Improvement of the night sleep quality by electrocutaneous subthreshold stimulation synchronized with the slow wave sleep.

Changes in sleep characteristics were studied under the non-wake-up stimulation with current pulses of less than 1 µA on average, applied to the palmar surface skin receptors during Δ-sleep. A significant increase in duration of the first and second cycles of deep sleep has been found, as well as a shorter latent period before the Δ-sleep onset and a longer time of the rapid sleep (REM phase). The sleep structure improvement was accompanied by the reduced reactive anxiety and depression and an increase in subjective physical efficiency.

[Low-frequency rhythmic electrocutaneous stimulation during slow-wave sleep: physiological and therapeutic effects].

Neocortical EEG slow wave activity (SWA) in the delta frequency band (0.5-4.0 Hz) is a hallmark of slow wave sleep (SWS) and its power is a function of prior wake duration and an indicator of a sleep need. SWS is considered the most important stage for realization of recovery functions of sleep. Possibility of impact on characteristics of a night sleep by rhythmic (0.8-1.2 Hz) subthreshold electrocutaneous stimulation of a hand during SWS is shown: 1st night--adaptation, 2nd night--control, 3d and 4th nights--with stimulation during SWA stages ofa SWS. Stimulation caused significant increase in average duration of SWS and EEG SWA power (in 11 of 16 subjects), and also well-being and mood improvement in subjects with lowered emotional tone. It is supposed that the received result is caused by functioning of a hypothetical mechanism directed on maintenance and deepening of SWS and counteracting activating, awakening influences of the afferent stimulation. The results can be of value both for understanding the physiological mechanisms of sleep homeostasis and for development of non-pharmacological therapy of sleep disorders.

[A new method of monitoring the psycho-emotional condition in patients during balanced anesthesia based on regional blockades]. / Novyi metod monitoringa psikhoémotsional'nogo sostoianiia patsientov vo vremia sbalansirovannoi anestezii na osnove regionarnykh blokad.

The potentialities of a skin-galvanic reaction (SGR) were studied, to evaluate the psycho-emotional status, in 9 sedated (midazole, thiopental-sodium, propofol) classes I and II ASA patients operated (10 interventions) under regional block. An original software was designed to analyze the SGR; it detects the signs of psycho-emotional discomfort (including positional discomfort) in drug-induced depression of consciousness as well as the uncontrollable moments of falling-asleep and awakening.

Automatic checkout systems to monitor driver's vigilance.

A concept for designing automatic checkout systems to prevent drivers from falling asleep is presented. It is shown that such systems should use the frequency of electrodermal reactions (EDR), which is governed by changes in skin resistance. Such changes have a time constant of several seconds. To detect these reactions, a special technique was developed. Experimental investigations yielded the quantitative characteristics of EDR changes associated with decreased vigilance. It was found that, when a person started to fall asleep, the EDR frequency diminished. An EDR-based system was developed to assess the alertness level. Such a system may be employed to prevent drivers from falling asleep.

[Organization of a medical occupational rehabilitation system for locomotive team workers]. / Organizatsiia sistemy meditsinskoi professional'noi reabilitatsii rabotnikov lokomotivnykh brigad.

The paper deals with the setting up of a system for early diagnosis of premorbidity and for medical professional rehabilitation of locomotive teams. Non-drug preventive measures are shown to have a high rehabilitative effect.

[The characteristics of the electrodermal activity during changes in the level of human wakefulness]. / Osobennosti élektrodermal'noi aktivnosti pri izmeneniiakh urovnia bodrstvovaniia cheloveka.

The wake-drowsiness transition during the performance of a monotonous psychomotor test was studied using polygraphic recording, with particular emphasis on changes in the electrodermal activity (EDA) and occurrence of electrodermal reactions (EDR). It was found that decrease in wakefulness was accompanied by a drop of the EDA. The EDR gradually disappeared for several minutes and did not reappear without activation; their dependence on sex and individual features of a subject significantly increased. It is suggested that discrepancies in the experimental results of psychophysiological studies with EDA may be explained by an insufficient control of the subject's alertness throughout the experiment. Examples of such discrepancies are given: disagreement of sex differences in the EDA, differentiation between EDA-labile and EDA-stable persons, on a possibility of recording the "emotional" EDA from different parts of human body etc. The ways of reproducibility of the results are discussed including the recording of several wake-drowsiness transitions and better recognition of the EDR.

[Medical rehabilitation of locomotive team personnel as a system of measures aimed at disease prevention]. / Meditsinskaia reabilitatsiia personala lokomotivnykh brigad kak sistema meropriiatii po preduprezhdeniiu razvitiia patologicheskikh sostoianii.

Validates the concept and recommendations for the occupational medical rehabilitation of workers of locomotive teams. The scheme of medical rehabilitation includes diagnosis of prenosological states, assessment of the health status, and measures of general health improvement.

[Changes in sleep with different types of reaction to emotional stress]. / Izmeneniia sna pri razlichnykh tipakh reagirovaniia na émotsional'nyi stress.

Polygraphic study of night sleep, carried out on 21 students the night after an examination and one night after vacations, revealed two types of reactions to an emotional stress. It has been shown that in the case of a rapid normalization of vegetative and electromyographic manifestations following the end of an emotional stress impact, the structure of night sleep remains unchanged. When manifestations of the emotional stress persist after the elimination of the stress situation, the amount of the rapid sleep in the following night increases. It is suggested that the differences noted are related to different types of anxiety stress.