Self-awareness, the capacity to regard oneself as an object of awareness, remains a puzzle addressed by religion, philosophy, and science. This review examines the neurocognitive mechanisms behind self-awareness, describing it as a multidimensional, emergent property that manifests at different levels of cognitive complexity, framed within predictive coding theory. It discusses how self-awareness is altered in neuropsychiatric conditions and evaluates alternative frameworks for understanding it in both health and psychopathology. The article identifies gaps in current knowledge and suggests directions for future research.
Self-awareness—the capacity to make oneself the object of one's own attention—has clinical relevance, and understanding its neurochemical basis may clarify causes of and treatments for psychopathological conditions. This article reviews how psychedelics influence self-awareness by affecting brain networks such as the default-mode and salience networks, and neurotransmitters. Within a predictive-coding framework, it examines effects on interoception, body ownership, agency, metacognition, emotional regulation, and autobiographical memory. Improved emotional regulation and autobiographical memory have been observed with psychedelic use, suggesting changes in higher-order self-awareness, modulated by relaxed priors and enhanced cognitive flexibility. Bodily self-awareness alterations are less consistent, potentially varying with dose, acute versus long-term effects, and clinical conditions.
People with Alzheimer's disease show a range of changes in consciousness, including reduced awareness of cognitive deficits, diminished self-awareness, and impaired introspection, which appear early and worsen as the disease progresses. These awareness impairments are linked to brain damage in areas that overlap with proposed neural correlates of consciousness. The authors argue that recognizing Alzheimer's disease as a disorder of consciousness is overdue and important for understanding patients' lived experience and improving care.