Exploring the Contribution of the Cerebral Hemispheres to Language Comprehension Deficits in Adults with Developmental Language Disorder

University Of Kansas Center For Research Inc, Lawrence KS

Investigators

Abstract

Deficits in word finding and language comprehension are a significant problem for adult readers with a history of developmental language disorder (DLD; Condus et al, 1986; Felton, 1993; German, 1987, 1989; Hyde Wright et al, 1993; Rudel et al, 1982). Much of the research designed to study these language deficits in children and adults has preferentially looked for functional or anatomical anomalies in the left cerebral hemisphere (LH; Galaburda, Sherman, Rosen, Aboitiz, & Geschwind, 1985; Cohen, Campbell, & Yaghmai, 1989; Galaburda, 1989; Hynd, Semrud-Clikeman, Lorys, Novey, & Eliopulos, 1990). However, in the neuropsychology literature, a growing body of empirical work strongly suggests that the right cerebral hemisphere (RH) also plays an important role in language comprehension (for a review see Beeman & Chiarello, 1998). Furthermore, recent pilot work (Atchley, Story, & Buchanan, in review) suggests that lexical level processing in the RH is impaired in adult readers who have experienced DLD. This research project applies this new understanding of the role of the RH in language comprehension to the study of adult readers with DLD. There are two goals served by these studies. First, to determine the underlying functional neuroanatomy that leads to language comprehension deficits in adults with DLD. Secondly, to better model how these lexical level reading difficulties might contribute to higher order discourse integration and sentence comprehension problems. The research will add to our understanding of both the behavioral and physiological dissimilarities between adults with a history of DLD and adults with normal reading skills.