Nature exposure induces hypoalgesia by acting on nociception-related neural processing

Abstract

Nature exposure has numerous psychological benefits, and previous findings suggest that exposure to nature reduces self-reported acute pain. Given the multi-faceted and subjective quality of pain and methodological limitations of prior research, it is unclear whether the evidence indicates genuine hypoalgesia or results from domain-general effects and subjective reporting biases. This preregistered functional neuroimaging study aimed to identify how nature exposure modulates nociception-related and domain-general brain responses to acute pain. We compared the self-reported and neural responses of healthy neurotypical participants (N = 49) receiving painful electrical shocks while exposed to virtual nature or to closely matched urban and indoor control settings. Replicating existing behavioral evidence, pain was reported to be lower during exposure to the natural compared to the urban or indoor control settings. Crucially, machine-learning-based multi-voxel signatures of pain demonstrated that this subjective hypoalgesia was associated with reductions in nociception-related rather than domain-general cognitive-emotional neural pain processing. Preregistered region-of-interest analyses corroborated these results, highlighting reduced activation of areas connected to lower-level somatosensory aspects of pain processing (such as the thalamus, secondary somatosensory cortex, and posterior insula). These findings demonstrate that nature exposure results in genuine hypoalgesia and that neural changes in lower-level nociceptive pain processing predominantly underpin this effect. This advances our understanding of how nature may be used as a non-pharmacological pain treatment. That this hypoalgesia was achieved with brief and easy-to-administer virtual nature exposure has important practical implications and opens novel avenues for research on the precise mechanisms by which nature impacts our mind and brain.