[The factors impact on the urgent daytime sleepiness degree in the Parkinson's disease]. / Faktory, vliyayushchie na stepen' imperativnosti dnevnykh zasypanii pri bolezni Parkinsona.

One of the main manifestations of excessive daytime sleepiness (EDS) among patients with Parkinson's disease is sudden-onset sleep (SOS). The SOS episodes could dramatically increase the traumatic ratio among those patients. The factors of SOS among PD patients are not well understood. OBJECTIVE: Describe the clinical and physiological features of patients with different types of SOS for detection of influencing factors of urgent EDS. MATERIAL AND METHODS: 32 patients SOS positive (17 female) were included. The median age was 66.5±7.8; the median PD duration was 9.2±4.3 years (2.66±0.5 Hoehn-Yahr). The patients received the levodopa - dopamine receptors agonist combined medications. Moreover, the Unified Parkinson's disease rating scale (UPDRS parts II, III in an «on¼ state of dopaminergic medication), the diary of the assessment of the waking period, the Epworth Sleepiness Scale, the Parkinson Disease Sleep Scale I (PDSS I), the Scales for Outcomes of Parkinson's disease-Cognition (SCOPA-Cog), the Beck Depression Inventory, the State-Trait Anxiety Inventory, the Apathy Scale, the Stroop test, objective sleep-wake assessment: standard nocturnal video-polysomnography (PSG), multiple sleep latency tests (MSLT) were used. Besides, we compare patients' clinical and neuropsychological characteristics (especially EDS sense) before the SOS. RESULTS: 36% of patients describe the SOS without preexisting sleepiness (group 1). The short-time period of sleepiness notes approximately 64% SOS patients before the sleeping period (group 2). Group 1 has the less prominent activity of daily living compared to group 2. Moreover, group 1 patients have significantly lower subjective and objective severity of night sleep disorders (higher total score value of SOS BP, longer 3rd stage of sleep duration), lesser severity of the Epworth and apathy scale (p<0.05). The group 2 patients with a low ability to resist the onset of SOS (less than 5 minutes) differed from patients with greater resistance. Firstly, by a greater degree of disturbances in daily activities (ASOBP, section 2), shorter latent periods 1, 3 stages, shorter duration of 1 stage of night sleep; more prominent anxiety, depression and impaired attention (p<0.05). The narcoleptic-like falling asleep syndrome was diagnosed in 9 (28%) cases with SOS, without significant difference between the groups. CONCLUSION: SOS among patients without EDS are an independent manifestation of PD. The degree of SOS urgency is affected by the severity of the activity of daily living, anxiety, depression, and attention disorders.

[Daytime sleepiness and cognitive disorders in elderly patients]. / Dnevnaia sonlivost' i kognitivnye rasstroistva v pozhilom vozraste.

Data on the contribution of daytime sleepiness to cognitive impairment in elderly patients are presented. Currently, diagnostic methods of daytime sleepiness, which include diaries, neurological, clinical and instrumental tools, are used. It has been shown that daytime sleepiness correlates with different types of dementia that suggests the involvement of common neurochemical mechanisms. Multiple studies report that daytime sleepiness increases the risk of dementia in elderly people. Future research of daytime sleepiness could be focused on its clinical and paraclinical presentations to facilitate the prognosis of dementia.

Dynamics of Alpha Rhythm Peak Frequency during Falling Asleep.

Changes in the frequency characteristics of EEG alpha rhythm in during falling asleep were studied in three healthy individuals under conditions of long-term isolation (MARS-500 project). Falling asleep was preceded by enhanced alpha rhythm frequency. An inverse correlation between the duration of falling asleep and prevailing alpha rhythm frequency during active and relaxed wakefulness was revealed in the left hemisphere. These results demonstrate the principal possibility of predicting the duration of falling asleep by using alpha rhythm spectral analysis. It is assumed that the frequency of the alpha range spectral peak can be a marker of drowsiness and reflect the current need for sleep.

[Night sleep structural alteration as a function of individual strategy of adapting to 520-isolation].

Purpose of the work was to establish a relationship between trends in sleep alteration and individual adaptation to the stress-factors in the 520-day isolation study. Psychological evaluations using a battery of motivation tests and L. Sobchik's modification of the Luscher personality test, and Mirror coordinograph enabled to differentiate groups reacting to the stress on the pattern of "control" (G-1) or "search" (G-2) manifested in individual styles of behavior and operator's activity. The 2 groups showed different dynamics of the night sleep structure. Difficulties with falling asleep in G-1 arose on the eve of "landing onto Mars" and end of the experiment, whereas in G-2 they were evident prior to the end only. Besides, the micro- and segmental sleep structures were more stable in G-1 suggesting the integrity of somnogenic mechanisms despite difficult sleep initiation.

[The psychophysiological features of nonepileptic paroxysmal disorders].

22 patients with panic disorder without agoraphobia, 19 patients with paroxysmal atrial fibrillation and 43 healthy control subjects with use clinic technique, psychometric, neuropsychological, neurophysiological methods (quantitative EEG and auditory event-related potentials P300) were examined. Patients with panic disorder was differed from patients with paroxysmal atrial fibrillation by higher level of anxiety and greater degree cognitive functions disturbances. In comparison with healthy control subjects at panic disorders increased of P300 peak amplitude and the spectral power of EEG beta and theta bands in the right hemisphere was observed, at paroxysmal atrial fibrillation--decreased of P300 peak amplitude and the spectral power of EEG beta band in the both hemispheres. Obtained data may indicate various origin mechanisms of paroxysmal states or neurotic condition (panic disorder) and psychosomatic (paroxysmal atrial fibrillation).

[Psychophysiological characteristics of panic disorder and generalized anxiety disorder].

We studied 34 patients with panic disorder, 32 patients with generalized anxiety disorder and 29 healthy controls using clinical-neurological, psychometric, neuropsychological and neurophysiological (auditory event-related potentials) methods. Patients were characterized by pronounced autonomic dysfunctions, a higher level of anxiety and depression as well as cognitive function disturbances in the form of impairment of short-term memory and directed attention in comparison with healthy controls. Patients with generalized anxiety disorder differed from patients with panic disorder by the higher level of anxiety, greater degree of depression and more expressed disturbances of short-term memory and directed attention. Compared to controls, patients with generalized anxiety disorder had lower P300 amplitudes while the latter was higher in patients with panic disorders. It is concluded that recording of event-related potentials may be used as an additional method of differential diagnosis of these types of anxiety disorders.

[Sleep structure instability in healthy men under conditions of 105-day isolation experiment "Mars-105"].

Night-to-night stability of falling asleep and duration of wakefulness in the sleep was studied in six healthy male subjects under conditions of 105-day isolation experiment "Mars-105". Polysomnography records were carried out in each subject during five nights taken in regular intervals within the experiment. Three subjects demonstrated high stability of falling asleep and wakefulness in sleep (group I), whereas in the remaining three subjects stability of these characteristics was low (group [I). Delta-sleep was shown to be deepened in subjects of group II (significant prevalence of stage 4 (47.3 min) over stage 3 (32.9 min)). In subjects of group I, the duration of stage 3 was 44.9 min and that of stage 4 was 26.6 min. We suggest that night-to-night instability of falling asleep and duration of wakefulness in sleep in combination with delta sleep is the special individual form of sleep adaptation to conditions of chronic isolation stress.

[Effects of long-term isolation and anticipation of significant event on sleep: results of the project "Mars-520"].

The purpose of the research was to study effect of long-term isolation on night sleep. The data were collected during international ground simulation of an interplanetary manned flight--"Mars-500". The polysomnographic recordings of six healthy men were performed before, four times during and after 520-days confinement. During the isolation sleep efficiency and delta-latency decreased, while sleep latency increased. Post-hoc analysis demonstrate significant differences between background and the last (1.5 months before the end of the experiment) measure during isolation. Frequency of nights with low sleep efficiency rose on the eve of the important for the crew events (simulation of Mars landing and the end of the confinement). Two weeks after the landing simulation, amount of the nights with a low sleep efficiency significantly decreased. Therefore, anticipation of significant event under condition of long-term isolation might result in sleep worsening in previously healthy men, predominantly difficulties getting to sleep.

Interhemispheric EEG asymmetry in patients with insomnia during nocturnal sleep.

Sleep EEG was recorded and analyzed in patients with neurotic insomnia. It was found that interhemispheric asymmetry in the same individual can vary during sleep from right-hemispheric to left-hemispheric. Interhemispheric EEG asymmetry is closely related to the stage of sleep. The development of left-hemisphere or right-hemisphere asymmetry is mainly determined by activity of the right hemisphere. The development of interhemispheric asymmetry during wakefulness, stages 1 and 2 sleep, and delta sleep is mediated by common mechanisms.

[Specific features of the structure of sleep and personality under the conditions of chronic emotional stress and methods of improving the adaptive abilities of man]. / Osobennosti struktury sna i lichnosti v usloviiakh khronicheskogo émotsional'nogo stressa i metody povysheniia adaptivnykh vozmozhnostei cheloveka.

The results of a complex psychophysiological study of human sleep in the chronic stress condition are described. 20 patients with complaints of night sleep disturbances in the chronic stress condition and 10 healthy controls were examined by polysomnography. Profound changes of the quantitative and qualitative sleep parameters, mainly, related with the slow sleep phase, sleep delta characteristics and adaptive wakefulness mechanisms. The study demonstrated the effectiveness of improving the human adaptive parameters in the chronic stress conditions by using the drug and drugless therapy methods.

[Segmental organization of sleep]. / Segmentarnaia organizatsiia sna.

Segmental organization of sleep was studied in healthy subjects and insomniac patients. Theoretical and practical aspects of sleep organization are discussed. The disintegration syndrome (decreased stability of development of sleep stage segments and change in sleep stage sequence characteristic of normal sleep) is an inherent feature of sleep disorders and a fine index of adaptive possibilities of sleep systems. It is suggested that each segment of any sleep stage has its specific functional role different from the functional significance of the stage as a whole. Depending on the time of appearance of any specific segment, it can be an important preliminary of transition to another functional state and be involved in preparation for triggering corresponding sleep-organizing systems. At the same time, it can be a reflection of the process of estimation of the achieved result. The dynamic change in sleep stages is determined by subsequent activation of different brain structures and also suggests a possibility of a change in the functional role of a certain stage depending on the initial functional state of sleep systems.

Stages of sleep after psychoemotional tension: the individual character of changes.

This report describes complex psychophysiological studies of nocturnal sleep in healthy humans in normal concentrations and after emotional tension. A series of contemporary methods was used: questionnaires, psychological tests, motor tests, and polysomnography with heart rate recording. These experiments showed that psychoemotional tension induced changes mainly in the structure of the first sleep cycle, decreasing the proportion of the second stage of slow sleep in total nocturnal sleep, led to a redistribution of delta sleep, increasing delta sleep in the second half of nocturnal sleep, and suppressed the mechanisms underlying the organization of the phases of rapid sleep. Psychoemotional tension affected human cerebrovisceral functions, for example inducing increases in the frequency and variability of the heart rhythm during nocturnal sleep. The nature of these changes in sleep structure and autonomic responses depended on the personality characteristics of the individual person. Thus, the individual approach to the question of psychoemotional stress in sleep disturbances is, we believe, the most appropriate.

[Sleep stages after psychoemotional exposure: individuality-dependent changes]. / Stadii sna posle psikhoémotsional'nykh vozdeistvii: individual'nost' izmenenii.

Sleep stages were studied in healthy subjects with the aid of a battery of tests involving questionnaires, psycho-tests, motor tests, polysomnography, and cardiomonitoring. An induced psychoemotional tension was shown to change the 1st sleep stage, to decrease percentage of the 2nd stage of the slow-wave sleep, to redistribute the delta-sleep, and to suppress the REM sleep mechanism. The cerebro-visceral function of increasing the heart rate and its variability in night sleep was also affected. Patterns of the sleep structure changes depended on personality characteristics of the subjects. Thereupon, individual programs should be used in studies of psychoemotional stress effects upon the sleep pattern.

[The effect of Imovane on sleep structure and respiratory indices during sleep in insomnia patients]. / Vliianie imovana na strukturu sna i nekotorye pokateli dykhaniia vo sne u bol'nykh insomniei.

Night sleep was examined in 120 patients with different forms of insomnia. The positive effect of Imovane was shown both on presomnic and intrasomnic disorders. Transitory side effects (dryness, bitter taste in the mouth) were in some cases that didn't need cessation of therapy. Polysomnographic studies confirmed effectivity of Imovane: there were observed either lengthening of the duration of sleep, its 2 stage, delta-sleep, or decrease of the duration of falling asleep. There were no respiratory changes after course of Imovane, meanwhile some indices positive dynamics was revealed in this case.

[The typology of the objective disorders of night sleep in insomnia]. / Tipologiia ob''ektivnykh narushenii nochnogo sna pri insomnii.

The most frequent polygraphic manifestations of insomnia were analysed in 39 neurotic patients with disorders of night sleep (NS). The frequency of pathological alterations of the objective characteristics of NS was determined after examination of the data obtained. Four types of sleep alterations were recognized. There was not always clear correlation between the subjective estimation of sleep and its objective characteristics. For choice of optimal therapeutic policy it was proposed to evaluate leading complaints of the patients for more accurate definition of the degree of expression of objective manifestations of insomnia without usage of NS polygraphy. Possible mechanisms of NS disorders were determined. Classification of different types of objective disorders of sleep in insomnia was elaborated.

[The wakefulness-sleep cycle during antiorthostatic hypokinesia]. / Tsikl "son-bodrstvovanie" v usloviiakh antiortostaticheskoi gipokinesii.

Studies on the wake-sleep cycle with participation of eight female volunteers were performed before, during, and after a 120-day bed rest with the head-end of bed tilted down at 6 degrees (HDT). Methods of polysomnography and actography were applied. The test-subjects were assigned into 2 groups. Group A was prescribed to use countermeasures throughout the experiment; no countermeasures was administered by group B. Evidence of significant alteration in sleep structure at different time points in HDT is given in comparison with data about females of the control group under the conditions of everyday activity. Sleep deviations in the subjects were reordered at each of the three points of investigation and differed from those in control. HDT was shown to modify the sleep structure in experimental groups A and B. A supposition is made that under these conditions the dynamics of physical activity during night sleep had an adaptive character.

[Features of the sleep/wakefulness cycle in long-term isolation]. / Osobennosti tsikla "Son-bodrstvovanie" v usloviiakh dlitel'noi izoliatsii.

The sleep/wakefulness cycle was the subject of polysomonographic and actographic studies in two experiments with isolation and confinement of six volunteer operators for 135 and 90 days. The dynamics of sleep structure was the target parameter before, during, and after the experiments. The sleep structure dynamics and changes in the motor activity differed in their directionality. At all the stages of experiments the operators' sleep structure had some unique peculiarities. Discussion is centered around the cases of shortened duration of delta-sleep and altered latent periods of specific stages. During the off-nominal situation (ONS) with 45 hour sleep deprivation polysomnographs recorded episodes of latent sleep which became more multiple during the second ONS and were combined with signs of "slow" sleep, and increases in the index of motor activity during night sleep post ONS. Hence, adaptation to changed physical and social environments is manifested by a specific functional restructurization of the sleep/wakefulness cycle.