Swallow-related cerebral cortical activity maps are not specific to deglutition

Cortical representation of swallow-related motor tasks has not been systema tically investigated. In this study, we elucidated and compared these corti cal representations to those of volitional swallow using block-trial and si ngle-trial methods. Fourteen volunteers were studied by functional magnetic resonance imaging. Cortical activation during both swallowing and swallow- related motor tasks that can be performed independent of swallowing, such a s jaw clenching, lip pursing, and tongue rolling, was found in four general areas: the anterior cingulate, motor/premotor cortex, insula, and occipita l/parietal region corresponding to Brodmann's areas 7, 19, and 31. Regions of activity, volume of activated voxels, and increases in signal intensity were found to be similar between volitional swallow and swallow-related mot or tasks. These findings, using both block-trial and single-trial technique s, suggest that cerebral cortical regions activated during swallowing may n ot be specific to deglutitive function.