Exploring the Role of the Central Thermoregulatory System in Implicit and Explicit Body Ownership: A Cold Stimulation Study

Body ownership, influenced by both implicit and explicit mechanisms, is defined as the experience of owning one’s own body in a coherent unity. Research has demonstrated that both levels arise from the integration of multisensory modalities, including internal and external bodily signals, and that their disruption can alter body ownership. Among these internal signals, skin temperature plays a key role in shaping body ownership, a connection that is repeatedly shown by studies that highlighted how changes in the sense of body ownership were often accompanied by alterations in skin temperature. Skin temperature, as part of the peripheral thermoregulatory system, participates in the bidirectional communication between external thermal changes and the regulation of core body temperature. While several studies have focused on the relationship between peripheral thermoregulatory responses and body ownership, the role of central thermoregulation remains largely unexplored. Thus, the present study aimed to investigate whether variations in implicit and explicit body ownership are associated with systemic changes in the thermoregulatory system. To study their relationship, 23 healthy participants completed an Implicit Association Test (IAT), a questionnaire on explicit body ownership, and a cold exposure task. Participants immersed their hands in 10°C water for three minutes while skin temperature was monitored via infrared thermography. Post-cold exposure thermal recovery patterns were used to classify individuals as faster or slower rewarmers, reflecting homeostatic efficiency. Results revealed that higher explicit body ownership was associated with more efficient thermal recovery, suggesting a link with central thermoregulatory processes. It is shown that explicit body ownership is more closely tied to homeostatic regulation, supporting the notion of a “protective body map” proposed by de Vignemont (2017), in which the body serves mainly as a defensive boundary aimed at maintaining survival. On the contrary, no such association was found for implicit body ownership, supporting the idea that explicit and implicit body ownership rely on distinct mechanisms.