The alteration of hearing process in antiorthostatic position modelling microgravitation
Abstract
The cranial shifting of body fluids developing in microgravity can be modelled by –300 head-down tilt body position (antiorthostatic posture) on Earth. Authors examined a group of 13 healthy voluntary young men in antiorthostatic posture and recorded the alteration of parameters in complex examinations. Among them pure tone threshold and speech threshold examinations were carried out. Pure tone audiometry and speech audiometry examinations were made separately in both ears in camera silenta on the first day. On the second day the pure tone threshold and speech threshold levels were determined by binaural examination in sitting position in that room, where the antiorthostatic posture was performed, and the background noise of the room was also simultaneously measured. The examinations were repeated in the 171st minute of antiorthostatic posture. In the 181st minute the examined volunteers were put into +700 orthostatic position and the audiological tests were also repeated. Authors found the elevation of both the pure tone threshold and the speech threshold levels in the course of loading.
