Neural network remodeling underlying motor map reorganization induced by rehabilitative training after ischemic stroke

Publication date: 17 December 2016 Source:Neuroscience, Volume 339 Author(s): Naohiko Okabe, Takashi Shiromoto, Naoyuki Himi, Feng Lu, Emi Maruyama-Nakamura, Kazuhiko Narita, Nobuhisa Iwachidou, Yoshiki Yagita, Osamu Miyamoto Motor map reorganization is believed to be one mechanism underlying rehabilitation-induced functional recovery. Although the ipsilesional secondary motor area has been known to reorganize motor maps and contribute to rehabilitation-induced functional recovery, it is unknown how the secondary motor area is reorganized by rehabilitative training. In the present study, using skilled forelimb reaching tasks, we investigated neural network remodeling in the rat rostral forelimb area (RFA) of the secondary motor area during 4weeks of rehabilitative training. Following photothrombotic stroke in the caudal forelimb area (CFA), rehabilitative training led to task-specific recovery and motor map reorganization in the RFA. A second injury to the RFA resulted in reappearance of motor deficits. Further, when both the CFA and RFA were destroyed simultaneously, rehabilitative training no longer improved task-specific recovery. In neural tracer studies, although rehabilitative training did not alter neural projection to the RFA from other brain areas, rehabilitative training increased neural projection from the RFA to the lower spinal cord, which innervates the muscles in the forelimb. Double retrograde tracer studies revealed that rehabilitative training inc...

Source: Neuroscience - October 27, 2016 Category: Neuroscience Source Type: research