diving reflex

American  

noun

Physiology.

1. a reflex of humans, other mammals, reptiles, and birds, triggered by immersion in cold water, that slows the heart rate and diverts blood flow to the brain, heart, and lungs: serves to conserve oxygen until breathing resumes and to delay potential brain damage.

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Etymology

Origin of diving reflex

First recorded in 1975–80

Example Sentences

This activates the diving reflex, which slows the heart rate and redirects blood away from the periphery of the body, toward the heart and other vital organs.

From Washington Post • Sep. 7, 2021

When people plunge into water, they respond with the so-called diving reflex: The heart rate slows and blood vessels constrict as a way to shunt blood to vital organs.

From Seattle Times • May 4, 2018

All mammals have a diving reflex, but marine mammals like seals have a particularly strong one.

From New York Times • Apr. 19, 2018

This distinct slowing of the heart is one component of the larger diving reflex that diverts blood to essential organs while submerged.

From Textbooks • Jun. 19, 2013

The reason, says Nemiroff, is a combination of coldness, which lowers the body's need for oxygen, and an old mammalian response known as the diving reflex.

From Time Magazine Archive