, 2009) The

visual stimuli in the experimental condition

, 2009). The

visual stimuli in the experimental conditions (Supplemental Information), presented through video goggles, consisted of short movies showing a back view of the virtual body filmed from an elevated position (Lenggenhager et al., 2009) (body conditions) being stroked by a sphere positioned at the end of a rod and moving vertically along the midline of the virtual person’s back (Figure 1A). The video during the control conditions only showed the moving rod and stimulator without the person’s body (no-body conditions; Ibrutinib clinical trial Figure 1B). A custom-built robotic device (Figures 1C and 1D) allowed us to control the trajectory of tactile stimulation of the participant’s back in both body and control conditions (using the same movement profile). This trajectory either matched (synchronous) or did not match (asynchronous) the applied tactile stimuli to the visually Thiazovivin nmr displayed position of the virtual rod (Supplemental Information). Thus, we precisely controlled the spatial and temporal aspects of the stimulation sphere’s movement during scanning within and across participants (Supplemental Information). Participants performed the MBD task under four different conditions according to a 2 × 2 factorial design with Object (body; no-body) and Stroking (synchronous; asynchronous)

as main factors. Immediately after the fMRI session (before the acquisition of the anatomical Thymidine kinase images), participants completed a six-items questionnaire (Supplemental Information) to measure the experienced direction

of the first-person perspective and illusory self-identification with the virtual body (Lenggenhager et al., 2007) (Table S1). To define the structures that are involved in abnormal states of first-person perspective and self-location, we also studied a large group of neurological patients suffering from OBEs (Blanke et al., 2002 and Blanke et al., 2004; Heydrich et al., 2011; Devinsky et al., 1989 and Maillard et al., 2004). We performed quantitative lesion analysis (Rorden et al., 2007a) and compared the distribution of brain lesions in nine OBE-patients with those of eight other patients showing complex hallucinations involving people or faces, but without abnormal self-location, self-identification, or first-person perspective (control group; Table S3). This allowed us to determine the anatomical sub-regions of maximal lesion overlap and to perform statistical comparisons contrasting the lesions of OBE and control patients (voxel-based lesion symptom mapping; VLSM) (Bates et al., 2003a). Based on previous data in patients with OBEs, we predicted to find maximal involvement of the TPJ. Based on these clinical data, we also predicted that the BOLD response of this structure in healthy subjects would reflect changes in self-location that are dependent on the experimental factors Stroking and Object.

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