Laughter on the BrainThe physiological study of laughter has its own name -- gelotology. And we know that certain parts of the brain are responsible for certain human functions. For example, emotional responses are the function of the brain's largest region, the frontal lobe. But researchers have learned that the production of laughter is involved with various regions of the brain. While the relationship between laughter and the brain is not fully understood, researchers are making some progress.
- The left side of the cortex (the layer of cells that covers the entire surface of the forebrain) analyzed the words and structure of the joke.
- The brain's large frontal lobe, which is involved in social emotional responses, became very active.
- The right hemisphere of the cortex carried out the intellectual analysis required to "get" the joke.
- Brainwave activity then spread to the sensory processing area of the occipital lobe (the area on the back of the head that contains the cells that process visual signals).
- Stimulation of the motor sections evoked physical responses to the joke.
The Limbic System
Structures in the brain's limbic system, which controls many essential human behaviors, also contribute to the production of laughter.
While the structures in this highly developed part of the brain interconnect, research has shown that the amygdala, a small almond-shaped structure deep inside the brain, and the hippocampus, a tiny, seahorse-shaped structure, seem to be the main areas involved with emotions. The amygdala connects with the hippocampus as well as the medial dorsal nucleus of the thalamus. These connections enable it to play an important role in the mediation and control of major activities like friendship, love and affection and on the expression of mood. The hypothalamus, particularly its median part, has been identified as a major contributor to the production of loud, uncontrollable laughter.