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Why do people throw their heads back when experiencing ecstasy, agony, laughter, grief and surprise?
Chris Daniel
Glan Conwy, Colwyn Bay, UK
Laughter is a complex social and physical response to something amusing, but it can also be associated with other emotions, such as shock or embarrassment.
A laugh is a series of (usually) involuntary rhythmical contractions of the diaphragm and other respiratory muscles in the abdomen and chest resulting in the rapid expulsion of air from the lungs, along with vocalisations from the larynx. Resistance to this airflow can be minimised by the mouth being opened wide and the head being tilted back, a position that opens the airways by moving the tongue and other soft tissues away from the back of the throat, similar to that done in first aid in order to facilitate resuscitation.
An additional effect of the head rocking back is to straighten the airway. Air flows more efficiently through a straight channel than one with bends.
This head position is similar to that adopted by other animals when they need to communicate loud and socially important messages. Picture the howling wolf, the bellowing stag and the roaring lion. All extend their necks to straighten the airway, so that the strength and volume of the call is maximised and the sound carries as far as possible.
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The wolf, stag and lion all extend their necks to straighten the airway so the strength and volume of their call is maximised
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The equivalent of laughter among apes such as chimpanzees is important in social bonding and reducing tension. In humans, it plays a similar role. A shared joke communicates acceptance and a feeling of mutual trust and cohesion within a group.
Clive McGavin
Horrabridge, Devon, UK
When Wolfgang Amadeus Mozart wrote the opera Cosi Fan Tutte with the priest and librettist Lorenzo Da Ponte, the leading soprano role of Fiordiligi was taken by Da Ponte’s mistress, Adriana Ferrarese del Bene. She was known for her wide vocal range. Mozart noted that when going for high notes, she threw her head back, and for low notes, she lowered her chin to her chest.
In one of the opera’s arias, the exacting Come scoglio, Mozart makes the soprano alternate from high notes to low notes, displaying the full vocal range. Thus it may be that extending the head backwards allows the larynx to produce higher and louder vocalisation.
Andrew Kadir-Buxton
Hatfield, Hertfordshire, UK
Lemmy Kilmister of Motörhead sang with his head back to increase the distance that his voice was heard. It was probably used to get other people to join in before the advent of the mobile phone.
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