A role for visceral feedback and interoception in feelings-of-knowing

•Are feeling-of-knowing (FOK) judgments shaped by visceral bodily signals?•Changes in cardiovascular and facial muscle activity were recorded during FOK task.•Previously studied face cues elicited an increased heart rate relative to novel faces.•The link between cardiovascular changes and FOK ratings was moderated by interoception.•Previously studied face cues were associated with an EMG marker of positive affect. Guided by the framework that autonomic feedback shapes emotional experience and other feeling states, we asked whether feeling-of-knowing (FOK) judgments may be influenced by visceral information through interoception. Participants performed a FOK task for previously studied face-name pairs while changes in cardiovascular and facial muscle activity were recorded. Previously studied face cues for which the corresponding name could not be recalled elicited an increased cardiac rate relative to novel face cues. Critically, the relationship between this pattern of cardiovascular activity and FOK ratings was moderated by interoception, such that for individuals with high interoceptive sensitivity, relative increases in cardiac rate for old items were associated with larger corresponding differences in FOK. Consistent with a link between familiarity and positive affect, we also found that old items elicited less frowning, as reflected in muscle activity recorded from the corrugator muscle. These results provide psychophysiological evidence that visceral signals contribute to experiential metamemory processes.