Plasticity and Spontaneous Activity Pulses in Disused Human Brain Circuits

• DOI: 10.1016/j.neuron.2020.05.007
• Publication Date: 2020-06-16T14:33:06Z
• Authors: Dillan J. Newbold; Timothy O. Laumann; Catherine R. Hoyt; Jacqueline M. Ham...; David F. Montez; Ryan V. Raut; Mario Ortega; Anish Mitra; Ashley N. Nielsen; Derek B. Miller; Babatunde Adeyemo; Annie L. Nguyen; Kristen M. Scheidter; Aaron B. Tanenbaum; Andrew N. Van; Scott Marek; Bradley L. Schlaggar; Alexandre R. Carter; Deanna J. Greene; Evan M. Gordon; Marcus E. Raichle; Steven E. Petersen; Abraham Z. Snyder; Nico U.F. Dosenbach
• Keywords: Male; Restraint, Physical; Neuronal Plasticity; Functional Neuroimaging; Motor Cortex; Magnetic Resonance Imaging; Functional Laterality; Upper Extremity; Casts, Surgical; 03 medical and health sciences; 0302 clinical medicine; Motor Skills; Activities of Daily Living; Neural Pathways; Humans; Female; Muscle Strength

To induce brain plasticity in humans, we casted the dominant upper extremity for 2 weeks and tracked changes in functional connectivity using daily 30-min scans of resting-state functional MRI (rs-fMRI). Casting caused cortical and cerebellar regions controlling the disused extremity to functionally disconnect from the rest of the somatomotor system, while internal connectivity within the disused sub-circuit was maintained. Functional disconnection was evident within 48 h, progressed throughout the cast period, and reversed after cast removal. During the cast period, large, spontaneous pulses of activity propagated through the disused somatomotor sub-circuit. The adult brain seems to rely on regular use to maintain its functional architecture. Disuse-driven spontaneous activity pulses may help preserve functionally disconnected sub-circuits.