Exploring the Modulatory Effects of Theta Burst Stimulation on Motor Learning and Motor Cortex Excitability

• Main Authors: Tsai-Nung Chang, 張采穠
• Other Authors: Ming-Chang Chiang
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/31396843556699912300

碩士 === 國立陽明大學 === 生物醫學工程學系 === 105 === The current study applied continuous theta burst stimulation (cTBS) to investigate the changes in motor cortex excitability at different phases of motor learning and also whether the inhibitory effects of cTBS on motor cortex excitability was modulated by contextual interference during practice. The participants were recruited for a 5-day serial reaction time task (SRTT). They practiced three sequences over 2 days, followed by a retention test on Day 5 to evaluate learning. On Days 1 and 2, cTBS was given immediately at the end of practice to interfere with the consolidation of the practiced sequences. The participants were divided into 5 groups: In the three sequences, group 1 and 2 practiced sequences arranged in an interleaved order, where the participants in group 1 received real cTBS, and those in group 2 received sham stimulation. Participants in group 3 and 4 practiced sequences arranged in a repetitive order, where cTBS was real in group 3 but was sham-operated in group 4. Participants in group 5 practiced purely random sequences and received real cTBS after practice. We found that cTBS led to greater inhibition in motor cortical excitability after Day1 stimulation for the participants in the interleaved practice group, compared to those who practiced repetitive sequences. This finding also suggests that cTBS resulted in a context-dependent inhibition on motor cortical excitability, perturbing functional motor circuits induced by practice with higher contextual interference.