About this Journal Submit a Manuscript Table of Contents
BioMed Research International
Volume 2013 (2013), Article ID 634891, 9 pages
http://dx.doi.org/10.1155/2013/634891
Research Article

Electrophysiological Correlates of the Threshold to Detection of Passive Motion: An Investigation in Professional Volleyball Athletes with and without Atrophy of the Infraspinatus Muscle

1Neuromuscular Research Laboratory, National Institute of Traumatology and Orthopaedics (INTO), Avenida Brasil 500, 20940-070 Rio de Janeiro, RJ, Brazil
2Brazilian Volleyball Confederation, Shopping Città America Avenida das Américas 700, Bloco 7, Barra da Tijuca, 22640-100 Rio de Janeiro, RJ, Brazil
3Biomedical Engineering Program, Centre of Technology, Federal University of Rio de Janeiro, Avenida Horácio Macedo 2030, Bloco H, Sala 327, Cidade Universitária, 21941-901 Rio de Janeiro, RJ, Brazil
4Brain Mapping and Sensorimotor Integration Laboratory, Institute of Psychiatry, Federal University of Rio de Janeiro, Avenida Venceslau Brás 71, Botafogo, 22290-140 Rio de Janeiro, RJ, Brazil
5Institute of Applied Neuroscience (IAN), Rua Pacheco Leão 704, 25 Jardim Botânico, 22460-030 Rio de Janeiro, RJ, Brazil

Received 16 August 2012; Revised 21 November 2012; Accepted 2 December 2012

Academic Editor: Elvira Gonzalez De Mejia

Copyright © 2013 José Inácio Salles et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The goal of the present study is to compare the electrophysiological correlates of the threshold to detection of passive motion (TTDPM) among three groups: healthy individuals (control group), professional volleyball athletes with atrophy of the infraspinatus muscle on the dominant side, and athletes with no shoulder pathologies. More specifically, the study aims at assessing the effects of infraspinatus muscle atrophy on the cortical representation of the TTDPM. A proprioception testing device (PTD) was used to measure the TTDPM. The device passively moved the shoulder and participants were instructed to respond as soon as movement was detected (TTDPM) by pressing a button switch. Response latency was established as the delay between the stimulus (movement) and the response (button press). Electroencephalographic (EEG) and electromyographic (EMG) activities were recorded simultaneously. An analysis of variance (ANOVA) and subsequent post hoc tests indicated a significant difference in latency between the group of athletes without the atrophy when compared both to the group of athletes with the atrophy and to the control group. Furthermore, distinct patterns of cortical activity were observed in the three experimental groups. The results suggest that systematically trained motor abilities, as well as the atrophy of the infraspinatus muscle, change the cortical representation of the different stages of proprioceptive information processing and, ultimately, the cortical representation of the TTDPM.