This study explores the neural systems supporting interoceptive awareness, focusing on how the brain processes internal bodily signals and relates them to subjective emotional experiences. Using functional magnetic resonance imaging (fMRI), researchers found that the right anterior insula, somatomotor cortex, and cingulate cortex are involved in interoceptive tasks, such as detecting one's own heartbeat. Neural activity in the right anterior insula predicted accuracy in heartbeat detection, and local gray matter volume in this region correlated with both interoceptive accuracy and subjective ratings of visceral awareness. Additionally, negative emotional experiences were linked to interoceptive accuracy across subjects. The study also examined the relationship between interoceptive sensitivity and subjective emotional experiences, finding that anxiety symptoms correlated with interoceptive accuracy and activity in the right anterior insula. These findings support the idea that the right anterior insula plays a key role in representing visceral responses accessible to awareness, which underlies subjective feeling states. The study further used voxel-based morphometry to test the relationship between brain structure and interoceptive awareness, finding that gray matter volume in the right anterior insula, orbitofrontal cortex, and midline cerebellum correlated with interoceptive accuracy. These results suggest that the right anterior insula is critical in mediating awareness of interoceptive information contributing to emotional feeling states. The study also discusses the role of the insula in integrating interoceptive and external information, and how it may support a contextual "second-order representation of self." The findings highlight the importance of the anterior insula cortex in supporting interoceptive attention and explicit awareness of bodily processes, as well as emotional feeling states. The study concludes that the right anterior insula is a key region in the brain that supports interoceptive awareness and contributes to subjective emotional experiences.This study explores the neural systems supporting interoceptive awareness, focusing on how the brain processes internal bodily signals and relates them to subjective emotional experiences. Using functional magnetic resonance imaging (fMRI), researchers found that the right anterior insula, somatomotor cortex, and cingulate cortex are involved in interoceptive tasks, such as detecting one's own heartbeat. Neural activity in the right anterior insula predicted accuracy in heartbeat detection, and local gray matter volume in this region correlated with both interoceptive accuracy and subjective ratings of visceral awareness. Additionally, negative emotional experiences were linked to interoceptive accuracy across subjects. The study also examined the relationship between interoceptive sensitivity and subjective emotional experiences, finding that anxiety symptoms correlated with interoceptive accuracy and activity in the right anterior insula. These findings support the idea that the right anterior insula plays a key role in representing visceral responses accessible to awareness, which underlies subjective feeling states. The study further used voxel-based morphometry to test the relationship between brain structure and interoceptive awareness, finding that gray matter volume in the right anterior insula, orbitofrontal cortex, and midline cerebellum correlated with interoceptive accuracy. These results suggest that the right anterior insula is critical in mediating awareness of interoceptive information contributing to emotional feeling states. The study also discusses the role of the insula in integrating interoceptive and external information, and how it may support a contextual "second-order representation of self." The findings highlight the importance of the anterior insula cortex in supporting interoceptive attention and explicit awareness of bodily processes, as well as emotional feeling states. The study concludes that the right anterior insula is a key region in the brain that supports interoceptive awareness and contributes to subjective emotional experiences.