Schedule of Events | Symposia

Functional connectivity in the neural systems underlying cross-education for tool-use

Poster Session B - Sunday, March 30, 2025, 8:00 – 10:00 am EDT, Back Bay Ballroom/Republic Ballroom

Sayori Takeda¹, Kouji Takano¹, Tomoaki Komatsu¹, Kimihiro Nakamura¹; ¹Research Institute of the National Rehabilitation Center for Persons with Disabilities

Cross-education (CE) is a neurophysiological phenomenon in which motor skills trained in one hand generalize to the contralateral side via plastic changes in shared motor neural systems responsible for both hands (Ossmy, 2016). Motor learning via CE may provide a promising strategy for regaining tool-use ability with a paralyzed hand in neurocognitive rehabilitation. However, the neural basis of tool-use learning through CE remains unclear in humans. Twenty-eight right-handed participants volunteered for the study. During a 16-minute practice, half of them used their left hand to manipulate a special pair of pliers (“training”), whereas the other half only held the pliers with their left hand (“control”). For each hand, tool-use skill was assessed by measuring the time taken to move 20 small balls with the pliers (movement-time). Functional MRI data were acquired to examine practice-related changes in resting-state functional connectivity (RSFC) between the right primary motor cortex (M1) and bilateral supramarginal gyrus (SMG) and supplementary motor area (SMA). The training group performed the behavioral motor task faster than the control group for both hands. The magnitude of this movement-time reduction was correlated between the left and right hands (p < 0.05). Tool-use training increased RSFC between the right M1, right SMG and left SMA (FDR-p < 0.05). This increase in RSFC was correlated with movement-time reduction for both hands (p < 0.05). These results suggest that interhemispheric memory transfer via the left SMA contributes to the rapid behavioral effects of tool-use learning via CE.

Topic Area: LONG-TERM MEMORY: Skill Learning