[Problems of hearing loss in aviation engineers (professional and ecological aspects)]. / Problema tugoukhosti u spetsialistov inzhenerno-aviatsionnoi sluzhby (professional'nye i ekologicheskie aspekty).

Health standards for noise were exceeded 3 times when noise characteristics were measured at jobs and in apartments of engineers engaged in maintenance of modern aircraft. These specialists were exposed to noise in working hours and at night. Audiometry registered hearing problems in 69% of the examinees. 20% of them had hearing loss of the second degree. In engineers living closer to airports hearing was damaged more seriously, especially at frequencies 1000-8000 Hz. This fact demonstrates ecological implication of non-occupational acoustic load. Relevant regression levels were derived from correlation of noise doses with tonal hearing. Natural and experimental investigations proved efficacy of impedancemetry in objective assessment of noise-induced affection of the organ of hearing and hearing restoration in subjects occupationally exposed to noise.

[Current aspects of the noise problem in aviation medicine]. / Sovremennye aspekty problemy shuma v aviatsionnoi meditsine.

The authors discuss the problem of improvement the noise factor prevention in aviation medicine. The analysis of the real acoustic load on aviation engineer specialists, performing maintenance of the modern military aircraft have been given. The authors show the importance of the approach to the aviation noise as an ecological significant factor, that means taking into account the acoustic load during work time as well as during rest-sleep periods. The authors suggested the advanced complex of the preventive measures for the purpose of optimization of the noise exposure on the aviation specialists.

[Intersensory interactions as the basis of methods in enhancing resistance to motion sickness]. / Mezhsensornoe vzaimodeistvie kak osnova metodov povysheniia ustoichivosti k ukachivaniiu.

The paper considers how to improve prophylactic measures for air motion sickness. It outlines the results of experimental investigations to substantiate vestibular selection and training methods based on the use of polysensory vestibular and visual stimulations, somatosensory afferent effects and mental activity in the flight personnel during exercise tests. The developed methods are shown to have a high efficiency in providing good tolerance of vestibular stimulations during flight under the conditions of higher flying educational establishments at the stage of primary flying training.

[Aviation noise as an ecological environmental factor]. / Aviatsionnyi shum kak ékologicheskii faktor sredy obitaniia.

Average diurnal doses of noise, received by aviation engineers servicing up-to-date aircrafts and living near air fields, were analyzed. The doses appeared to outnumber the normal values, especially during the work and the sleep. The examinees living in 1-2 km from air fields were proved to have significantly higher auditory thresholds for 1,000-8,000 Hz, in comparison with the examinees residing 5-6 km apart. The excessive noise associated with no occupational matters worsens the hearing restoration after the work, promotes accumulation of the hearing fatigue. Those facts were proved by experiments with audiometry and impedometry. The studies stressed the importance of aviation noise as ecologic factor.

[Changes in specific sensation in pilots exposed to systematic general vibration]. / Izmeneniia spetsificheskoi retseptsii u letnogo sostova pri sistematicheskom vozdeistvii obshchei vibratsii.

Helicopter pilots exposed to excessive general vibration demonstrate changes of specific sensation (vibrotactile, vestibular, auditory), that could be signs of occupational disorder. Those changes are increased thresholds of vibrotactile sensation, lower vestibulovegetative stability, changed vestibulospinal reflexes, more common occurrence of consistent deafness for voice frequencies in comparison with jet aircraft pilots. Experimental vibration (50-1,800 (m/s2) 2 hour) caused no changes of the vibrotactile and auditory sensation, and the modified vestibular function could prove the increased vestibular reactivity.

[Role of optokinetic stimulation in realizing vestibulospinal reflexes]. / O roli optokineticheskoi stimuliatsii v osushchestvlenii vestibulospinal'nykh refleksov.

This paper presents data about the effect of optokinetic stimulation (OKS) on vestibulospinal reflexes and discusses mechanisms of interaction of the vestibular, optic and proprioceptive sensors during their combined stimulation. The vestibulospinal reflexes were investigated using a 2-minute step test and simultaneous OKS that was produced by a portable optokinetic drum mounted on the head of the test subject. During the tests optokinetic nystagmus was recorded and the angle of body rotation relative to the initial position was measured. It was found that during the step test the body turned along the OKS direction, i. e. towards the slow component of optokinetic nystagmus. During leftward OKS the angle of rotation was larger than during rightward OKS: 406.4 +/- 75.9 deg and 207.5 +/- 40.7 deg, respectively. During leftward OKS loss of equilibrium was recorded 4.5 times more often than during rightward OKS. It has been demonstrated that the capacity to track stimuli moving to the left is lower than that to pursue stimuli moving to the right. It has been shown that there is a correlation between the rate of the optokinetic nystagmus slow phase and the angle of body rotation during the step test. It has been concluded that optokinetic nystagmus can be used as an informative parameter when measuring statokinetic stability in response to multisensory stimulation.

[Effect of altered blood circulation on human nystagmic reactions]. / Vliianie izmenennogo krovoobrashcheniia na nistagmennye reaktsii cheloveka.

Optokinetic and vestibulo-optokinetic nystagmus in response to optokinetic and combined vestibulo-optokinetic stimulation applied during head-down tilt was investigated. Tilt-induced circulation changes produced a modifying effect on nystagmic reactions which included a decrease of optokinetic and vestibulo-optokinetic nystagmus and its subsequent recovery after return to the horizontal position. The absolute parameters of vestibulo-optokinetic nystagmus changed depending on the direction of head movements in the sagittal plane relative to the long axis of the body. Some aspects of the relationships between sensory and nystagmic components of vestibular reactions during "conflict" stimulation of the vestibular and visual sensory systems are discussed.

[Dissociation of vestibular autonomic and sensory reactions]. / O dissotsiatsii vestibulovegetativnykh i vestibulosensornykh reaktsii.

The studies of healthy people and test subjects with vestibular reception disorders yielded data about relative independence of the vestibulo-autonomic and vestibulo-sensory reactions during routine vestibulometric and tilt tests. The subjects with a changed labyrinthine function showed a higher vestibulo-autonomic stability as compared to those with normal hearing. In both groups the sensory component of vestibular reactions did not differ significantly. Hemodynamic changes were found to modify some parameters of the nystagmic reactions.