Stimulating stimulation: can we improve motor recovery following stroke using repetitive transcranial magnetic stimulation?

Background: Ongoing impairment of the upper limb is common after stroke, despite neurorehabilitation. This impairment has a significant impact on an individual's activity and participation in life roles. It is essential to explore new ways to optimize motor recovery. Objectives: This narrative review describes repetitive transcranial magnetic stimulation (rTMS), which is a non-invasive electrophysical technique, currently being investigated in the laboratory setting. It considers the role rTMS might play in the future of stroke rehabilitation. Major findings: In the research setting, rTMS can be used to safely increase the excitability of descending motor pathways that innervate the paretic hand. When applied to the primary motor cortex (M1) of the lesioned or non-lesioned hemisphere, rTMS can temporarily improve motor behaviour of the paretic hand. Preliminary research supports the use of rTMS in conjunction with therapy, but repeated sessions are probably required to induce longer lasting changes that have a functionally meaningful effect for the patient. Conclusions: The use of rTMS to improve motor recovery following stroke appears promising, especially to prime the brain for a better response to subsequent therapy. Further research is required before the use of rTMS can move from the laboratory to the clinic.