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.

[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).

[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.

Study of nociceptive flexion reflex in healthy subjects and patients with chronic neuropathic pain syndrome.

Nociceptive flexion reflex was measured in healthy subjects and patients with chronic neuropathic pain (diabetic distal symmetric sensorimotor polyneuropathy). The study of nociceptive flexion reflex revealed reduction of subjective pain threshold and reflex threshold in patients compared with healthy persons reflecting deficit of descending antinociceptive influences in the CNS.

[The use of P300 event-related potentials in the evaluation of the effectiveness of therapy of episodic exertional headaches].

Fifteen healthy individuals and 17 patients with episodic exertional headaches were examined before and after treatment with citalopram using P300 event-related potentials. Unlike healthy controls, patients with headaches before treatment displayed an increase in P300 amplitude and the loss of its habituation, which correlated with a decrease in cognitive functions. The treatment lowered the degree of pain and vegetative syndromes, normalized P300 parameters, and improved cognitive functions. The use of P300 method may be an additional criterion of the effectiveness of therapy in patients with exertional headaches.

[A psychoneurophysiological evaluation of non-specific cerebral systems in patients with permanent autonomic disorders of psychogenic etiology during therapy]. / Psikhoneirofiziologicheskaia otsenka sostoianiia nespetsificheskikh sistem mozga u bol'nykh s permanentnymi vegetativnymi rasstroistvami psikhogennogo kharaktera v protsesse lecheniia.

Fifteen patients with permanent vegetative disorders combined with a pronounced anxiety were examined before and after treatment by the Nott drug. The clinical-and-neurological technique, psychometric evaluation of cognitive functions and the neurophysiological method of acoustic cognitive induced potentials P300 were made use of. Before treatment, pronounced vegetative anxiety-related and cognitive disorders were observed in patients. A reliably decreased amplitude of the P300 peak was noted in patients versus healthy subjects while registering the cognitive induced potentials. After treatment, there was a reliably decreased severity of vegetative, anxious and cognitive disorders in patients; the P300 amplitude went up reliably. Supposedly, the changed P300 amplitude, as observed in patients with permanent vegetative disorders; denotes the malfunction in non-specific limbic-reticular brain structures. A growing P300-peak amplitude combined with the arrest of psychovegetative and anxious disorders and with an improvement of cognitive functions in patients due to therapy are indicative of a lower degree of the functional disintegration in the non-specific limbic-reticular brain structures. Finally, the method of endogenous induced P300 potentials can be used as a diagnostic tool in the objective evaluation of a condition of non-specific brain systems in patients with the psychovegetative syndrome; it can also be an objective criterion in the efficiency assessment of a conducted therapy.

[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.

[The psychological analysis of neurotic and psychosomatic disturbances]. / Psikhologicheskii analiz nevroticheskikh i psikhosomaticheskikh rasstroistv.

The present paper demonstrates that up to a definite moment both groups of the patients manifest approximately the same neurotic disorders. However, the differences in the motivation sphere, frustration tolerance, the mechanisms of psychological defence and the clinical characteristics play an important role in the development of neurosis or psychosomatic disease.

[Characteristics of the night sleep of patients with neuroses and a subjectively good and bad sleep]. / Kharakteristiki nochnogo sna u bol'nykh nevrozami s sub''ektivno khoroshim i plokhim snom.

Polysomnographic analysis of the night sleep in neurotic patients with subjectively good (SGS, 12 patients) and bad (SBS, 18 patients) sleep showed that a certain degree of sleep impairment is an obligatory sign of neurosis, though night sleep characteristics changed in SGS to a greater extent than in SBS, irrespective of clinical equivalence and high anxiousness in both groups. Discriminative analysis provided a reliable differentiation between groups of SGS, SBS and normal with SGS occupying an intermediate position in sleep characteristics. The conclusion is that not only anxiousness, but also the brain somnifacient systems' resistance against challenging factors determine the sleep structure. Of no lesser importance are the general peculiarities of night sleep organization. The role of the 2 stages in sleep regulation are discussed.

[Autonomic disorders in Parkinson disease]. / Vegetativnye rasstroistva pri parkinsonizme.

The authors provide the clinical and laboratory findings regarding the vegetative nervous system in 60 patients with parkinsonism and in 11 healthy volunteers. It has been found that parkinsonism is necessarily associated with vegetative disorders which are pronounced to a greater degree in right-handed patients and bilateral clinical manifestations of the syndrome.

[Topographic selective mapping in patients with disorders of thermoregulation of cerebral origin]. / Toposelektivnoe kartirovanie u bol'nykh s narusheniem termo- reguliatsii tsentral'nogo geneza.

The paper privides the data on topographic selective mapping of electric activity in a state of relaxed consciousness in 11 patients with derangement of thermoregulation of the central genesis compared to a group of patients with vegetative crises. 10 healthy volunteers served as control. On the whole the patients' group was characterized by diffuse augmentation of percentile presentation of the power of slow and regress of rapid ranges. The statistical analysis revealed varying electrophysiological organization in patients with paroxysmal and permanent character of hyperthermia. In the group of patients with paroxysmal temperature rises and vegetative crises, the electrophysiological parameters were identical. In patients with permanent ++sub-febrility, the pattern of spatial electric activity was characterized by qualitative and quantitative differences from the control group.

[Electrophysiological analysis of the functions of the sweat gland fibers in various diseases]. / Elektrofiziologicheskii analiz funktsii potootdelitel'nykh volokon pri razlichnykh zabolevaniiakh.

The authors relate the data on vegetative sweating fibers studied by the method of evoked skin sympathetic potentials in patients with diabetes mellitus, Charcot-Marie atrophy, spinal amyotrophy, Guillain-Barre syndrome, essential hyperhidrosis, and in those with Raynaud's phenomenon and thyrotoxicosis. A remarkable decrease of conduction by sweating fibers was revealed in patients with diabetes mellitus, Charcot-Marie atrophy and Raynaud's phenomenon; a moderate decrease was shown by the patients with Guillain-Barre syndrome and by those with spinal amyotrophy. The conclusion is made about the high information content of the method.

[Cardiovascular tests in various forms of pathology]. / Kardiovaskuliarnye proby pri nekotorykh formakh patologii.

Quantitative estimation of the status of the autonomic nervous system is a research priority in neurology. One of the approaches to its solving lies in the use of cardiovascular tests. The authors brief the mechanisms of the tests, provide their standards. Show the characteristic patterns of the cardiovascular tests in different diseases of both organic and psychogenic nature. Taking into consideration the simplicity, accessibility, and noninvasive nature of the tests, it is recommended that the cardiovascular tests may be employed for estimating the status of the autonomic nervous system in a wide range of diseases of both neurological and somatic origin.

[Evaluation of the autonomic innervation of the pupil]. / Otsenka vegetativnoi innervatsii zrachka.

The purpose of the study was to examine vegetative innervation of the pupil in different diseases associated and not associated with vegetative disorders. In addition to the ++clinico-neurological method, the main method of examination was to study the pupillary cycle (determination of the time of the pupillary cycle (TPC) with the aid of a slit lamp). Fifty healthy test subjects and 262 patients suffering from different somatic and neurologic diseases were examined. The patients were divided in 9 clinical groups: spinal amyotrophy, neural Charcot-Marie amyotrophy, Guillain-Barre syndrome, diabetes mellitus, thyrotoxicosis, hemicrania, Raynaud's disease, idiopathic hyperhidrosis, vegetative crises. The data obtained demonstrate varying grades of the rise of the TPC in the indicated diseases, which reflects varying degrees of vegetative innervation of the pupil insufficiency. However, no well-defined correlation was obtained between the intensity of the psychovegetative syndrome and the TPC. Therefore, it has been shown that the method of determining the TPC is unsophisticated and noninvasive and can be successfully used in different forms of pathology to identify vegetative insufficiency at different stages of the disease.

[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.

[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.

[The state of nociceptive and antinociceptive brain systems in patients with the pain form of diabetic polyneuropathy].

We studied 48 patients with the pain form of distal symmetric sensorimotor diabetic polyneuropathy (DPN) before and after polytherapy and 17 sex- and age-matched healthy people. Clinical/neurological, psychometric and neurophysiologic (recording of nociceptive flexor reflex (NFR) and exteroceptive suppression of involuntary muscle activity) methods were used. Lower NFR thresholds and coefficients pain threshold/reflex threshold (Pt/Rt) as well as the presence of moderately-severe depression and high anxiety level were found in patients with DPN. This reflects a lack of supraspinal and antinociceptive effects and a significant role of psychological factors in the formation of chronic neuropathic pain. The significant reduction of pain, increase of NFR thresholds and Pt/Rt coefficients were seen after the treatment with antidepressants (venlafaxine or pipofezine) in the combination with carbamazepine that suggests the strengthening of supraspinal and antinociceptive systems activity. Measuring of NFR parameters has a practical value for the assessment of the state of antinociceptive brain systems, intensity of pain syndrome, severity of comorbid anxiety-depression disorders and for the objectification of treatment efficacy in patients with DPN.

[Hand motor dysfunctions in computer users].

It were studied 239 female typists aged from 16 to 62 years (mean age 20,1±7,8 years) using author's questionnaire for computer typists to assess hand function and develop preventive measures of disturbances revealed. Indirect signs of tunnel hand neuropathy (27,2%), focal hand dystonia (21,4%) and muscular-tonic syndromes of different localization (18%) have been found. Typists are a risk group of fine hand motor dysfunctions. As preventive measures, authors recommend to use computer auxiliary devices, to change a motor stereotype during the day, to make hand "motor holidays", to organize working place.

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.