Arousal Effects and Nystagmus During Prolonged Constant Angular Acceleration

Abstract

Six subjects were given a series of 10 rotary trials in which accelerations of 1.0d`/sec<sup>2</sup> and 1.8d`/sec² were employed for durations of 84 and 50 seconds respectively. Subjective states of arousal were manipulated by instructions. Duration and slow-phase velocity of nystagmus were measured. Qualitative as well as quantitative differences were observed as a function of arousal level. Results indicated: (1) during mentally active states, no decline of nystagmus was evident during stimulation nor was there an abrupt cessation of nystagmus accompanying stimulus termination; (2) during states of mental relaxation, the nystagmic response was reduced, declines during stimulation appeared, and the response occasionally ended prior to, or at the moment of, stimulus termination. Theoretical implications of the findings are discussed.