The effect of visual and auditory enhancements on excitability of the primary motor cortex during motor imagery: a pilot study.

The effect of visual and auditory enhancements of finger movement on corticospinal excitability during motor imagery (MI) was investigated using the transcranial magnetic stimulation technique. Motor-evoked potentials were elicited from the abductor digit minimi muscle during MI with auditory, visual and, auditory and visual information, and no information. Ten healthy participants were instructed to imagine repetitive abduction and adduction of the fifth finger. After each condition, the extent of vividness of MI was rated using a visual analogue scale. The results showed that the mean visual analogue scale score and motor-evoked potentials amplitude for the auditory and visual condition were higher than those of other conditions, indicating an enhanced excitability of the primary motor cortex with a clearer image of motor action during MI.