Cerebral laterality for famous proper nouns: visual recognition by normal subjects

Lexical processing has long been associated with left-hemisphere function, especially for infrequently occurring words. Recently, however, persons with severe aphasia, including word-recognition deficits, were observed to recognize familiar proper nouns. Further, some patients suffering right-hemisphere damage were poorer at identifying famous names than left-hemisphere-damaged subjects. These observations point to the possibility that some property of the right hemisphere provides an advantage for the processing of familiar or personally relevant stimuli. To investigate this possibility, we conducted split-visual-field studies in which we manipulated stimulus sets, recognition task, and exposure duration. Greater accuracy in the right visual field was found for common nouns and unknown proper nouns, and famous proper nouns were overall more accurately recognized. Performance for famous nouns in the two visual fields was not significantly different when the task required categorization into famous or nonfamous and when stimuli most highly rated as familiar were used. These findings support our proposals that (1) both hemispheres can process famous proper nouns and (2) the right hemisphere is specialized for personal relevance.