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Dr Rikaz Sheriff Certificate in Medical Education

Outline of Lecture

• Introduction to Laughter• Laughter – A Medical Perspective• Laughter – How your body does it• Laughter – Research & Practice• Laughter – The Dark Side

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Introduction to Laughter

• Laughter is an audible expression or the appearance of happiness, or an inward feeling of joy (laughing on the inside).

• It may ensue (as a physiological reaction) from jokes, tickling or other stimuli. It is in most cases a very pleasant sensation.

• Laughter is found among various animals such as rats and chimpanzees, as well as in humans.

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Laughter – A Medical Perspective• It is a part of human behavior regulated by the

brain, helping humans clarify their intentions in social interaction and providing an emotional context to conversations & can be contagious!

• Laughter is anatomically caused by the epiglottis constricting the larynx.

• The study of humor and laughter, and its psychological and physiological effects on the human body, is called gelotology.

• Inability to laugh out loud is termed aphonogelia.05/03/23 4Dr Rikaz Sheriff - Certificate in Medical

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Laughter – How your body does it• Ventromedial prefrontal cortex• Limbic System• American Medical Association

in 1984 “…So while purely emotional responses such as laughter are mediated by subcortical structures, especially the hypothalamus, and are stereotyped, the cerebral cortex can modulate or suppress them.“

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Laughter – Research & Practice• A positive link has been found between laughter

and a healthy function of blood vessels with laughter causing such tissues that form using the inner lining of blood vessels, the endothelium, to dilate or expand such to increase blood flow.

• Laughter Yoga is a type of relaxation exercise.• Professor Norman Cousins - “I made the joyous

discovery that ten minutes of genuine belly laughter had an anesthetic effect and would give me at least two hours of pain-free sleep”

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Laughter – The Dark Side

• Death may result from several pathologies that deviate from benign laughter.

• Infarction of the pons and medulla oblongata in the brain may cause pathological laughter.

• The incurable neurological disease Kuru is also known as the laughing sickness due to the pathologic bursts of laughter people would display when afflicted with the disease.

• Excessive laughter can lead to cardiac arrest!

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References

• http://en.wikipedia.org/wiki/Laughter• http://en.wikipedia.org/wiki/

Ventromedial_prefrontal_cortex• http://en.wikipedia.org/wiki/Norman_Cousins• http://en.wikipedia.org/wiki/Death_from_laughter• http://www.ncbi.nlm.nih.gov/pubmed/19251872

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