Overview
- The review by Fausto Caruana and Sophie K. Scott, published June 23, 2026, in Trends in Neurosciences analyzes intracranial electrical stimulation reports and animal studies to argue for two distinct laughter networks.
- The spontaneous network includes the pregenual anterior cingulate, nucleus accumbens, and temporal pole and produces uncontrollable laughter that patients report as euphoric or mirthful.
- A separate volitional network—centred on the rolandic operculum, globus pallidus, and presupplementary motor area—drives the motor acts of conversational or polite laughter without positive emotion.
- The authors note overlap between the spontaneous network and the brain's pain-modulation systems, suggesting a biological route for laughter's short-term analgesic effects and potential therapeutic uses.
- Coverage stresses key limits: the synthesis relies mainly on opportunistic stimulation cases in awake epilepsy patients and animal work, so causal, controlled experiments are needed to test mechanisms and clinical applications.