A laugh that prompts you to cry out, "That tickles!" activates different brain areas than a laugh not provoked by tickling, a new study from Germany suggests.
In the study, about 30 men and women in their 20s were tickled for science — they had their feet tickled by a friend or partner while their brains were scanned in a functional magnetic resonance imaging (fMRI) machine. Separately, participants were asked to produce a laugh voluntarily (not in response to a joke) inside an fMRI machine, which measures blood flow to different areas of the brain to provide a real-time map of brain activity.
Both ticklish laughter and voluntary laughter activated the Rolandic operculum brain region, which is located in the primary sensory-motor cortex and is involved in movements of the face; both laughter types were also linked to activity in brain regions involved in vocal emotional reactions, such as crying.
For the rest of the story: Brain Area for Ticklish Laughter Found