Opinion

How do you feel? Interoception: the sense of the physiological condition of the body

Abstract

As humans, we perceive feelings from our bodies that relate our state of well-being, our energy and stress levels, our mood and disposition. How do we have these feelings? What neural processes do they represent? Recent functional anatomical work has detailed an afferent neural system in primates and in humans that represents all aspects of the physiological condition of the physical body. This system constitutes a representation of 'the material me', and might provide a foundation for subjective feelings, emotion and self-awareness.

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  1. sensory system organization

    • sensory systems in vertebrates: general overview

      • somatosensory systems

        • emotion and the human brain

          Acknowledgements

          I thank E. Rolls and L. Watkins for their comments on the manuscript, and many collaborators and friends for constructive discussions. Work in the author's laboratory is supported by the National Institutes of Health and the Barrow Neurological Foundation.

          Author information

          Affiliations

          1. A. D. (Bud) Craig is at the Atkinson Pain Research Laboratory, Division of Neurosurgery, Barrow Neurological Institute, Phoenix, Arizona 85013, USA.bcraig@chw.edu

            • A. D. Craig

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          Glossary

          AIR HUNGER

          Hypercapnia with mechanically restricted ventilation.

          ERGORECEPTION

          Afferent activity relating tissue energy and metabolic needs.

          EXERCISE PRESSOR REFLEX

          Increased blood pressure and heart rate caused by activity in small-diameter afferents from muscle.

          FIRST PAIN

          Sharp, pricking pain associated with rapidly conducting Aδ-fibres.

          LABELLED LINES

          Anatomically and physiologically distinct neurons that are specifically associated with particular sensations.

          NEUROPATHIC PAIN

          Intractable pain associated with damage to the peripheral or central nervous system.

          SECOND PAIN

          Dull, burning pain associated with slowly conducting C-fibres.

          TRIADIC ARRANGEMENT

          Ultrastructural contacts between an afferent terminal, a relay cell dendrite and a GABA-containing presynaptic dendrite that is characteristic of high-fidelity transmission in sensory relay nuclei.