On a confusion about there being two types of consciousness.
Liad Mudrik, Nathan Faivre, Michael Pitts, Aaron Schurger
Trends in Cognitive Sciences December 17, 2025 DOI: 10.1016/j.tics.2025.11.012 (opens in new tab) via PubMed
Summary
AI-generated from the abstractA major controversy in consciousness science divides sensory and cognitive theories. Reexamining Block's 1995 distinction between phenomenal consciousness (P) and access consciousness (A), the authors argue that P and A are not two different types of consciousness but two necessary conditions for consciousness. This conceptual shift helps resolve unresolved questions about neural mechanisms, functions of consciousness, and its relationship with attention. The proposal motivates selective unification across different classes of theories.
Study at a glance
| Characteristics | Theoretical or philosophical paper Peer reviewed |
|---|---|
| Keywords | Access consciousness Awareness Phenomenal consciousness Theories of consciousness |
| Citations | 5 |
| Key finding | Proposes that phenomenal and access consciousness are necessary conditions for consciousness, not distinct types, and that this shift resolves theoretical controversies and enables selective unification of theories. |
Abstract
Progress in the scientific study of consciousness has been impeded by several fundamental controversies. One pertains to a major divide between theories: sensory versus cognitive. Here, we argue that the key to resolving this controversy is to reevaluate the conceptual distinction proposed by Block in 1995 between phenomenal consciousness (P) and access consciousness (A). We propose that P and A should not be understood as two different types of consciousness, but as two necessary conditions for consciousness. We illustrate how this conceptual shift allows making substantial progress in answering several unresolved questions, such as the neural mechanisms and functions of consciousness, and the relationship between consciousness and attention. Our proposal motivates a selective unification across these different classes of theories.