Although theories of emotion have long noted the importance of afferent feedback from the autonomic nervous system in generating feelings, there is a growing appreciation that this feedback may also play a role in shaping cognitive experiences. At present, little is known about its functional role in memory judgments. In the current study, we examined whether afferent cardiovascular feedback shapes recognition-memory decisions and experiences when previously encountered faces are being discriminated from novel ones. To investigate this possibility, we capitalized on the natural variation in baroreceptor mediated cardiovascular feedback that is associated with the cardiac cycle, synchronizing the brief presentation of memory probes during retrieval with individual heartbeats. In Experiments 1 and 2, we found that faces presented during cardiac systole (i.e., when visceral feedback is maximal) were more likely endorsed as "old" than those presented during cardiac diastole (i.e., when afferent feedback is minimal). This pattern was present for targets and lures, and held for faces with fearful or neutral expressions. Combining this manipulation with a remember/know procedure, Experiment 3 showed that the influence of afferent cardiovascular feedback is specific to trials on which participants report a feeling of familiarity without successful recollection of pertinent contextual detail. By revealing an influence of baroreceptor mediated cardiovascular feedback on familiarity, the current findings identify the functional role of a specific autonomic channel, previously implicated in emotion, in feeling states that pertain to memory experience.
