Fig. 2

fMRI paradigm. We conducted four functional imaging runs. In each trial, participants were exposed to one body photograph presented on the screen, followed by either the “comparison task” or the “weight estimation task”. In the comparison task, participants were asked to compare their own body shape with the presented body photograph, and to rate their own subjective anxiety level in response to the photograph using four buttons on an MRI-compatible button pad (1 = “calm”, 2 = “somewhat calm”, 3 = “slightly anxious”, and 4 = “anxious”). In the weight estimation task, participants were required to objectively estimate the weight of the body in the photograph, selecting one of four weight categories (35, 55, 65, or 80 kg) using the 4-button pad. Each trial started by indicating the task with presentation of “comparison task” or “weight estimation task” for 2.5 s, followed by the task response, lasting for 5 s. Each trial ended with a fixation cross that continued to be presented during a 7.5 s inter-trial interval