Preliminary Study of Topographic Visual Evoked Potential Mapping in Children with Permanent Cortical Visual Impairment

Abstract

The assessment of cortical visual impairment in handicapped children is often difficult and the diagnosis may be delayed for several years, particularly when the child is difficult to examine [1]. The striate cortex receives and transmits visual information to the association areas. Thus it governs the ability to resolve fine detail (visual acuity) and acts as a gateway to conscious visual analysis. More complex visual interpretation occurs in the association areas. Total destruction of the striate cortex results in loss of vision for conscious visual analysis. Destruction of the association areas results in visual agnosia and such individuals see without being able to recognise. Because of the similarities in their visual behaviour, it is difficult clinically to distinguish between profound visual agnosia and severe loss of visual acuity in multihandicapped children.