Single-case study of left cerebral hemispherectomy: development in the first five years of life.

A prospective single-case study of an infant who underwent surgical removal of the entire left cerebral hemisphere at 6 months of age is presented to address, in part, the issue of cerebral hemispheric specialization of function. Serial developmental assessments were made using standardized clinical instruments. A preoperative assessment revealed normal development while postoperative assessments generally revealed delayed development but with a normal rate of maturation. These results are discussed in relation to the issues of early functional specialization of the cerebral cortex and functional plasticity following early brain trauma. In particular, the evidence is interpreted as suggesting that the effect of left hemispherectomy early in life was effectively to delay normal development, and that no specific impairment of either linguistic-communicative or visual-motor/visual-spatial development was apparent.