Essentials: How to Control Your Sense of Pain & Pleasure

In this Huberman Lab Essentials discussion, Andrew Huberman, a professor of neurobiology and ophthalmology at Stanford School of Medicine, presents pain and pleasure as experiences that depend on both sensory detection and the brain’s interpretation. He describes them as opposite ends of a continuum: pleasure generally encourages approach and repetition, while pain generally encourages withdrawal. These tendencies are what he calls appetitive and aversive behaviors.

The skin supplies much of the incoming information. Huberman describes this largest organ as a protective barrier, a surface people decorate, and a sensory interface containing nerve endings responsive to touch, pressure, temperature, and chemicals. The sensory neurons’ cell bodies sit in dorsal root ganglia, collections of cells beside the spinal cord. In his account, branches extend outward to the skin and inward toward pathways communicating with the brain. Different neurons respond to different stimuli, but all communicate through electrical signals.

That shared electrical language creates the central explanatory problem: how does the brain distinguish an ice cube from heat or a habanero pepper? Huberman argues that the identity and interpretation of the signals matter. Experience contributes, but some responses require no prior learning; a child can withdraw from a flame on first contact. He highlights the somatosensory cortex and its body map, the homunculus, in which regions with dense sensory innervation receive disproportionately large representations. His examples include the lips, face, fingertips, feet, and genitals.

Two-point discrimination makes that uneven representation tangible. Huberman describes presenting two pen points about a centimeter apart to someone with closed eyes: on the top of the hand, the person can distinguish two simultaneous contacts, whereas the same spacing on the middle of the back may feel like one. The example connects the distribution of receptors to the precision of perception. It also sets up his broader argument that a physical stimulus alone does not fully explain the resulting experience.