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The present study explores whether endogenous attention can modulate body perception. A modified version of the Posner paradigm was used to direct participants' attention toward the appearance of distinct body images, which differed only in detailed idiosyncratic features: one's own and another person's hands. Hand stimuli were preceded by symbolic cues that predicted their identity with high probability, which made it possible to compare the processing of expected (valid) and unexpected (invalid) targets. Results revealed that endogenous attention influenced the processing of participants' own hands by speeding participants' responses to valid in contrast to invalid trials. Crucially, no validity effect was found for the hands of another person. These findings r cannot be explained in terms of perceptual familiarity, since an optimization of the processing for both familiar and unfamiliar faces by symbolic cues was observed. In light of these results, it is suggested that participants are able to anticipate particular stimuli within the same perceptual category as long as these stimuli appear to are able to anticipate particular stimuli within the same perceptual category as long as these stimuli appear to be remarkably distinct to them, which is probably the case for particular faces and their own bodies, in contrast to other people's bodies.

High-density electroencephalographic recordings were used to investigate the level of analysis at which attentional expectations modulate the processing of specific stimuli from the same perceptual category but differentiated in terms of a particular non-perceptual feature: body ownership. We used a task in which colour cues predicted whether a picture of a hand stimulus belonged to the participant or to somebody else. Participants were instructed to respond whether the target was a left or a right hand. Results revealed that the ERP pattern depended on stimulus ownership and attention orienting, which influenced the visual processing of own and someone else's hands differentially. Larger amplitude for others' than for own hands was shown at the N1 deflection (at the right hemisphere). Attentional effects were found at the P2 and P3 potentials. The P2 reflected an interaction between stimulus ownership and attentional orienting, due to a larger validity effect for others' hands. At the P3 level, the data showed a significant validity effect only for self-hand stimuli. In sum, our results suggest that (1) differences as a function of stimulus ownership can be detected at early levels of stimulus processing; (2) endogenous attention can be directed to exemplars within the same category, hand stimuli in this case; (3) the effects of attention are modulated by ownership.