Perceptual awareness and active inference

Perceptual awareness depends upon the way in which we engage with our sensorium. This notion is central to active
inference, a theoretical framework that treats perception and action as inferential processes. This variational perspective
on cognition formalizes the notion of perception as hypothesis testing and treats actions as experiments that are designed
(in part) to gather evidence for or against alternative hypotheses. The common treatment of perception and action affords a
useful interpretation of certain perceptual phenomena whose active component is often not acknowledged. In this article,
we start by considering Troxler fading – the dissipation of a peripheral percept during maintenance of fixation, and its
recovery during free (saccadic) exploration. This offers an important example of the failure to maintain a percept without
actively interrogating a visual scene. We argue that this may be understood in terms of the accumulation of uncertainty
about a hypothesized stimulus when free exploration is disrupted by experimental instructions or pathology. Once we take
this view, we can generalize the idea of using bodily (oculomotor) action to resolve uncertainty to include the use of mental
(attentional) actions for the same purpose. This affords a useful way to think about binocular rivalry paradigms, in which
perceptual changes need not be associated with an overt movement.