brainstem

American  

[breyn-stem] / ˈbreɪnˌstɛm /

Or brain stem

noun

1. the portion of the brain that is continuous with the spinal cord and comprises the medulla oblongata, pons, midbrain, and parts of the hypothalamus, functioning in the control of reflexes and such essential internal mechanisms as respiration and heartbeat.

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brainstem British  

/ ˈbreɪnˌstɛm /

noun

1. the stalklike part of the brain consisting of the medulla oblongata, the midbrain, and the pons Varolii

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brainstem Scientific  

/ brān′stĕm′ /

1. The part of the vertebrate brain located at the base of the brain and made up of the medulla oblongata, pons, and midbrain. The brainstem controls and regulates vital body functions, including respiration, heart rate, and blood pressure.

2. See also reticular formation

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Etymology

Origin of brainstem

First recorded in 1875–80; brain + stem ¹

Example Sentences

What especially piqued Ruyle’s interest in the nTS is that it’s the first area of the brainstem to receive input from the large nerves that relay information about cardiorespiratory function.

From Salon • Feb. 6, 2025

Working with week-old zebrafish larva, researchers at Weill Cornell Medicine and colleagues decoded how the connections formed by a network of neurons in the brainstem guide the fishes' gaze.

From Science Daily • Nov. 22, 2024

Axial symptoms, which have not received extensive study in relation to DBS, improved with stimulation of tracts connected to the supplementary motor cortex and brainstem.

From Science Daily • Jun. 4, 2024

I didn’t articulate any of this at the time, but a previously unknown, murky appendage in my brainstem lifted its head and howled disagreement.

From Salon • May 27, 2024

Capping the brainstem is the R-complex, the seat of aggression, ritual, territoriality and social hierarchy, which evolved hundreds of millions of years ago in our reptilian ancestors.

From "Cosmos" by Carl Sagan