Language development in a child with left hemispherectomy

A longitudinal study of a left hemispherectomized boy (AB) was conducted to document linguistic evolution and maturation and determine the extent to which right hemisphere processes allow development of language. Resection of the left hemisphere occurred at age 5 years 6 months, following intractable epilepsy. Tests of language comprehension (pointing, understanding of prepositions, understanding of narratives) and production (naming, repetition, lexical diversity, grammatical production) were administered at ages 6:2, 6:4, 6:6, and 6 years 9 months. Observations showed little progress, if any, in most aspects of linguistic performance. In contrast to studies with left-hemispherectomized children, AB showed only a modest expansion of the semantic lexicon and the phonological repertoire more than a year after the surgical intervention. These observations indirectly suggest (1) poor functional involvement of the right hemisphere in the development of adequate linguistic abilities, (2) the necessary integrity of the LH for adequate development of language, or (3) that variations in individual brain maturation rates may account for AB's linguistic progress.