P.054 Effects of cerebellar Theta Burst Stimulation (TBS) on working memory

Abstract

Background: Recent evidence suggests that the cerebellum is involved in cognitive functions. Theta burst stimulation (TBS), a modality of transcranial magnetic stimulation (TMS), on the cerebellum can change its contribution to working memory. Therefore, we hypothesize that excitatory intermittent TBS (iTBS) on the cerebellum would improve performance on working memory tasks, whereas inhibitory continuous TBS (cTBS) would disrupt it. Methods: As this is an ongoing study, nine participants (6 women) took part in this study so far. TBS was applied on the cerebellum bilaterally. All subjects received iTBS, cTBS, and sham iTBS in three sessions in random order. After TBS in each session, participants performed three types of working memory tasks: letter 2-back, digit span forward (DSF), and digit span backward (DSB). Results: The preliminary results suggest that participants performed better in the sham condition in the letter 2-back and the DSB tasks compared to the iTBS and cTBS conditions, but the results did not reach statistical significance due to the small sample size. Conclusions: The preliminary results show that the cerebellar contribution to working memory may be disrupted by TBS. As we gain more statistical power by recruiting more participants, we hope to further demonstrate the effects of cerebellar TBS on working memory.