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Definition of Suprachiasmatic Nucleus


Updated February 18, 2014

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Definition: The suprachiasmatic nucleus is located in a region of the brain called the hypothalamus, and contains a group of nerve cells (neurons) that control your body's biological clock (or circadian rhythm). This circadian rhythm controls many physiological and behavioral rhythms, including the sleep-wake cycle.

The suprachiasmatic nucleus lies in a shallow impression of the optic chiasm, and is highly influenced by the input of light.

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