  
Engy BadrEldin S. Moustafa ◽  
Shimaa T. Abulkassem ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Transcranial Magnetic Stimulation ◽  
Physical Therapy ◽  
Upper Limb ◽  
Magnetic Stimulation ◽  
Cortical Excitability ◽  
Low Frequency ◽  
Cortical Reorganization ◽  
Therapy Program ◽  
Physical Therapy Program

BACKGROUND: Cortical reorganization between both cerebral hemispheres plays an important role in regaining the affected upper extremity motor function post-stroke. OBJECTIVES: The purpose of the current study was to investigate the recommended number of contra-lesion low frequency repetitive transcranial magnetic stimulation (LF-rTMS) sessions that could enhance cortical reorganization post-stroke. METHODS: Forty patients with right hemiparetic subacute ischemic stroke with an age range between 50–65 yrs were randomly assigned into two equal groups: control (GA) and study (GB) groups. Both groups were treated with a selected physical therapy program for the upper limb. Sham and real contra-lesion LF-rTMS was conducted for both groups daily for two consecutive weeks. Sequential changes of cortical excitability were calculated by the end of each session. RESULTS: The significant enhancement in the cortical excitability was observed at the fourth session in favor of the study group (GB). Sequential rate of change in cortical excitability was significant for the first eight sessions. From the ninth session onwards, no difference could be detected between groups. CONCLUSION: The pattern of recovery after stroke is extensive and not all factors could be controlled. Application of LF-rTMS in conjugation with a selected physical therapy program for the upper limb from four to eight sessions seems to be efficient.

scholarly journals Repetitive Transcranial Magnetic Stimulation (rTMS) to Treat Social Anxiety Disorder: Case Reports and a Review of the Literature

2013 ◽  
Vol 9 (1) ◽  
pp. 180-188 ◽  
Author(s):  
Flávia Paes ◽  
Tathiana Baczynski ◽  
Felipe Novaes ◽  
Tamires Marinho ◽  
Oscar Arias-Carrión ◽  
...  
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
Anxiety Disorder ◽  
Social Anxiety ◽  
Anxiety Disorders ◽  
Social Anxiety Disorder ◽  
Magnetic Stimulation ◽  
Repetitive Transcranial Magnetic Stimulation ◽  
Case Reports ◽  
Therapeutic Option ◽  
The Right

Objectives: Social anxiety disorder (SAD) is a common and debilitating anxiety disorders. However, few studies had been dedicated to the neurobiology underlying SAD until the last decade. Rates of non-responders to standard methods of treatment remain unsatisfactorily high of approximately 25%, including SAD. Advances in our understanding of SAD could lead to new treatment strategies. A potential non invasive therapeutic option is repetitive transcranial magnetic stimulation (rTMS). Thus, we reported two cases of SAD treated with rTMS Methods: The bibliographical search used Pubmed/Medline, ISI Web of Knowledge and Scielo databases. The terms chosen for the search were: anxiety disorders, neuroimaging, repetitive transcranial magnetic stimulation. Results: In most of the studies conducted on anxiety disorders, except SAD, the right prefrontal cortex (PFC), more specifically dorsolateral PFC was stimulated, with marked results when applying high-rTMS compared with studies stimulating the opposite side. However, according to the “valence hypothesis”, anxiety disorders might be characterized by an interhemispheric imbalance associated with increased right-hemispheric activity. With regard to the two cases treated with rTMS, we found a decrease in BDI, BAI and LSAS scores from baseline to follow-up. Conclusion: We hypothesize that the application of low-rTMS over the right medial PFC (mPFC; the main structure involved in SAD circuitry) combined with high-rTMS over the left mPFC, for at least 4 weeks on consecutive weekdays, may induce a balance in brain activity, opening an attractive therapeutic option for the treatment of SAD.

scholarly journals Response preparation involves a release of intracortical inhibition in task-irrelevant muscles

2020 ◽  
Author(s):  
Isaac N. Gomez ◽  
Kara Ormiston ◽  
Ian Greenhouse
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
Magnetic Stimulation ◽  
Index Finger ◽  
Intracortical Inhibition ◽  
Left Index Finger ◽  
Task Condition ◽  
Response Preparation ◽  
Action Preparation ◽  
The Right ◽  
Task Irrelevant

AbstractAction preparation involves widespread modulation of motor system excitability, but the precise mechanisms are unknown. In this study, we investigated whether intracortical inhibition changes in task-irrelevant muscle representations during action preparation. We used transcranial magnetic stimulation (TMS) combined with electromyography in healthy human adults to measure motor evoked potentials (MEPs) and cortical silent periods (CSPs) in task-irrelevant muscles during the preparatory period of simple delayed response tasks. In Experiment 1, participants responded with the left-index finger in one task condition and the right-index finger in another task condition, while MEPs and CSPs were measured from the contralateral non-responding and tonically contracted index finger. During Experiment 2, participants responded with the right pinky finger while MEPs and CSPs were measured from the tonically contracted left-index finger. In both experiments, MEPs and CSPs were compared between the task preparatory period and a resting intertrial baseline. The CSP duration during response preparation decreased from baseline in every case. A laterality difference was also observed in Experiment 1, with a greater CSP reduction during the preparation of left finger responses compared to right finger responses. MEP amplitudes showed no modulation during movement preparation in any of the three response conditions. These findings indicate cortical inhibition associated with task-irrelevant muscles is transiently released during action preparation and implicate a novel mechanism for the controlled and coordinated release of motor cortex inhibition.New & NoteworthyIn this study we observed the first evidence of a release of intracortical inhibition in task-irrelevant muscle representations during response preparation. We applied transcranial magnetic stimulation to elicit cortical silent periods in task-irrelevant muscles during response preparation and observed a consistent decrease in the silent period duration relative to a resting baseline. These findings address the question of whether cortical mechanisms underlie widespread modulation in motor excitability during response preparation.

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