A statistical technique for measuring synchronism between cortical regions in the EEG during rhythmic stimulation

de, A.M.F.L. Miranda; Infantosi, Antonio Fernando Catelli; Simpson, David M.

doi:10.1109/10.951526

Cited by 15 publications

(8 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…However, it is clear that they are much less evident than the evoked responses. It has been shown [36] that power analyses are less sensitive in response detection than methods that include phase information such as coherent averaging or coherence, so in the next step the existence of induced activity was investigated using coherence analyses.…”

Section: Discussionmentioning

confidence: 99%

“…The difference between the results coming from the two methods (power and coherence) may imply either that the coherence is a more sensitive method than power analyses (as [36] also claims) for detecting induced activity in the signal or that there is little increase or decrease in the power in beta frequency band but that there is phase synchronisation in the [0.2 0.6] s time range which can be picked up by coherence but not power analyses. It has been repeatedly suggested [44] that evoked responses may be the result of synchronisation of the phase in on-going EEG activity rather than additive neuronal activity.…”

Section: Discussionmentioning

confidence: 99%

“…It has been shown that the evoked response to a rhythmic stimulation is easier to detect with coherence analyses (coherence with the stimulus) rather than power analyses [36,37]. This is tested in the current paper for induced activity and in response to both pure tones and word stimuli.…”

Section: Coherence Analysesmentioning

confidence: 95%

“…This is tested in the current paper for induced activity and in response to both pure tones and word stimuli. Magnitude Squared Coherence (MSC) between two discrete signals x[k] and y[k] is a measure of linear interdependence between two signals and can be calculated from Equation (1) [36]:…”

Section: Coherence Analysesmentioning

confidence: 99%

See 3 more Smart Citations

Induced activity in EEG in response to auditory stimulation

Hosseini

Bell

Wang

et al. 2015

Biomedical Signal Processing and Control

View full text Add to dashboard Cite

The response of the brain to a sensory stimulus may present itself in the electroencephalogram (EEG) as evoked and/or induced activity. While the evoked response is given by peaks and troughs in the signal, time-locked and phase-locked to the stimuli, the induced response is time-but not phase-locked, and can be considered as an increase or a decrease in the power of EEG in a specific frequency band at a specific time range with regard to the stimulus onset. The induced response does not have the same phase following successive stimuli. It is believed that cognition and perception of a stimulus present themselves primarily as the induced response in the EEG. In this paper, the induced response of the brain to auditory speech stimuli is investigated and different approaches to detect induced activity are compared. It is shown that there is an increase in theta and delta power in response to words compared to the baseline, starting around 500 ms after their onset. During this time, there is also an increase in pairwise coherence between the posterior electrodes. In response to tone bursts, a change in pairwise coherence was observed in the beta band starting around 200 ms. To the best of our knowledge, this is the first time such responses have been described using simple protocols without complex stimulus manipulations being involved. Responses in the EEG to speech rather than the more conventional tone-bursts or clicks suggests that it may be feasible to use the EEG as an objective means to demonstrate brain activation to salient real world stimuli. This would be of particular benefit in investigating access to speech in patients who are unable or unwilling to reliably respond to conventional subjective experimental protocols, such as infants.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Coherence Analysesmentioning

confidence: 95%

Section: Coherence Analysesmentioning

confidence: 99%

See 2 more Smart Citations

Induced activity in EEG in response to auditory stimulation

Hosseini

Bell

Wang

et al. 2015

Biomedical Signal Processing and Control

View full text Add to dashboard Cite

show abstract

“…The confidence intervals of r 2 were calculated by using a modified method reported by Miranda de Sá et al 14 . In practice, r 2 values > 0.6 were considered significant.…”

Section: Methodsmentioning

confidence: 99%

Effect of oscillatory breathing on the variability of the RR Intervals and its prognostic importance in individuals with left ventricular global systolic dysfunction

Pr¹,

J²,

Cordovil³

2003

Arq. Bras. Cardiol.

View full text Add to dashboard Cite

In healthy individuals, the duration of RR intervals in tha surface electrocardiogram varies cyclically from beat to beat. This variation is more significant in youngsters, is modulated by breathing movements, and is called respiratory sinus arrhythmia.The characteristics of the breathing movements can alter the cyclic variations observed between successive electrocardiographic R waves (RR intervals). These alterations result both from direct influences on the modulation of the parasympathetic nervous system and the indirect influences of chemoreceptor mechanismsIn approximately 50% of the individuals with left ventricular global systolic dysfunction, the presence of abnormal patterns of breathing can be identified. In these individuals, oscillatory patterns of breathing (oscillatory breathing) can be observed both during sleep and during wakefulness, and are characterized by successive periods of tachy/hyperpnea followed by brady/hypopnea, and, eventually, apnea [2][3][4][5][6][7][8][9][10] . Of the types of oscillatory breathing of clinical significance, Cheyne-Stokes respiration and periodic breathing stand out. Cheyne-Stokes respiration is the breathing pattern in which periods of tachy/hyperpnea are followed by regular periods of apnea. In periodic breathing, however, the periods of tachy/hyperpnea are cyclically followed by periods of brady/hypopnea with no apnea.Although some authors have reported that oscillatory breathing, especially when observed during wakefulness, may be associated with more severe clinical findings and a more reserved prognosis 2,6-8 , the subject remains controversial.This study aimed at analyzing the effects of oscillatory breathing on the behavior of the cyclic variations of the normal electrocardiographic RR intervals (V-RR) during wakefulness in individuals with left ventricular global systolic dysfunction and in sinus rhythm, and at assessing the influence of oscillatory breathing on clinical and laboratory findings, and on the mortality rate of the individuals studied. Objective -To assess the effect of the oscillatory breathing on the variability of RR intervals (V-RR) and on prognostic significance after one year follow-up in subjects with left ventricular global systolic dysfunction. Methods -We studied 76 subjects, whose age ranged from 40 to 80 years, paired for age and gender, divided into two groups: group I -34 healthy subjects; group II -42 subjects with left ventricular global systolic dysfunction (ejection fraction ≤ 0.40). The ECG signals were acquired during 600s in supine position, and analyzed the variation of the thoracic amplitude and the V-RR. Clinical and V-RR variables were applied into a logistic multivariate model to foretell survival after one year follow-up. Results -

show abstract