Individuals lack the capacity to accurately detect emotional piloerection

Piloerection (e.g., goosebumps) is an essential thermoregulatory and social signalling mechanism in non-human animals. While humans also experience piloerection--often being perceived as an indicator of profound emotional experiences--its comparatively less effective role in thermoregulation and communication might influence our capacity to monitor its occurrence. We present three studies (total N = 617) demonstrating participants general inability to detect their own piloerection events and their lack of awareness that piloerection occurs with a similar frequency on multiple anatomical locations. Participants over-reported piloerection events with only 31.8% coinciding with observable piloerection, a bias unrelated to piloerection intensity, anatomical location, heart rate variability, or interoceptive awareness. We also discovered a self-report bias for the forearm, contradicting the observation that piloerection occurs with equal frequency on multiple anatomical locations. Finally, there was low correspondence between self-reports of being "emotionally moved" and observed piloerection. These counterintuitive findings not only highlight a disconnect between an obvious physiological response and our capacity for self-monitoring, but they underscore a fascinating divergence between human and non-human species. While piloerection is vital in non-human organisms, the connection between piloerection and psychological experience in humans may be less significant than previously assumed, possibly due to its diminished evolutionary relevance. Statement of ImpactThis research reveals a striking dissociation between an obvious physiological response-- piloerection--and human capacity for self-perception. While this highlights the limitations of relying on self-report measures, it also underscores an important divergence between humans and non-human species. We propose that the relation between piloerection and psychological experience in humans is less pronounced than in other species, potentially due to its diminished role in human evolution.