Suprachiasmatic nucleus

Suprachiasmatic Nucleus (SCN) is a tiny region of the brain in the hypothalamus, situated directly above the optic chiasm. It is responsible for controlling circadian rhythms. The neuronal and hormonal activities it generates regulate many different body functions in a 24-hour cycle, using around 20,000 neurons.

Structure

The SCN is situated in the anterior hypothalamus, just above the optic chiasm, from which it takes its name. It is a bilateral structure, with each side containing approximately 10,000 neurons. The SCN is one of the most densely vascularized areas of the brain, and has a high metabolic activity.

Function

The SCN controls circadian rhythms in mammals. These rhythms are daily cycles of physiological processes that are regulated by the SCN. The most well-known circadian rhythm is the sleep-wake cycle, but others include body temperature, feeding times, and hormone production.

Clinical significance

Disruption of the SCN can lead to a variety of sleep and mood disorders, including insomnia, depression, and bipolar disorder. It has also been implicated in the aging process and in the development of cancer.

Research

Research on the SCN has focused on understanding its role in sleep disorders and mood disorders, as well as its potential role in aging and cancer. This research has the potential to lead to new treatments for these conditions.

See also

• Circadian rhythm
• Hypothalamus
• Optic chiasm

Suprachiasmatic_nucleus

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  Suprachiasmatic nucleus
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  Suprachiasmatic nucleus
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  Circadian rhythm labeled