Component specificity in albino VEP asymmetry: maturation of the visual pathway anomaly.

The existence of an isolated albino asymmetry component was investigated in the visual evoked potential (pattern appearance/disappearance response) of 96 albinos ranging in age from 3 months to 65 years. Misrouted optic pathway projections in albinism produce VEP asymmetry across the left and right occiput upon monocular whole field stimulation of a checkerboard pattern (element size, 55'). Our results indicate that the asymmetry which reflects the albino feature is contralateral and is restricted to an early period of the appearance response corresponding to the latency of the CI component. Further support for CI component specificity in albino asymmetry is provided by half-field stimulation in non-albino controls and by the results of a component maturation study in children under 6 years of age.