The effect of afferent training on long-term neuroplastic changes in the human cerebral cortex

Abstract

In the present study we explored the effect of long-term intervention protocol (3 w, 1 h/day) with sensory stimulation on neuroplastic changes in the human motor cortex. Interventions consisted of repetitive activation of afferent pathways of the right abductor policies brevis (APB) muscle with tendon vibration (TV) and transcutaneous electrical nerve stimulation (TENS). The representations of the hand (APB, ADM) and forearm (FCR, ECR) muscles were mapped using transcranial magnetic stimulation (TMS) before and after the 3 weeks of sensory intervention (TV and TENS) groups or after similar periods of daily active training of the APB or rest (control). Our observations showed a significant increase in motor cortical representation of all the four muscles (as measured by changes in the map size) for the TENS group. No such effects were observed in the tendon vibration group, active training group or the control group.