Covert singing in anticipatory auditory imagery.

To date, several fMRI studies reveal activation in motor planning areas during musical auditory imagery. We addressed whether such activations may give rise to peripheral motor activity, termed subvocalization or covert singing, using surface electromyography. Sensors placed on extrinsic laryngeal muscles, facial muscles, and a control site on the bicep measured muscle activity during auditory imagery that preceded singing, as well as during the completion of a visual imagery task. Greater activation was found in laryngeal and lip muscles for auditory than for visual imagery tasks, whereas no differences across tasks were found for other sensors. Furthermore, less accurate singers exhibited greater laryngeal activity during auditory imagery than did more accurate singers. This suggests that subvocalization may be used as a strategy to facilitate auditory imagery, which appears to be degraded in inaccurate singers. Taken together, these results suggest that subvocalization may play a role in anticipatory auditory imagery, and possibly as a way of supplementing motor associations with auditory imagery.