Coherent analysis in electroencephalography. Experience in the use of coherent analysis in the assessment of disorders of human mental functions in practical electroencephalography. (Lecture three)

Abstract

It is discussed what actually useful coherent analysis can give in solving the problem of assessing the system- functional organization of cortical rhythms, which underlies the clinical interpretation of quantitative indicators of intracerebral connections. The authors emphasized. That in the basis of the assessment of disorders of the mental function of the brain according to EEG data, one should look for signs of dissociation of the level of wakefulness in non-sleeping people. It is necessary to look for features of the electroencephalographic picture, which can be considered as neurophysiological neurotic patterns and, most importantly, an assessment of the state of the systemic- functional organization of the cortical rhythm, interpreted as a state of hypofrontality. The authors took the path of visual illustration using examples of specific patients with various pathological states of brain function. The features of changes in coherence indices in patients with hyperactivity syndrome, in violation of the function of attention, with mental retardation, in vegetative- vascular dystonia are given. The authors cite the observation of a child with sensorineural hearing loss from birth and connect the fact of a decrease in the level of intertemporal relations, not with the underlying disease, but with the lack of oral speech skills. The paper emphasizes that hypersynchronization of the alpha rhythm is quite pathognomonic to the state of increased anxiety. The authors explain in detail under what states of mental dysfunction the values of the average coherence are more informative, and in which the values of the dominant frequency. In conclusion, the authors complain about the unsatisfactory software capabilities of mathematical processing in some EEG computer systems, so neurophysiologists have unequal opportunities.