Fig. 4.

Belief propagation and extrinsic connectivity. This schematic illustrates a putative mapping between expectations that are updated during belief updating and recurrent interactions within the cortico-basal ganglia-thalamic loops. This figure is based upon the functional neuroanatomy described in (Jahanshahi et al., 2015), which assigns motor updates to motor and premotor cortex projecting to the putamen; associative loops to prefrontal cortical projections to the caudate and limbic loops to projections to the ventral striatum. The correspondence between the message passing implicit in belief propagation and the organisation of these loops is remarkable; even down to the level of the sign (excitatory or inhibitory) of the neuronal connections. The striatum (caudate and putamen) and the subthalamic nucleus (STN) receive inputs from many cortical and subcortical areas. The internal segment of the globus pallidus (GPi) constitutes the main output nucleus from the basal ganglia. The basal ganglia are not only connected to motor areas (motor cortex, supplementary motor cortex, premotor cortex, cingulate motor area and frontal eye fields) but also have connections with associative cortical areas. The basal ganglia nuclei have topologically organized motor, associative and limbic territories; the posterior putamen is engaged in sensorimotor function, while the anterior putamen (or caudate) and the ventral striatum are involved in associative (cognitive) and limbic (motivation and emotion) functions (Jahanshahi et al., 2015).