Lesion locations associated with speech perception deficits following penetrating head injury

Speech discrimination and identification tasks assessing voicing and place distinctions were given to 16 unilaterally brain injured subjects free of aphasic or dysarthric symptoms 12-15 yr post head injury. Seven subjects did not demonstrate any difficulty with these speech tasks, while five left- and four right-brain-injured subjects showed moderate difficulties. These difficulties were more pronounced on the discrimination than on the identification tasks. Analysis of CT scans demonstrated that the lesion locations most clearly associated with the speech discrimination deficits were upper levels of the white matter subjacent to cortical regions in either hemisphere.