Integrity of the hippocampus and surrounding white matter is correlated with language training success in aphasia

►Branches from the proximal portion of the middle cerebral artery often supply the mesial temporal lobe including parts of the hippocampus, a structure known to be involved in language learning. Therefore, we assessed whether language recovery in aphasia is related to the proximity of the MCA infarct (relative to the internal carotid artery), and correlated with the structural integrity of the hippocampus and its surrounding white matter in the ipsilesional hemisphere. ►We found that proximity of the infarct, structural damage of the hippocampus and impaired integrity of white matter in the lesioned left hemisphere were highly correlated with the patients' language improvements immediately after a 2-week intensive language training interval and with the retention of these gains 8 months after treatment. ►Thus, our results point toward the critical role of brain areas mediating the encoding and retrieval of episodic memory in language recovery after stroke.