Cognition Research Today is a free monthly online journal that collates and summarizes the latest research about Cognition, including details on psychology, neuroscience, memory, brain theory. | ||||||||
|
Motor imagery in blind subjects: the influence of the previous visual experience.Imbiriba LA, Rodrigues EC, Magalhães J, Vargas CD Laboratory of Biomechanics, School of Physical Education, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil. Mental simulation of movements has been widely used to infer about representational aspects of action. On a daily basis, motor planning and execution depends crucially both upon vision and kinesthesia. What if the former is lost? In this study we investigate the physiological changes induced during a mental simulation task in subjects with early and late onset blindness, analyzing simultaneously stabilometric (body sway), electromyographic (EMG, lateral gastrocnemius) and eletrocardiographic (ECG) signals. Subjects were asked to stand up on a force platform and instructed either to: rest during 20s; count mentally from 1 to 15; imagine themselves executing a bilateral plantar flexion 15 times and execute the same movement 15 times. Discriminant analysis was employed to have access to the differences in the groups with respect to heart rate variability (HRV), EMG and body sway measurements for each condition. We found an overall correct classification of 100 and 90.9%, respectively, for the stabilometric parameters and HRV. This result was found only for the mental simulation task (p<0.05), being absent for resting, counting and executing. Previous studies have shown that motor simulation in a kinesthetic mode strongly associates with somatic and autonomic changes. In late blind subjects, however, movement simulation would tend to unfold with the use of both visual and kinesthetic representations. Thus, our results suggest that early and late blind subjects make use of distinct body representations during motor imagery. Published 8 May 2006 in Neurosci Lett, 400(1): 181-5.
© 2005-2008 Cognition Research Today. All Rights Reserved. |
| ||||||
