An adjunction hypothesis between qualia and reports

Quantum-like Qualia hypothesis: from quantum cognition to quantum perception

To arbitrate theories of consciousness, scientists need to understand mathematical structures of quality of consciousness, or qualia. The dominant view regards qualia as points in a dimensional space. This view implicitly assumes that qualia can be measured without any effect on them. This contrasts with intuitions and empirical findings to show that by means of internal attention qualia can change when they are measured. What is a proper mathematical structure for entities that are affected by the act of measurement? Here we propose the mathematical structure used in quantum theory, in which we consider qualia as "observables" (i.e., entities that can, in principle, be observed), sensory inputs and internal attention as "states" that specify the context that a measurement takes place, and "measurement outcomes" with probabilities that qualia observables take particular values. Based on this mathematical structure, the Quantum-like Qualia (QQ) hypothesis proposes that qualia observables interact with the world, as if through an interface of sensory inputs and internal attention. We argue that this qualia-interface-world scheme has the same mathematical structure as observables-states-environment in quantum theory. Moreover, within this structure, the concept of a "measurement instrument" in quantum theory can precisely model how measurements affect qualia observables and states. We argue that QQ naturally explains known properties of qualia and predicts that qualia are sometimes indeterminate. Such predictions can be empirically determined by the presence of order effects or violations of Bell inequalities. Confirmation of such predictions substantiates our overarching claim that the mathematical structure of QQ will offer novel insights into the nature of consciousness.

Comparing color qualia structures through a similarity task in young children versus adults

Examination of the subjective qualitative aspects of an experience, or "qualia" in short, is a fundamental and core aspect of consciousness research. How can we characterize the particular quality of redness, i.e. a red quale? Based on a recent proposal of the structural characterization of qualia, which did not rely on verbal descriptions, we developed a task that obtained pairwise similarity judgments at four graded levels, with easy and intuitive visual interfaces designed to engage young children. We examined color qualia structures in children (3 to 12-y-old in Japan and 6 to 8-y-old in China) and compared these with those of Japanese adults. Approximately half of the assessed 3-y-old children completed the experiment via our touch panel device version of the task and had reliable responses. Despite known developmental and/or cultural effects of color term usage, we found that color qualia structures were quite similar across the age groups and cultures. Our finding supports the view that color qualia structures emerge early. We also observed age-related differences in the evaluations of some color pairs, which implied subtle changes in the structures behind color experience.

Consciousness Under the Spotlight: The Problem of Measuring Subjective Experience

The study of consciousness is considered by many one of the most difficult contemporary scientific endeavors and confronts several methodological and theoretical challenges. A central issue that makes the study of consciousness so challenging is that, while the rest of science is concerned with problems that can be verified from a "third person" view (i.e., objectively), the study of consciousness deals with the phenomenon of subjective experience, only accessible from a "first person" view. In the present article, we review early (starting during the late 19th century) and later efforts on measuring consciousness and its absence, focusing on the two main approaches used by researchers within the field: objective (i.e., performance based) and subjective (i.e., report based) measures of awareness. In addition, we compare the advantages and disadvantages of both types of awareness measures, evaluate them according to different methodological considerations, and discuss, among other issues, the possibility of comparing them by transforming them to a common sensitivity measure (d'). Finally, we explore several new approaches-such as Bayesian models to support the absence of awareness or new machine-learning based decoding models-as well as future challenges-such as measuring the qualia, the qualitative contents of awareness-in consciousness research.

Towards a structural turn in consciousness science

Recent activities in virtually all fields engaged in consciousness studies indicate early signs of a structural turn, where verbal descriptions or simple formalisations of conscious experiences are replaced by structural tools, most notably mathematical spaces. My goal here is to offer three comments that, in my opinion, are essential to avoid misunderstandings in these developments early on. These comments concern metaphysical premises of structural approaches, the viability of structure-preserving mappings, and the question of what a structure of conscious experience is in the first place. I will also explain what, in my opinion, are the great promises of structural methodologies and how they might impact consciousness science at large.