The Laughing Species

Natural History, Dec, 2000 by Robert R. Provine

Other disorders in which laughter may be a symptom include manganese poisoning, Wilson disease (a disorder caused by a recessive gene that leads to the accumulation of copper in the brain), some types of epilepsy, Alzheimer disease and the somewhat similar Pick disease, Rett disorder (a condition affecting only gifts, in whom a common symptom is solitary, nocturnal laughter), Angelman disorder (a genetic condition whose unfortunate victims were once dubbed "happy puppets"), Williams disorder (a genetic but not hereditary illness in which frequent laughter is part of an abnormally gregarious nature), and some kinds of schizophrenia. The symptom is also sometimes seen in lobotomy patients and other sufferers of frontal lobe damage and in victims of amyotrophic lateral sclerosis (Lou Gehrig's disease) and multiple sclerosis. In many of these pathologies, the laughter is not connected with feelings of mirth--the patient is as baffled and horrified as everyone else is when the errant brain causes him or her to bark out an emotionless sound. Curiously, laughter is not a symptom of Tourette's disorder, otherwise known for tics and vocal outbursts.

Laughter may be primed through the use of drugs such as marijuana or laughing gas (nitrous oxide), which can make things seem funnier, or stimulated by group conditions favoring mass hysteria or religious fervor. Some aspects of a person's style or frequency of laughing, if not his or her taste in humor, may even be inherited, as in the case of the "giggle twins"--female identical twins who were separated at birth, raised by relatively sober families, and reunited forty years later. Both had a similar predisposition to laughter.

One of the pleasures of my quest to understand laughter has been to escape from my windowless neurophysiology laboratory to seek laughing in all its contexts--bars, zoos, comedy clubs, acting classes, neurology clinics, city sidewalks, operas, TV laugh tracks, Pentecostal services, tickle wars. The study of laughter requires a catch-as-catch-can interdisciplinary approach and entails grappling with some of science's knottiest problems--the interrelationship of nature and nurture and the evolution of speech, language, and social behavior. Above all, studying laughter provides new insights into what it means to be and act human.

Although his doctoral dissertation on the development of electrical activity in the spinal chord of the chick embryo was followed by research on more than thirty other animal species, Robert R. Provine ("The Laughing Species") eventually decided "it was time to get out of the lab and apply my techniques and findings to human behavior." The result, based on an investigation of everything from personal ads in newspapers to laugh boxes (Provine owns a hundred of them), was Laughter: A Scientific Investigation (Viking Press, 2000). The book includes "Ten Tips for Increasing Laughter" but none for suppressing it ("It's easy to kill laughter, and many people and enterprises already have mastered this more modest art"). A professor of psychology at the University of Maryland, Baltimore County, Provine plans to continue his research on laughter and tickling and to investigate the behavior of self-replicating machines.