Functional characteristics of the brain and cognitive functions in patients with autonomic dysfunction combined with clinically apparent asthenia

Abstract

Twenty six patients with autonomic dysfunction combined withclinically apparent asthenia and 22 healthy control subjects wereexamined with the use of clinico-neurologic, psychometric, neuropsychologicaland neurophysiological methods of investigation.Electrophysiologically, compression spectral analysis of EEG andauditory event-related potentials Р300 were used. The patients differedsignificantly from controls by the reduced attention selectivity,stability and switching, as well as by depression of short-termmemory on words and digits. The patients group was also characterizedby significantly lower Р300 wave amplitude and spectralpower of EEG alpha band in the occipital areas of both hemispheres,in the posterior frontal, the central and the parietal areas ofthe right hemisphere, as well as by significantly higher spectralpower of EEG theta band in the right frontal, the left parietal andthe central areas of both hemispheres. One may conclude hatchanges of spontaneous and evoked electrical activity of the brain inpatients with an asthenia reflect the decrease in general level of brainfunctional activity owing to abnormal adjusting influences of thelimbic-reticular structures. In this case a sufficient flow of corticalactivation, necessary for the optimal information processing andmaintenance of an adequate level of the directed attention andshort-term memory, can not be generated.

Keywords

• autonomic dysfunction
• asthenia
• limbic-reticular brain structures
• eeg
• auditory event-related potential р300