Brain Neurorehabil.  2010 Sep;3(2):106-110. 10.12786/bn.2010.3.2.106.

Modulation of Motor Cortical Excitability Induced by Combined Visual Attention to Guide Finger Movement

• Joa KL
• Park JH
• Lee JJ
• Kim TH
• Jung HY

• KMID: 2308648
• DOI: http://doi.org/10.12786/bn.2010.3.2.106

Abstract

OBJECTIVE
To evaluate the effect of multiple sensory stimulation on cortical excitability by using transcranial magnetic stimulation (TMS). METHOD: Thirteen right handed young adults without neurological deficit were enrolled. Cortical excitability was tested by measuring recruitment of motor evoked potentials [recruitment curve (RC)], intracortical inhibition (ICI), and intracortical facilitation (ICF) at the abductor pollicis brevis of the dominant hand in two different conditions: (1) group A: active thumb and index finger pinch movement while observing the congruent finger movement in a screen with 0.2 Hz bell sound for 30 minutes, (2) group B: the same active finger movement in a dark screen with the same bell sound for 30 minutes. All of these procedures were done with a randomized crossover design.
RESULTS
The amplitude of MEP and the slope of all RC (140%,160% of the resting motor threshold) of group A showed increment after visually-guided finger movement and the level of ICI showed decrement after visually guided finger movement (p<0.05), but there was no change in the level of ICF (p>0.05) in group A. In group B, the amplitude of MEP and the levels of ICI, ICF showed no significant changes following finger movement with no visual guidance (p>0.05), but the slope of RC with 140% showed increment (p<0.05).
CONCLUSION
These findings suggest that cortical excitability can be enhanced by simple repetitive motor practice. The congruent sensori-motor stimulations lead to corresponding additional effect on cortical excitability, presumably by recruitment of remote motor neurons.

Keyword

cortical excitability; motor learning; multi-sensory stimulation; transcranial magnetic stimulation; visual attention