Nonverbal Semantic Decisions in Severe, Global Aphasia: An fMRI Investigation with Test/Re-test Reliability

Cortical reorganization in post-stroke aphasia is not well understood. This study’s goal was to compare regions of activation correlated with semantic decisions both within and between two subjects. BOLD fMRI was utilized to image individuals with chronic, severe nonfluent aphasia during Yes/No semantic judgments of C-ViC icon sentences. There were significant differences in lateralization and localization of activation between participants. Along with high intrasubject reliability, changes were associated with improvement in one participant’s performance across trials. This study provides reliability in fMRI BOLD studies in severe aphasia, and adds to evidence supporting different roles for L/R hemispheres in aphasia recovery.