Improving Lexicosemantic Impairments in Post-Stroke Aphasia Using rTMS Targeting the Right Anterior Temporal Lobe

Background/Objectives: Repetitive Transcranial Magnetic Stimulation (rTMS) can enhance post-stroke aphasia recovery. The right Inferior Frontal Gyrus is the most common target in rTMS studies for inhibitory stimulation. However, lexicosemantic processes involve a large brain network including the Anterior Temporal Lobe (ATL). We hypothesize that rTMS targeting the ATL will improve lexicosemantic impairments in PWA. Methods: In a Single-Case Experimental Design, three PWA with lexicosemantic impairments performed a Picture and Auditory Naming, and a Semantic Decision tasks, five times a week for one or two weeks, to establish baseline scores. Then, each participant received continuous inhibitory Theta Burst Stimulation targeting the right ATL, five times a week for two weeks. After each rTMS session, participants performed all linguistic tasks. A follow-up measurement was performed one month after the end of the study. Results: All participants showed significant improvement in the Picture Naming task, while only P1 improved in Auditory Naming accuracy. In the Semantic Decision task, only P2 showed improvement in both accuracy and RT, while P1 showed improvement in RT alone and P3 showed no improvement. Conclusions: The results suggest that ATL is a promising target for brain stimulation therapy in aphasia for participants with lexicosemantic impairments. RTMS to ATL may modulate the connected ventral semantic stream, leading to imporvements in lexical access. This study highlights the possibility of choosing the cortical target for rTMS based on the clinical profile of the participant, making it potentially more accessible to clinicians.