Supramarginal activity in interoceptive attention tasks.

Interoceptive (feelings from inside organs) attention/awareness (IAA) is a body-related aspect of cognition that pursues homeostasis by detecting afferent signals, and there are practices aimed at focusing one's attention and awareness towards such feelings inside one's own body. There is a claim that these practices improve health which is one reason that neural correlates of such practices and IAA in general have been investigated in previous imaging studies. In several of these studies which used subjects with no or limited experience in IAA practices there was a report of supramarginal (SM) activity during IAA tasks, but the role of SM in IAA remain unclear. We first investigated if we could find similar results in novices, and if this activity is sensitive to the designated body part in the IAA task. We further investigated if these regions would be similarly recruited in subjects with extensive experience of IAA tasks while comparing results with a group of age and gender matched novices. Results in the novices replicated that of previous studies, and we showed this is the same for IAA tasks regarding two different parts of the body. Group comparison results showed opposite profiles of SM activation for the two groups; novices showed activation and the experts showed deactivation of the SM. The results suggest that novices recruit SM during IAA possibly due to lack of experience in those tasks but this could be alleviated for performing IAA as illustrated by activation profile in experts.