Hemispheric alpha asymmetries for auditorily presented words of high and low visual imagery during tasks of recognition and recall of aphasic and normal subjects

Abstract

Abstract Hemispheric alpha asymmetries of normal males, normal females, and male aphasics were observed from anterior and posterior placement sites for recall and recognition of high and low imagery words and during resting conditions. Results revealed no hemispheric asymmetries across tasks and electrode placement sites for the two normal groups. Females were found to have consistently higher mean alpha amplitude values than the normal males across conditions and tasks. Aphasic subjects, both fluent and nonfluent, demonstrated greater right hemisphere alpha suppression across tasks and conditions. No significant alpha asymmetries were found between groups during the resting condition. All subjects recognized more words than they recalled. High imagery words were more readily recognized or recalled than low imagery words. Results of the investigation are discussed relative to greater use of right hemisphere processing resources by aphasic subjects for processing linguistic information.