The development of symmetrical OKN in infants: quantification based on OKNacuity for nasalward versus temporalward motion

We quantified OKN asymmetry in 140 normal infants, 3-24 months Old, by vary ing spatial frequency to determine OKN acuity for temporal-to-nasal (T-N) v ersus nasal-to-temporal (N-T) motion. At all ages, OKN acuity was asymmetri cal (better for T-N than for N-T motion) but the size of the asymmetry decr eased from 3.2 to 0.7 octaves between 3-24 months, primarily because of imp rovements in OKN acuity for N-T motion. The results suggest that immaturiti es in the cortical pathways involved in OKN persist until at least 2 years of age. (C) 1999 Elsevier Science Ltd. All rights reserved.