NIRS-SPM Analysis of Body Schema Modification and Performance of Body Motion
Takumi Watanabe, Toshiki Fujiwara, Satoshi V. Suzuki · 2018
On manipulation of objects for a person, body schema modification plays an important role to grasp the spatial relation between he/she and the object. In order to investigate the relation between body schema modification and performance of the spatial manipulation in this study, participants performed a task of tracing Japanese characters using sticks having different lengths, and their cerebral blood flow were measured during the task. Since body schema is a higher-order function of the brain, statistical parametric mapping (SPM) was used to elucidate the function. More over an improvement of the task performance by interference to the body schema by applying transcutaneous electrical nerve stimulation (TENS) with different intensities was tried, where the task performance means accuracy of the manipulation of object. Applying SPM analysis, a significant difference at Brodmann area 7 (BA7) and BA40 was confirmed when length of stick was the longest, which induced strongest body schema modification in our experimental condition. There was a significant difference in BA21 and BA39 when accuracy of the manipulation of object was different according to the length of the stick. Applying TENS to enhance the body schema modification, a significant different activation in BA19 and BA37 was confirmed. In conclusion, the brain part which related to accuracy of the hand manipulation were clarified. Moreover, we suggested TENS enable to change accuracy of the hand manipulation.