Abstract: PURPOSE: Previous studies have demonstrated that visual size perception is highly context-dependent and involves multiple neural computations. However, it is heretofore unknown whether visual size perception can be modulated by self - referential information .
METHODS: The present study aimed to probe this issue by adopting self-referential stimuli (self-face and self-associated cartoon face), for use in a size discrimination paradigm. Famous faces were also employed to ensure that the modulation of self-face on size perception, if observed, reflect a genuine “self-effect” rather than a familiarity effect.
RESULTS: We found that self-face was perceived as significantly larger than other faces of the same size, and this size overestimation effect was not observed when a famous face was compared with other faces. Moreover, such illusion effect could extend to a cartoon face repeatedly associated with one's own face and further exert contextual influences on visual size perception of other objects.
CONCLUSIONS: These findings together highlight the role of self-awareness in visual size perception, and point to a special mechanism of size perception tuned to self-referential information.

Key words: visual size illusion, self-face, self-associated