The impact of early unilateral brain injury on perceptual organization and visual memory.

Studies of young children with early unilateral brain injury have suggested that while hemispheric differences in visuospatial processing appear to be present early in development, the young brain is better able to compensate for injury than when the injury occurs later, after networks have been established. The aim of this study was to determine if this pattern continues later in development when these children are given a challenging task: the Rey-Osterrieth Complex Figure. Experiment 1 included longitudinal data from ten children with early left hemisphere (LH) injury and nine children with early right hemisphere (RH) injury. Injury was presumed to be due to a prenatal or perinatal stroke. Compared with typically developing children, both groups were poorer in copying the figure. With development, these children produced reasonably accurate drawings but continued to use the most immature and piecemeal strategy. In Experiment 2, copy and immediate memory drawings from the 19 children with early unilateral brain injury were collected at a single age (11-14 years). Eight of the ten children with LH injury organized their memory reproductions around the core rectangle but included relatively few additional details. In contrast, only two of the nine children with RH injury organized their memory reproductions around the core rectangle and all but one produced the figure in a piecemeal manner. The results from both studies demonstrate the continuation of subtle deficits in visuospatial analysis with development but also the continued capacity for compensation.