Accession Number : AD0770760

Title :   Dynamic Asymmetry in Neural Components of the Vestibular System.

Corporate Author : MCGILL UNIV MONTREAL (QUEBEC)

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

Report Date : 1969

Pagination or Media Count : 22

Abstract : An asymmetric form of shaping in the neural response to symmetric sinusoidal rotational stimulation of the semicircular canals has been quantitatively examined in 24 decerebrate cats. Averaged unit responses were obtained from extracellular steel microelectrodes sterotaxically located in vestibular nuclei after penetration through the intact cerebellium via a small occipital trephine. The whole preparation was rotated sinusoidally over a frequency range of 2-0.008 Hz and an angular velocity amplitude range 5-180 degrees per second. The results from 141 averaged responses gave an Sk value of 0.84 (S.E. = 0.018,p < 0.001), indicating an overall tendency to development of an asymmetric, or a skewed, response. From these results, it is concluded that the rising phase of action potential frequency was significantly sharper (steeper) than the falling phase in cutoff responses, but that this was not the case of all-round-firing responses.

Descriptors :   *Vestibular apparatus, *Nervous system, *Semicircular canals, Vision, Rotation, Stress(Physiology), Canada

Subject Categories : Stress Physiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE