title: Training based on mirror visual feedback influences transcallosal communication.
abstract: Mirror visual feedback (MVF) therapy has been demonstrated to be successful in neurorehabilitation, probably inducing neuroplasticity changes in the primary motor cortex (M1). However, it is not known whether MVF training influences the hemispheric balance between the M1s. This topic is of extreme relevance when MVF training is applied to stroke rehabilitation, as the competitive interaction between the two hemispheres induces abnormal interhemispheric inhibition (IHI) that weakens motor function in stroke patients. In the present study, we evaluated, in a group of healthy subjects, the effect of motor training and MVF training on the excitability of the two M1s and the IHI between M1s. The IHI from the 'active' M1 to the opposite M1 (where 'active' means the M1 contralateral to the moving hand in the motor training and the M1 of the seen hand in the MVF training) increased, after training, in both the experimental conditions. Only after motor training did we observe an increase in the excitability of the active M1. Our findings show that training based on MVF may influence the excitability of the transcallosal pathway and support its use in disorders where abnormal IHI is a potential target, such as stroke, where an imbalance between the affected and unaffected M1s has been documented.
authors.affiliation: Department of Experimental Medicine, Section of Human Physiology and Centro Polifunzionale di Scienze Motorie, University of Genoa, Genoa, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Avanzino
authors.forename: Alessia
authors.initials: A
authors.lastname: Raffo
authors.forename: Elisa
authors.initials: E
authors.lastname: Pelosin
authors.forename: Carla
authors.initials: C
authors.lastname: Ogliastro
authors.forename: Roberta
authors.initials: R
authors.lastname: Marchese
authors.forename: Piero
authors.initials: P
authors.lastname: Ruggeri
authors.forename: Giovanni
authors.initials: G
authors.lastname: Abbruzzese
mesh_terms: D000328:Adult; D003337:Corpus Callosum / Q000502:physiology*; D004576:Electromyography; D056228:Feedback, Sensory / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D009044:Motor Cortex / Q000502:physiology*; D009433:Neural Inhibition / Q000502:physiology*; D009434:Neural Pathways / Q000502:physiology; D000071939:Stroke Rehabilitation; D050781:Transcranial Magnetic Stimulation; D055815:Young Adult
keywords: interhemispheric inhibition; mirror visual feedback; training; transcranial magnetic stimulation