laughter(redirected from Ha ha ha)
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Alternative medicine See Laughter club, Laughter therapy, Laughter yoga
Neurology Spasmodic and largely involuntary expirations often accompanied by inarticulate vocalisations, generally evoked by mirth
Physiology Laughter increases blood flow to the brain and activates neural networks—e.g., nucleus accumbens (NAcc) and amygdala. Functional MRI data suggests that the increase in blood flow to NAcc evoked by extreme humour is similar to that triggered by monetary gain or use of some addictive drugs; a key symptom of depression is the lack of a sense of reward from previously rewarding activities—e.g., humour
Psychiatry Laughter is regarded as the most effective coping skill for anxiety-panic disorders and may temporarily alleviate the symptoms of anxiety and depression
A series of inarticulate sounds produced as an expression of emotion, usually happiness or mirth. The role of humor and laughter in promoting a positive attitude and health and in preventing the progress of some diseases has been documented esp. when it is combined with proven medical therapies.
Laughter without cause, occurring in certain psychoses, esp. schizophrenia.
Uncontrolled laughter (occasionally accompanied by, or alternating with, uncontrolled crying), caused by pseudobulbar lesions of the brain. These lesions may result from lacunar strokes, multiple sclerosis, anoxic brain injury, and other forms of brain injury.