Right Hemisphere Contributions to Lexical Semantics

The purpose of this volume is to present the most significant recent work on the role of the right hemisphere in language processing. The focus is on right hemisphere contributions to lexical semantics: the processes by which the meanings of individual words are accessed and used for subsequent linguistic computations. The individual chapters include contributions on language impairments after right hemisphere injury, the role of the right hemisphere in the language of left hemisphere injured patients, and right hemisphere language processing in neurologically normal individuals. A closing chapter critically reviews these findings and outlines the requirements for a theory of right hemisphere lexical semantics. Many new empirical findings are reported. This is the first collection to focus specifically on the language functions of the right hemisphere. The book will interest researchers in neuropsychology and neurolinguistics, as well as clinicians interested in the rehabilitation of aphasic patients.

Language depends on a normally functioning left hemisphere. This central fact of human cerebral dominance was well established by 19th century aphasiologists and has been repeatedly confirmed by subsequent investiga- tions. Predominance, however, does not imply exclusivity. As demonstrated by the commissurotomy patients studied by Eran Zaidel and associates, the right hemisphere is also capable of subserving some linguistic functions. The question, then, is not whether the right hemisphere can process language, but how and when it does so. This volume focuses on the right hemisphere's contribution to one important aspect oflanguage, lexical semantics. Although the right hemisphere may well be involved in other linguistic functions, such as prosody, the greatest evidence for right hemisphere language competence has been obtained for the processing of word meanings. In addition, cognitive psychology and psycho- linguistics have provided us with well-developed models of the lexicon and lexical access to guide our inquiry. Finally, there are techniques available for studying lateralized lexical processing in the normal as well as in the brain- injured hemispheres. For these reasons, a focus on the lexicon is likely to yield the greatest number of insights about right-hemisphere language processing.

Contents: Word-Naming in Right-Brain-Damaged Subjects.- Appreciation of Metaphoric and Connotative Word Meaning by Brain-Damaged Patients.- The Right Hemisphere's Access to Lexical Meaning: A Function of its Release from Left-Hemisphere Control?- The Variability of Right-Hemisphere Reading Capacities in Global Aphasia.- Semantic Priming in the Intact Brain: Separate Roles for the Right and Left Hemispheres?- Hemispheric Locus of Lexical Congruity Effects: Neuropsychological Reinterpretation of Psycholinguistic Results.- Representation, Control and Interaction: What Would a Theory of Right Hemisphere Lexical Semantics Look Like?- Subject Index.