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area postrema

a highly vascularized region of the brain located in the basal wall of the lateral ventricle. Brain capillaries in this area form a relatively permeable region of the blood–brain barrier, enabling the passage of toxic substances to the underlying chemoreceptor trigger zone, which elicits a vomiting response.

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Psychology term of the day

November 16th 2024

Doppler effect

Doppler effect

the apparent increase or decrease in wavelength or frequency observed when a source of electromagnetic radiation or sound approaches or recedes from the observer or listener, producing a change in hue or pitch. The total Doppler effect may result from motion of the source, observer, or medium (such as a sound wave). [Christian Andreas Doppler (1803–1853), Austrian mathematician]