Maturation of the fast component of vestibular nystagmus during childhood and young adulthood.
Primary nystagmus was evoked by constant angular acceleration at near-threshold levels (0.2, 0.4, and 0.6 degree/s2) in 34 normal human subjects (25 children aged 2-11 years and 9 young adults aged 17-21 years). Acceleration was carried out in complete darkness, and with subjects' eyes open. Analysis of response latencies showed that all subjects responded to acceleration magnitude as low as 0.2 degrees/s2. A decrease in response latency was associated with an increase in acceleration magnitude, and there was no significant effect of age on response latency or its relationship to acceleration. However, a relationship was found between age and the percentage of trials showing the presence of a set of three successive beats during acceleration: a significant increase in the frequency of such trials occurred with increasing age. The relationship of these findings to brainstem vestibular modulatory mechanisms is discussed.
Fuster
M M
MM
School of Medicine, UCLA.
De Traversay
J
J
Ornitz
E M
EM
D000054:Acceleration; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009760:Nystagmus, Physiologic / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D014722:Vestibule, Labyrinth / Q000502:physiology*