Stroke and spinal cord injuries can severely impair motor functions, and understanding how to promote recovery is a critical challenge. While damaged neurons in the brain and spinal cord have limited ability to regenerate, the brain can form or strengthen alternative neural pathways involving uninjured parts of the brain, enabling functional recovery. Such reorganization of pathways in the brain is called neural plasticity, and identifying the involved pathways and understanding their functions can aid in developing more effective rehabilitation strategies.
Previous research has shown that when one side of the corticospinal tract-;a major pathway that carries movement signals from the brain to the spinal cord-;is damaged, the activity in the motor cortex on the opposite side of the brain increases. This has led to questions about whether this increased activity helps or hinders recovery, and the precise role of these pathways has been unclear. In a study published in Nature Communications , researchers from WPI-ASHBi, Kyoto University and National Institute of Physiological Sciences conducted experiments in macaque monkeys to explore how this change in neuronal activity affects recovery from spinal cord injury.
To manipulate neural activities in both motor cortices, viral vectors were injected into targeted brain areas to block communication between the left and right motor cortices via drug administration, the effect of which was reversible. This allowed the researchers to o.