Face perception is often studied as the processing of information contained within individual faces. Yet, faces are rarely encountered in isolation, and their spatial relationships may play an important role in how we perceive and represent them. In this talk, I will introduce the “Fat-Face" illusion, a striking perceptual phenomenon in which two identical faces, when presented vertically, appear to differ in size: the lower face is consistently perceived as larger than the upper face. This illusion suggests that the visual system uses spatial position to infer the relative proximity of faces, with lower faces perceived as closer and consequently larger.

Using this illusion as an experimental paradigm, I will present a series of studies examining how social information influences perceived facial proximity and how these perceptual processes change from childhood to adulthood. Our findings suggest that spatial relationships are not merely contextual features of face perception but may be integral to how faces are represented. Moreover, the prolonged developmental trajectory of these effects points to a potential role of accumulating social and perceptual experience in shaping our representations of faces. Together, these studies highlight the dynamic interplay between spatial perception, social information, and experience in face processing.