Metacognitive Networks and Measures of Consciousness

Subjective measures of awareness rest on the assumption that conscious knowledge is knowledge that participants know they possess. Post-decision wagering, recently proposed as an objective measure of awareness, raised a new controversy on determining the properties that should characterize the objectivity of an awareness measure. Indeed, if the method appears objective in many aspects – it does not require introspection but rather lies on instinct, it does not affect conscious states, it can be learned unconsciously –, it also shares some characteristics with subjective measures – it involves metacognitive content and particularly, it represents a decision about a decision. The lack of consensus on this topic leaded us to develop a new approach based on a novel theoretical aspect, causality, and to consider a causally independent mechanism that would give an agent the capability to know what knowledge it possesses. In this framework, any measure that would not necessarily rely on such mechanism in a given experimental situation should be considered as objective. We support our claim with a computational model based on metacognitive networks, and present three simulation studies in which neural networks learn to wager on their own performance. Results demonstrate a good fit to human data, although depending on the situation, post-decision wagering is implemented either as an objective or as a subjective measure of network’s knowledge. We discuss implications of our results for defining the nature of subjective and objective measures, as well as for our understanding of consciousness.