Accession Number : AD0762098

Title :   Frequency Response Analysis of Central Vestibular Unit Activity Resulting from Rotational Stimulation of the Semicircular Canals,

Corporate Author : MCGILL UNIV MONTREAL (QUEBEC) DRB AVIATION MEDICAL RESEARCH UNIT

Personal Author(s) : Jones,G. Melvill ; Milsum,J. H.

Report Date : 16 JUN 1971

Pagination or Media Count : 26

Abstract : The neural response of semicircular canal-dependent units in the vestibular nuclei of cats was examined over a frequency range of sinusoidal rotation extending from 0.004 to 0.9 Hz. Frequency-response analysis indicates that, over the range examined the information contained in the neural signal received by the brain stem was similar to that expected from the mechanical end-organ. Over the experimental frequency range, the relation between neural response and mechanical stimulus was found to be dominated by a single time constant of about 4 sec. Above this frequency the information content of the neural signal tends towards that of angular velocity and below that frequency it tends towards that of angular acceleration. It is inferred that the so-called 'long' time constant of the cat's horizontal canal is about 4 sec and that during most normal head movements containing frequencies below about 1 Hz the informational mode of neural signals generated in the canal and receive in the brain stem probably tends towards that of head angular velocity. This seems appropriate for the generation of vestibulo-ocular reflex compensation for head movement and for reflex damping (negative velocity feed-back) of unintended head and body movements.

Descriptors :   (*SEMICIRCULAR CANALS, *ROTATION), VELOCITY, VESTIBULAR APPARATUS, STRESS(PHYSIOLOGY), STIMULATION(PHYSIOLOGY), END ORGANS, NERVOUS SYSTEM, PHYSIOLOGY, CANADA

Subject Categories : Stress Physiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE