[Animal motor behavior under increased pressure]

Changing pressure of the helium-oxygen mixture (6, 36, 70 and 100 Ata) induced a sharp increase of the grooming in guinea pigs. The greatest increase (up to 22.5 movements on the average) occurs during first days of the compression. During decompression, some instability of motor activity is revealed but the grooming still exceeds the control level (2.6). The changes of the grooming reflect physiological processes occurring in the CNS stem and spinal structures. The obvious pattern of the changes of grooming suggests some specific mechanisms of the high pressure effect upon the neural functions and reveals early symptoms of the high pressure neural syndrome.