The Mind from Within: Visceral Roots of Human Cognition

Humans think and act not only with the brain but also with the heart, lungs, gut, and other viscera—such as the bladder—long regarded as primarily vegetative. Converging evidence implicates visceral organs in memory, consciousness, volitional action, and social cognition. Expanding on this evidence, we advance a deep embodiment theory in which visceral states and their conscious perception (interoception) systematically shape cognition and behavior. We review mechanistic links implicating cardiac-cycle phase and baroreceptor activity in perception and social behavior; respiration-locked neural dynamics in attention and learning; and gastrointestinal rhythms and vagal afferents in affect and decision-making. We assess emerging methods, including ingestible sensors that record gastrointestinal signals in situ during emotional and cognitive tasks, and virtual reality stimuli linked to cardiac and respiratory rhythms. We detail the implications of deep embodiment for economic decision-making, clinical interventions (e.g., organ transplantation), and environmental exposures (e.g., air quality). Finally, we contrast deep embodiment with brain-reductionist and “shallow” embodiment accounts, propose protocols to assess cognition across visceral modalities, and outline implications for AI systems that incorporate visceral-like signals for state estimation and adaptive control—arguing that viscera are active components of cognition rather than background noise.