Frequency and Phase Synchronization in Neuromagnetic Cortical Responses to Flickering-Color Stimuli - Physics > Medical PhysicsReportar como inadecuado




Frequency and Phase Synchronization in Neuromagnetic Cortical Responses to Flickering-Color Stimuli - Physics > Medical Physics - Descarga este documento en PDF. Documentación en PDF para descargar gratis. Disponible también para leer online.

Abstract: In our earlier study dealing with the analysis of neuromagnetic responsesmagnetoencephalograms - MEG to flickering-color stimuli for a group ofcontrol human subjects 9 volunteers and a patient with photosensitiveepilepsy a 12-year old girl, it was shown that Flicker-Noise SpectroscopyFNS was able to identify specific differences in the responses of eachorganism. The high specificity of individual MEG responses manifested itself inthe values of FNS parameters for both chaotic and resonant components of theoriginal signal. The present study applies the FNS cross-correlation functionto the analysis of correlations between the MEG responses simultaneouslymeasured at spatially separated points of the human cortex processing thered-blue flickering color stimulus. It is shown that the cross-correlations forcontrol healthy subjects are characterized by frequency and phasesynchronization at different points of the cortex, with the dynamics ofneuromagnetic responses being determined by the low-frequency processes thatcorrespond to normal physiological rhythms. But for the patient, the frequencyand phase synchronization breaks down, which is associated with the suppressionof cortical regulatory functions when the flickering-color stimulus is applied,and higher frequencies start playing the dominating role. This suggests thatthe disruption of correlations in the MEG responses is the indicator ofpathological changes leading to photosensitive epilepsy, which can be used fordeveloping a method of diagnosing the disease based on the analysis with theFNS cross-correlation function.



Autor: S. F. Timashev, Yu. S. Polyakov, R. M. Yulmetyev, S. A. Demin, O. Yu. Panischev, S. Shimojo, J. Bhattacharya

Fuente: https://arxiv.org/



DESCARGAR PDF




Documentos relacionados