Dopamine, Affordance and Active Inference
Figure 5
This figure summarizes the results of simulations under normal levels of dopamine (using a log precision of four for all prediction errors).
The conditional predictions and expectations are shown as functions of time over 128 time bins, each modeling 64 ms of time. The upper left panel shows the conditional predictions (colored lines) and prediction errors (red lines) based upon the expected in states on the upper right. In this panel and throughout, the grey areas denote 90% Bayesian confidence intervals. The inferred speed of itinerant cycling among affordance states corresponds to the first of the hidden causes at the second level (left middle panel). These hidden causes are a softmax function of their associated hidden states (right middle panel). The blue lines encode a sequential context, while the green lines encode the converse (random) context. The switching in these conditional expectations occurs after sufficient sensory evidence has accumulated following a reversal of the presentation order. The lower left panel shows the trajectory (dotted lines) in an extrinsic frame of reference, in relation to the cue locations (green circles), while the lower right panel shows action in terms of horizontal and vertical angular forces causing these movements.