Scientists Identify Possible Brain Mechanism That May Act as Switch for Chronic Pain

Chronic pain may not just linger-it may be actively switched on by the brain.

A new study published in the Journal of Neuroscience has identified a hidden brain circuit that appears to decide whether short-term pain fades away or turns into long-lasting suffering. Researchers from the University of Colorado Boulder found that a small region deep in the brain, called the caudal granular insular cortex (CGIC), plays a central role in sustaining chronic pain.

Unlike acute pain—which acts as a protective signal after injury—chronic pain persists long after healing, often becoming a debilitating condition. This study suggests that the CGIC functions as a kind of “decision-maker,” determining whether pain signals should continue.

Using advanced techniques such as chemogenetics, researchers were able to selectively activate or inactivate specific neurons in animal models. They discovered that the CGIC is not essential for immediate pain perception but is crucial for maintaining pain over time. When this circuit was activated, it amplified signals from the somatosensory cortex to the spinal cord, effectively instructing the body to keep feeling pain—even in response to harmless touch, a phenomenon known as allodynia.

Strikingly, when scientists silenced this pathway shortly after injury, chronic pain never developed. Even more promising, turning off the circuit in animals already experiencing chronic pain caused the pain to disappear.

Such insights could pave the way for targeted therapies that go beyond traditional painkillers, including opioids, which carry risks of addiction and side effects.

While more research is needed before applying these findings to humans, the study opens the door to innovative treatments—ranging from targeted brain infusions to brain-machine interfaces—that could one day offer lasting relief for millions living with chronic pain.

REFERENCE: Jayson B. Ball, Maggie R. Finch, Jeremy A. Taylor, Zachariah Z. Smith, Igor Rafael Correia Rocha, Suzanne M. Green-Fulgham, Ethan B. Rowe, Joseph M. Dragavon, Connor J. McNulty, Renee A. Dreher, Imaad I. Siddique, Gavin Davis, Andrew M. Tan, Michael V. Baratta, Daniel S. Barth, Linda R. Watkins. Caudal Granular Insular Cortex to Somatosensory Cortex I: A Critical Pathway for the Transition of Acute to Chronic Pain. The Journal of Neuroscience, 2026; 46 (5): e1306252025 DOI: 10.1523/JNEUROSCI.1306-25.2025