REDUCTION IN BINOCULAR ENHANCEMENT OF THE VISUAL-EVOKED POTENTIAL DURING DEVELOPMENT ACCOMPANIES INCREASING STEREOACUITY

Purpose: To study the maturation of normal binocular vision. Methods: Binocular visual function has been studied and monocular and binocular pattern reversal visual-evoked potentials (VEP) recorded in 20 normal subjects aged 5 to 43 years. Results: Stereoacuity improved significa ntly between the age of 5 and adulthood. Mean stereoacuity for eight c hildren measured by the Titmus test was 61 seconds of are and 56 secon ds of are by the TNO test. For the 12 adults in the study, correspondi ng mean stereoacuities were 45 and 31 seconds of are. Over the same ti mespan, binocular enhancement of the VEP P100 amplitude decreased. For the children aged 5 to 10 years, the mean binocular VEP enhancement t o 20' checks was 1.60, whereas for young adults it was 1.10. There was no comparable change in the binocular enhancement to 40' checks, with mean binocular enhancement of 1.31 in the children and 1.26 in the yo ung adults. Over the same age range, VEP latency also decreased. Concl usion: During visual maturation, improvement in stereoacuity is accomp anied by a fall in binocular enhancement of the P100 amplitude of the VEP to small checks and a reduction in the P100 latency.