Predictive Brain Talk Series

13.08.2026

From sensation to structure: inferring the body in space.

Speaker:
Valeria Peviani (Universitätsklinikum Hamburg Eppendorf)

Host:
Predictive Brain Department (RUB)

Venue:
MB 7/159 or Zoom: https://ruhr-uni-bochum.zoom-x.de/j/68193768258?pwd=PIr8naXEpVt1aXGLUY9g0MSFpjPyg2.1

Starting time:
2:00 PM

Abstract:
The body is our primary interface with the world. It follows that the way we perceive it shapes how we sense and interact with our environment. Yet, people systematically misjudge its size, geometry, and configuration. One striking example is the hand, whose fingers are consistently perceived as shorter and wider than they really are. These distortions are often interpreted as evidence for distorted internal representations of the body. Intuitively, however, this seems difficult to reconcile with our remarkable ability to interact so effectively with the world.

In this talk, I will argue for a different perspective. Drawing on behavioral and computational work, I will show that body perception biases are not arbitrary errors, but lawful consequences of the computations the brain performs to estimate the body. First, I will discuss evidence that these distortions extend beyond perceptual judgments, influencing action and relating to the perception of the objects we interact with. Second, I will present a probabilistic computational framework showing how such biases can emerge naturally from estimating body configuration under uncertainty, even when accurate information about the body is available. Finally, I will consider body perception as part of a continuous perception–action cycle, in which sensory evidence, prior expectations, and movement dynamically interact to update body estimates over time.

Together, these findings support a view of the body not as a fixed internal representation, but as the result of a dynamic inferential process through which sensation becomes structure.