The variety of visual perceptual impairments in pre-school children with perinatal brain damage

To study the selectivity of visual perceptual impairment in children with e arly brain injury, eight visual perceptual tasks (L94), were administered t o congenitally disabled children both with and without risk for cerebral vi sual impairment (CVI). The battery comprised six object-recognition and two visuoconstructive tasks, Seven tasks were newly designed. For these normat ive data are presented (age 2.75-6.50 years). Because the recognition tasks required object naming, each item included a canonical control drawing and visual perceptual ability was evaluated relative to the non-verbal intelli gence level, instead of chronological age. In 22 multiple disabled children with no indications of CVI, the frequency of impairment did not exceed tha t in the reference sample for any L94 task. In contrast, in 57 5-year-old c hildren who were at risk for CVI due to pre-maturity or birth asphyxia, a s ignificant increase in the frequency of impairment was seen on six L94 task s (range 12-38%). However, only five children had more than two impairments , indicating that the deficits were selective, not pervasive. We conclude t hat early brain lesions interfere with the functioning of particular visual subsystems, yet leave other subsystems intact and functioning within the n ormal range. (C) 2001 Elsevier Science BN. All rights reserved.