Accession Number : AD0467971

Title :   THRESHOLD OF STIMULATION OF THE HORIZONTAL SEMICIRCULAR CANALS IN MAN WITH PARTICULAR REFERENCE TO THE SIGNIFICANCE OF THE FIRST DERIVATIVE OF ANGULAR ACCELERATION AS A STIMULUS.

Descriptive Note : Research rept.,

Corporate Author : NAVAL SCHOOL OF AVIATION MEDICINE PENSACOLA FLA

Personal Author(s) : Graybiel,Ashton ; Kerr,W. A. ; Hupp,D. I. ; Bartley,S. Howard ; Leamer,Bruce V.

Report Date : 12 MAR 1947

Pagination or Media Count : 22

Abstract : By use of the human centrifuge, records of responses both to constant angular acceleration and to changes in angular acceleration were obtained. The indicator was the oculo-gyral illusion, and three types of responses were obtained: left movement, no movement, and right movement. The responses were made at 20-second intervals and were related to the mean angular acceleration calculated for the preceding 20-second period. The mean change between four 20second periods (80-second) were used. Fairly consistent relationships between the direction and amount of change in acceleration, as expressed in each of the three types of response were obtained. A threshold for change (mean change between four 20-second periods) in both positive and negative angular acceleration was determined to be about 0.12 degrees/sec/sec. It was also found that the reliability of response to constant acceleration decreased as the length of the period to which response referred increased beyond 20 seconds at near-threshold rates. It is possible to obtain a threshold for the effectiveness of the fi9st derivative of acceleration, or the change in the rate of change in velocity. (Author)

Descriptors :   (*SEMICIRCULAR CANALS, PERCEPTION), DETECTION, ACCELERATION, ROTATION, STIMULATION(PHYSIOLOGY), REACTION(PSYCHOLOGY), CENTRIFUGES, TEST METHODS, MOTION, TORQUE, STATISTICAL ANALYSIS, PERFORMANCE(HUMAN), AVIATION MEDICINE

Distribution Statement : APPROVED FOR PUBLIC RELEASE