Fig. 1

Schematic of the neural circuitry [4], where each cortical level is specified by the perceptual states (S(i),V(i)) and their conjugate momenta (Ps(i),Pv(i)). The prediction error Ps(0) of incoming sensory data at the lowest level induces an inhibitory change in the perceptual momenta (Ps(1),Pv(1)). Subsequently, the prediction error propagates up the hierarchy