Elucidating the neural mechanism to drive the functional recovery of dexterous hand movements after spinal cord injury by prediction error

2021 Fiscal Year Final Research Report

• Project/Area Number: 19H01011
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Medium-sized Section 46:Neuroscience and related fields
• Research Institution: Kyoto University
• Principal Investigator: Isa Tadashi 京都大学, 医学研究科, 教授 (20212805)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 機能回復 / 運動制御 / 脊髄損傷 / 霊長類 / 半球間抑制 / 巧緻運動 / 回路操作 / ウイルスベクター

Outline of Final Research Achievements

Our previous studies showed that after the partial injury of the spinal cord in monkeys, the dexterous hand movements well recovered through rehabilitative trainings. In the present study, we made extensive electrocorticography recordings from bilateral motor-related cortical areas during reach and grasp task, and found that the activity of ipsilesional premotor cortex preceding the movement onset increased during the early recovery period. To study the contribution of the interhemispheric effects from the contralesional side, we selectively blocked the callosal fibers using the double viral vector technique with DREADD, and found that the interhemisoheric inhibition before the injury turned to interhemispheric facilitation during recovery and promoted contribution of the ipsilesional premotor cortex to recovery of hand functions.

Free Research Field

神経生理学

Academic Significance and Societal Importance of the Research Achievements

従来より脳卒中や脊髄損傷の患者において、障害された手と同側の皮質運動関連領野の活動が増加することが知られていたが、その意義は明らかでなかった。今回の一連の研究により、少なくとも回復初期において、障害同側運動前野の活動が、脱抑制によって、反対側皮質によってもたらされ、かつ機能回復に貢献していることが明らかになったことは、運動障害のリハビリテーション治療を体系づける上での意義は大きいと考える。