In a new research study, it is demonstrated that the primary brain area involved in hand movement (M1_hand) decreases in size after a 4-weak period of hand immobilization, and that the size recovers after subsequent traning. Thus, even short periods of changed muscle and brain activity can cause brain shape changes in either direction. The findings suggest, for example, that if writing is stopped during school holidays, it may lead to temporary changes in brain structure.

The group behind the study includes Hartwig R. Siebner from the DRCMR as last author. The research was conducted in connection with a treatment study for writer's cramp, which is a medical condition affecting the ability to control the finger muscles during writing. As part of the treatment, the affected hand was immobilized for 4 weeks and subsequently trained for an 8 week period. MRI scanning before the study and at week 4 and 8 showed how the size of M1_hand decreased and recovered. Additionally, transcranial magnetic stimulation (TMS) was used to demonstrate a corresponding temporary decrease in excitability of that brain area.

 Rererences:

Title: Manual activity shapes structure and function in contralateral human motor hand area.

Published in: NeuroImage 2011 Jan 1;54(1):32-41

Authors: Granert O, Peller M, Gaser C, Groppa S, Hallett M, Knutzen A, Deuschl G, Zeuner KE, Siebner HR.

A commentary  on the article was published on the NeuroKüz blog