The development of symmetrical OKN in infants: quantification based on OKN acuity for nasalward versus temporalward motion.
We quantified OKN asymmetry in 140 normal infants, 3-24 months old, by varying spatial frequency to determine OKN acuity for temporal-to-nasal (T-N) versus nasal-to-temporal (N-T) motion. At all ages, OKN acuity was asymmetrical (better for T-N than for N-T motion) but the size of the asymmetry decreased from 3.2 to 0.7 octaves between 3-24 months, primarily because of improvements in OKN acuity for N-T motion. The results suggest that immaturities in the cortical pathways involved in OKN persist until at least 2 years of age.
Lewis
T L
TL
Department of Psychology, McMaster University, Hamilton, Ont., Canada. lewistl@mcmaster.ca
Maurer
D
D
Chung
J Y
JY
Holmes-Shannon
R
R
Van Schaik
C S
CS
D002657:Child Development / Q000502:physiology*; D002675:Child, Preschool; D006801:Humans; D007223:Infant; D017120:Nystagmus, Optokinetic / Q000502:physiology*; D015349:Vision, Monocular / Q000502:physiology; D014793:Visual Cortex / Q000502:physiology; D014795:Visual Pathways / Q000502:physiology