scholarly journals Development of TMS Trigger System for Suppressing MEP Fluctuation Using EEG Coherence Analysis: Algorithm Development and Validation Study (Preprint)

2021 ◽  
Author(s):  
Keisuke Sasaki ◽  
Yuki Fujishige ◽  
Yutaka Kikuchi ◽  
Masato Odagaki
Keyword(s):  
Frequency Domain ◽  
Coefficient Of Variation ◽  
Primary Motor Cortex ◽  
Motor Evoked Potential ◽  
Coherence Analysis ◽  
Eeg Coherence ◽  
Trigger System ◽  
F Test ◽  
Experimental Time ◽  
Significant Difference

BACKGROUND Transcranial magnetic stimulation (TMS), when applied over the primary motor cortex (M1) elicits a motor evoked potential (MEP) in electromyograms measured from peripheral muscles. MEP amplitude has often been observed to fluctuate trial by trial, even with a constant stimulus. Many factors cause MEP fluctuations in TMS. One of the primary factors is the weak stationarity and instability of cortical activity in the brain, from which we assumed MEP fluctuations originated. We hypothesized that MEP fluctuations must be suppressed if TMS is delivered to M1 at the time when several electroencephalogram (EEG) channels measured on the scalp have high similarity in the frequency domain. OBJECTIVE We developed a TMS triggering system for suppressing MEP fluctuations using EEG coherence analysis, which was performed to detect the EEG signal similarity between the two channels in the frequency domain. METHODS Seven healthy adults participated in the experiment to confirm whether the TMS trigger system works adequately, and the mean amplitude and coefficient of variation of the MEP were recorded and compared with the values in the control task. We also determined the experimental time under each condition and verified whether it was within the predicted time. RESULTS The coefficient of variation (CV) of MEP amplitude decreased in five out of seven subjects, and significant differences (P=.02) were confirmed in two of the subjects by performing an F-test. The CV of the experimental time required for each stimulus with threshold modification was less than that without threshold modification, and a significant difference (P<.001) was confirmed by performing an F-test. CONCLUSIONS We consequently found that MEP could be suppressed using the system developed in this study and that the TMS trigger system could also stabilize the experimental time by changing the triggering threshold automatically.

scholarly journals EEG Coherence Analysis for Suppression of MEP Amplitude Variability in TMS

2021 ◽  
Vol 17 (06) ◽  
pp. 87
Author(s):  
Keisuke Sasaki ◽  
Yuki Fujishige ◽  
Masato Odagaki
Keyword(s):  
Cortical Neurons ◽  
Primary Motor Cortex ◽  
Cortical Excitability ◽  
Motor Evoked Potentials ◽  
Motor Evoked Potential ◽  
Coherence Analysis ◽  
Eeg Coherence ◽  
Peripheral Muscle ◽  
Online Measurements ◽  
Stimulation Method

Transcranial magnetic stimulation (TMS) is a non-invasive stimulation method for cortical neurons. When TMS is delivered to the primary motor cortex (M1), motor evoked potentials can be measured in electromyograms for the peripheral muscle. However, the motor-evoked potential (MEP) amplitudes measured by stimulations for M1 fluctuated from trial to trial. MEP fluctuations are caused by changes in cortical excitability. We hypothesized that MEP variability could be suppressed with application of TMS when cortical excitability was stable. Thus, we developed a TMS system to suppress MEP amplitude variabilities. We used electroencephalographic (EEG) online measurements with coherence analysis to obtain the similarity of cortical excitabilities. The system enables us to trigger TMS if the EEGs measured from the two channels have a high similarity in the frequency domain. In this study, we found that the suppression of MEP fluctuation was dependent on the state of cortical excitability obtained by EEG coherence analysis.

Reduced cortical excitability in depression

1999 ◽  
Vol 174 (5) ◽  
pp. 449-454 ◽  
Author(s):  
P. M. Shajahan ◽  
M. F. Glabus ◽  
P. A. Gooding ◽  
P. J. Shah ◽  
K. P. Ebmeier
Keyword(s):  
Magnetic Stimulation ◽  
Evoked Potential ◽  
Primary Motor Cortex ◽  
Cortical Excitability ◽  
Motor Evoked Potential ◽  
Abductor Pollicis Brevis ◽  
Post Exercise ◽  
Significant Difference ◽  
Dsm Iv ◽  
The Mean

BackgroundIn healthy controls, preactivation of muscles by exercise results in enhanced motor-evoked potential (MEP) responses to transcranial magnetic stimulation (TMS).AimsWe tested the hypothesis that medicated, depressed patients would show reduced post-exercise MEP facilitation compared with controls.MethodTen patients with DSM-IV depression (two male, eight female) and ten controls (three male, seven female) participated. MEPs were elicited at rest, then after exercising the contralateral abductor pollicis brevis muscle, using TMS of the primary motor cortex.ResultsThe mean MEP amplitude recorded after exercise (expressed as a percentage of baseline) was 210% in controls and 130% in patients. There was a significant difference in post-exercise MEP between patients and controls (P=0.03).ConclusionsPost-exercise MEP facilitation was demonstrated in controls but not in patients. This supports the hypothesis that the modulation of cortical excitability may be impaired in depression.

scholarly journals Demand on skillfulness modulates interhemispheric inhibition of motor cortices

2016 ◽  
Vol 115 (6) ◽  
pp. 2803-2813 ◽  
Author(s):  
Miles Wischnewski ◽  
Greg M. Kowalski ◽  
Farrah Rink ◽  
Samir R. Belagaje ◽  
Marc W. Haut ◽  
...  
Keyword(s):  
Primary Motor Cortex ◽  
Motor Task ◽  
Conditioning Stimulus ◽  
Motor Evoked Potential ◽  
Inhibitory Effect ◽  
Left Hand ◽  
The Mean ◽  
Small Targets ◽  
Healthy Participants

The role of primary motor cortex (M1) in the control of hand movements is still unclear. Functional magnetic resonance imaging (fMRI) studies of unimanual performance reported a relationship between level of precision of a motor task and additional ipsilateral M1 (iM1) activation. In the present study, we determined whether the demand on accuracy of a movement influences the magnitude of the inhibitory effect between primary motor cortices (IHI). We used transcranial magnetic stimulation (TMS) to measure active IHI (aIHI) of the iM1 on the contralateral M1 (cM1) in the premovement period of a left-hand motor task. Ten healthy participants manipulated a joystick to point to targets of two different sizes. For aIHI, the conditioning stimulus (CS) was applied to iM1, and the test stimulus (TS) to cM1, with an interstimulus interval of 10 ms. The amount of the inhibitory effect of the CS on the motor-evoked potential (MEP) of the subsequent TS was expressed as percentage of the mean MEP amplitude evoked by the single TS. Across different time points of aIHI measurements in the premovement period, there was a significant effect for target size on aIHI. Preparing to point to small targets was associated with weaker aIHI compared with pointing to large targets. The present findings suggest that, during the premovement period, aIHI from iM1 on cM1 is modulated by the demand on accuracy of the motor task. This is consistent with task fMRI findings showing bilateral M1 activation during high-precision movements but only unilateral M1 activity during low-precision movements.

scholarly journals Detect AD Patients by Using EEG Coherence Analysis

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Ming-Chung Ho ◽  
Tsung-Ching Chen ◽  
Chin-Fei Huang ◽  
Cheng-Hsieh Yu ◽  
Jhih-Ming Chen ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Healthy Subjects ◽  
Normal Aging ◽  
Oddball Paradigm ◽  
Coherence Analysis ◽  
Eeg Coherence ◽  
Theta Band ◽  
Corticocortical Connections ◽  
Auditory Oddball ◽  
Auditory Oddball Paradigm

The purpose of this study is to discriminate mild Alzheimer’s disease (AD) patients from the normal aging. The EEG coherence was applied to analyze the data from auditory oddball paradigm to discriminate the differences of corticocortical connections between mild AD patients and healthy subjects. The results showed that the lower values of coherence were performed in mild AD patients than in the normal aging subjects, especially in theta band. The implications and suggestions are shown in this study.

scholarly journals Comparison of tibialis anterior and gastrocnemius muscles activation on balance training devices and hoverboard

2017 ◽  
Vol 13 (4-2) ◽  
pp. 495-500 ◽  
Author(s):  
Khairiyah Abdul Rahman ◽  
Aizreena Azaman ◽  
Hadafi Fitri Mohd Latip ◽  
Mohd Azuwan Mat Dzahir ◽  
Malarvili Balakrishnan
Keyword(s):  
Frequency Domain ◽  
Time Domain ◽  
Tibialis Anterior ◽  
Gastrocnemius Muscle ◽  
Balance Training ◽  
Domain Analysis ◽  
Median Frequency ◽  
Training Device ◽  
Emg Signal ◽  
Significant Difference

Balance training devices such as wobble board, basu ball and balance cushion are the tool use in balance training exercise programme in order to improve muscle strength and restore posture balance due degeneration of body function or injury. Recently, self-balancing scooter such as Segway and hover board showed a positive effects on rehabilitation. However, it is less known how these devices affect muscle physiological properties. This study aims to to measure ankle muscles activation on  difference balance training devices and hover board. Besides, a comparison between these device will be done in order to identify if hover board has a promising feature to be an alternative balance training device. In this research, surface EMG (sEMG) was used to record tibialis anterior and gastrocnemius muscle activities. Seventeen healthy subjects were required to stand on three different types of balance training device such as wobble board, balance cushion, bosu ball and a hover board. They were asked to maintain their standing position on each devices for two minutes. Both time domain and frequency domain analysis were used to identify the features of the EMG signal. Time domain analysis measurement involved average rectified value (ARV) and root mean square (RMS), meanwhile for frequency domain, median frequency (MDF) of the signal were measured. The results shows that, the RMS is differed significantly between the balance training devices (p<0.05) for tibialis anterior muscle but not gastrocnemius muscle. Meanwhile, no significant difference between the devices in the ARV and the MDF value (p>0.05). Besides, less stable devices increased muscle activity were observed. There is not much difference between hover board and the other devices in term of physiological effects of both tibialis anterior and gastrochemious muscle. It is also suggested that hover board offers a promising feature to be an alternative device for balance training device.

scholarly journals The state of response of autonomic nervous system in children with mitral valve prolapse

2021 ◽  
Vol 26 (4) ◽  
pp. 74-80
Author(s):  
І.О.  Mitiuriaeva-Korniyko ◽  
O.V. Kuleshov ◽  
Ya.A. Medrazhevska ◽  
L.O. Fik ◽  
T.D. Klets
Keyword(s):  
Heart Rate ◽  
Nervous System ◽  
Autonomic Nervous System ◽  
Mitral Valve ◽  
Frequency Domain ◽  
Mitral Valve Prolapse ◽  
Low Frequency ◽  
Very Low Frequency ◽  
Autonomic Nervous ◽  
Significant Difference

The article presents summarized materials on connective tissue dysplasia of the heart, primary mitral valve prolapse, dysfunction of the autonomic system. Aim of research: to estimate the condition of autonomic nervous system in children with primary mitral valve prolapse. We examined 106 children with mitral valve prolapse aged from 13 to 17 years old on the clinical base of city hospital “Center of mother and child” in Vinnitsya. Research included time and frequency domain (evaluation with cardiointervalography. Final results were compared with the control group records. The results showed no statistical significance among time domain parameters in the main group of children. All these indices displayed tendency to sympathetic and parasympathetic autonomic nervous system tonus increase in boys. However, sympathicotonia tendency was noted in girls only. Frequency domain parameters showed similar results, compared with the previous. Nevertheless, very low frequency parameters had statistically significant difference in both subgroups of patience with mitral valve prolapse, including males (3205.8±190.9 against 1717±154, р<0.05) and females (3280±220.1 against 1433±811, р<0.05). There were no statistically significant difference among other frequency domain parameters. Conclusions: we estimated that children with mitral valve prolapse have imbalanced autonomic homeostasis manifested by tone disturbances of both autonomic vegetative system branches with sympathetic predominance. Patients with primary mitral valve prolapse generally have increased sympathetic tone - both boys and girls - according to spectral analysis of heart rate variability indices, heart rate oscillation power of a very low frequency in particular (p<0.05). In children with mitral valve prolapse, the tone of parasympathetic nervous system is generally normal; there is a tendency to its increase in boys and decrease in girls. These children should be under close medical supervision by pediatricians and cardiologists.

scholarly journals Curiosity among School going Students

2015 ◽  
Vol 2 (3) ◽  
Author(s):  
Dr. Shashi Kala Singh
Keyword(s):  
Economic Status ◽  
Rural Students ◽  
Place Of Residence ◽  
F Test ◽  
Socio Economic Status ◽  
Significant Difference ◽  
Test Result

Aim of the present research was to find out the curiosity among school going students as related to gender, socio-economic status and place of residence. Participants were 200 children (100 boys and 100 girls) from different schools of Ranchi town. The scale used was Children’s Curiosity Scale developed by Kumar (1992). Data were analysis by F test. Result showed that there was no significant difference between boys and girls students on curiosity. There was significant difference between curiosities of high and low socio-economic status students. There was no significant difference between urban and rural students.

Coherence analysis of EEG changes during odour stimulation in humans

1996 ◽  
Vol 110 (7) ◽  
pp. 652-656 ◽  
Author(s):  
Hirofumi Harada ◽  
Kimio Shiraishi ◽  
Toshihiko Kato ◽  
Toyoji Soda
Keyword(s):  
Broad Band ◽  
Frontal Region ◽  
Coherence Analysis ◽  
Temporal Region ◽  
Eeg Coherence ◽  
Frequency Bands ◽  
Delta Band ◽  
Eeg Changes ◽  
Eeg Recordings ◽  
And Control

AbstractIn a pilot study, EEG changes during odour administration were evaluated by coherence analysis. Ten normal adults were studied. Simultaneous recordings of 16 EEG channels with, and without, odour administration were stored on magnetic tape for further processing. EEG signals were analysed using a signal analyser. Coherence spectra were calculated between all possible channel pairs on the scalp. The amount of data was reduced by extracting broad band coherence values for five frequency bands: delta (2–3.9 Hz), theta (4–7.9 Hz), alpha 1 (8–9.9 Hz), alpha 2 (10–12.9 Hz), and beta 1 (13–17.9 Hz). Coherence values extracted from the control EEG recordings and those during odour administration were compared to evaluate the presence of any significant differences.The results demonstrated significant changes in the EEG coherence between the two control recordings (control before and control after) in the theta and beta 1 bands. These frequency bands were therefore excluded from the examination. During odorant stimulation with methyl-cyclopentenolone, the coherence in the delta band decreased in the frontal region, while that in the alpha 1 and alpha 2 bands increased in the temporal region. During odorant stimulation with scatol, the coherence in the delta band decreased in the frontal region, while that in the alpha 1 and alpha 2 bands increased between the longitudinal electrode locations. It was suggested that EEG coherence mapping may provide the basis for the development of an objective test of olfactory function in humans.

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