OUT-OF-BODY, OUT-OF-TIME. ABNORMAL UNITY OF BODY AND SELF IN SPACE AND TIME
Under normal conditions, human subjects experience the self within the limits of the physical body and the limits of the present time. This unified experience of the self in space and time has been challenged by philosophers and physicists. The spatial unity between self and body has also been challenged by a well defined group of experiences called “autoscopic phenomena” (AP), during which subjects have the impression of seeing a second own body in extrapersonal space. Yet, with respect to the three main forms of AP — autoscopic hallucination, heautoscopy, and out-of-body experience — previous studies have concentrated on describing the spatial unity between self and body while neglecting to analyze the temporal unity of self and body. Here we describe several AP-cases with an altered experience of age or time for one’s own body or self. In some AP-cases the second own body was seen as being younger or older than the subject’s actual body. We show that the second own body is experienced as if “coming from another time” although the observing self is experienced in the present time. Other AP-subjects reported a feeling of timelessness of the observing self without any age difference between the subjects’ actual and illusory body. We argue that these differences in age or time suggest that the temporal experience of one’s own body and self is altered in these subjects. Collectively, these data suggest that AP may be associated not only with abnormal sensations with respect to spatial unity, but also with respect to temporal unity. Moreover, we found that out-of-body experiences were associated with feelings of timelessness and no age differences between self and body and that autoscopic hallucinations and heautoscopy were associated with age differences between self and body but not with feelings of timelessness. We conjecture that out-of-body experiences are characterized by disembodiment not only in space but also in time. For autoscopic hallucinations and heautoscopy our findings suggest that the spatial displacement between self and body (without disembodiment) is accompanied by a temporal displacement of the body to a different time period than the present. We discuss these abnormal experiences of the bodily self in time and space and propose their potential functional and anatomical mechanisms.