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The effect of normobaric hypoxic hypoxia (single and interval training) on the characteristics of human hearing was investigated. The hearing thresholds (tonal audiograms), reaction time of subjects in psychophysical experiments (pause detection, perception of rhythm and target words), and short-term auditory memory were measured before and after hypoxia. The obtained data revealed improvement of the auditory sensitivity and characteristics of working memory, and increasing of response speed. It was demonstrated that interval hypoxic training had positive effect on the processes of auditory perception.

The aim of this study was to characterize the pattern of inspiratory muscle fatigue and to assess the resistance to fatigue of the diaphragm (D), parasternal (PS), sternocleidomastoid (SCM), and scalene (SC) muscles. Nine healthy, untrained male subjects participated in this study. Electromyographic activity (EMG) of D, PS, SCM, and SC was recorded during an incremental cycling test to exhaustion (workload of 1.0 W/kg with 0.5 W/kg increments every 5 min). The before-to-after exercise measurements of maximal inspiratory pressure (MIP) and EMG power spectrum changes were performed. The maximal inspiratory pressure declined about 8.1 % after exercise compared with that in the control condition (124.3 ± 8.5 vs. 114.2 ± 8.9 cmH2O) (P0.05), whereas the peak magnitude of integrated electrical activity of D, PS, SCM, and SC during the post-exercise Müller maneuver was significantly greater in all subjects than that pre-exercise. The extent of inspiratory muscles fatigue was evaluated by analysis of a shift in centroid frequency (fc) of EMG power spectrum. Exercise-induced D fatigue was present in three subjects and PS fatigue was another in two; whereas both D and PC fatigue were observed in four subjects. All subjects demonstrated a significant reduction in fc of SCM and SC. Results indicate that early signs of the fatiguing process might be detected in the D, PS, SCM, and SC muscles during exercise to exhaustion. Fatigue of either D or PS muscles develops selectively or together during exhaustive exercise, depending on the recruitment pattern of respiratory muscles. Accessory inspiratory muscles of the neck are less resistant to fatigue compared with the D and PS muscles.

A series of changes in sensory sphere take place in conditions of extremal and unusual influences. These changes are determined directly by processes at the receptor level and indirectly--by the central interaction. In spite of great variety of the influences, there are some general laws in changes of functional state of afferent systems analogous to biophysical and neurophysiological processes. The evaluation of functional state of sensory systems in such conditions can only proceed on ergonomic base taking into consideration the sensory fatigue as well.

Investigations of over 300 oncological patients and 120 healthy individuals have evidenced a considerable increase in the frequency of detecting antibodies to thyreoglobulin (in the titre 1/80 and higher) in patients with cancer of the breast, sigmoid and stomach in females and a tendency to such increase in cancer of the uterine body, and a number of other localizations.