Open AccessPrimary sensory and motor cortex activities during voluntary and passive ankle mobilization by the SHADE orthosis
Author(s) -
Pittaccio Simone,
Zappasodi Filippo,
Viscuso Stefano,
Mastrolilli Francesca,
Ercolani Matilde,
Passarelli Francesco,
Molteni Franco,
Besseghini Stefano,
Rossini Paolo Maria,
Tecchio Franca
Publication year - 2011
Publication title -
human brain mapping
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.005
H-Index - 191
eISSN - 1097-0193
pISSN - 1065-9471
DOI - 10.1002/hbm.20998
Subject(s) - ankle , isometric exercise , common peroneal nerve , physical medicine and rehabilitation , somatosensory system , stimulation , psychology , primary motor cortex , sensory system , motor cortex , medicine , transcranial magnetic stimulation , neuroscience , physical therapy , anatomy
Abstract This study investigates cortical involvement during ankle passive mobilization in healthy subjects, and is part of a pilot study on stroke patient rehabilitation. Magnetoencephalographic signals from the primary sensorimotor areas devoted to the lower limb were collected together with simultaneous electromyographic activities from tibialis anterior (TA). This was done bilaterally, on seven healthy subjects (aged 29 ± 7), during rest, left and right passive ankle dorsiflexion (imparted through the SHADE orthosis, O‐PM, or neuromuscular electrical stimulation, NMES‐PM), and during active isometric contraction (IC‐AM). The effects of focussing attention on ankle passive movements were considered. Primary sensory (FS S1 ) and motor (FS M1 ) area activities were discriminated by the Functional Source Separation algorithm. Only contralateral FS S1 was recruited by common peroneal nerve stimulation and only contralateral FS M1 displayed coherence with TA muscular activity. FS M1 showed higher power of gamma rhythms (33–90 Hz) than FS S1 . Both sources displayed higher beta (14–32 Hz) and gamma powers in the left than in the right hemisphere. Both sources displayed a bilateral reduction of beta power during IC‐AM with respect to rest. Only FS S1 beta band power reduced during O‐PM. No beta band modulation was observed of either source during NMES‐PM. Mutual FS S1 ‐FS M1 coherence in gamma2 band (61–90 Hz) showed a slight trend towards an increase when focussing attention during O‐PM. Somatosensory and motor counterparts of lower limb cortical representations were discriminated in both hemispheres. SHADE was effective in generating repeatable dorsiflexion and inducing primary sensory involvement similarly to voluntary movement. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.