Functional magnetic resonance imaging analysis of attention to one's heartbeat.

摘要

OBJECTIVES: The convergence of a neural system for monitoring external stimuli with mechanisms that process somatic information leads to the hypothesis that the anterior parietal cortex may mediate attention to a specific internal visceral signal. METHODS: We measured regional brain activity through functional magnetic resonance imaging and directed subjects (6 men and 11 women) to attend to their own heartbeat, and to a heartbeat played on an external tape. RESULTS: Statistical parametric brain mapping revealed the importance of right (nondominant) parietal cortex to directing attention internally to one's visceral state and focusing on a specific body signal. CONCLUSIONS: The parietal activation may be taking advantage of monitoring skills typically utilized for vigilance to the external environment, in addition to working as a higher-level recognition system for signals emerging from the viscera. The finding suggests that the parietal cortex plays a central role in an interoceptive attention system that monitors bodily states.