Noun-verb naming in aphasia: a voxel-based lesion-symptom mapping study

Single case and anatomo-correlative studies of aphasic participants have indicated that lesions in temporal regions cause predominant noun impairment, whereas lesions in frontal areas affect verb processing. These studies, however, relied mostly on arbitrary cut-offs, grouping participants according to whether or not they showed a noun or a verb deficit. Here, instead, we applied a recent anatomo-correlation technique, voxel-based lesion symptom mapping (VLSM) to a group of 16 left-hemisphere stroke participants tested on noun and verb naming tasks. Behavioral and lesion data were collected continuously without establishing a priori two different groups of participants. Noun naming was associated with regions located in the left superior temporal areas, whereas verb naming involved a larger region extending from the left prefrontal to the superior temporal areas. The differences and similarities of the two networks are discussed.