Poster Session E, Monday, March 25, 2:30 – 4:30 pm, Pacific Concourse
Learning-induced transition of mapping high-dimensional motor space in a complicated reward-based motor skill learning
Sungshin Kim1,2, Yera Choi1, Emily Yunha Shin1; 1Center for Neuroscience Imaging Research, Institute of Basic Sciences, 2Sungkyunkwan University
Human motor skill learning is a complicated process of generating a novel movement pattern to achieve a task goal. To date, most neuroimaging studies investigating neural mechanism of motor skill learning have employed target-reaching, sequential force control, or sequence learning tasks and little research has involved a more complicated motor skill learning task. Here, we designed a novel fMRI experiment in which subjects wear a MR-compatible data-glove and learn to control a computer cursor over a 5-by-5 grid by manipulating fingers. To investigate how extensive training changes neural representation of mapping between high-dimensional motor space and low-dimensional task space, subjects participated in two fMRI sessions separated by five training sessions. The extensive training decreased interaction between the motor and visual modules but increased interaction between the motor and reward modules. We also found the central executive, salience, and dorsal/ventral attention networks were strongly modulated by trial-by-trial reward in the early learning phase, but the extensive training reduced the sensitivity of these networks to the rewards. Interestingly, the rewards also modulated activities in the hippocampal-cortical declarative memory network. As a result of the extensive training, the modulated region shifted from anterior and mid portion to posterior portion of hippocampus and posterior cingulate regions, substantiating their respective roles of encoding and retrieval of spatial mapping.
Topic Area: LONG-TERM MEMORY: Skill learning