Brain Area Controls Timing of Sleep, Wakefulness, Temperature
What is the suprachiasmatic nucleus (SCN)?
Discover what happens if the SCN becomes damaged and what other signals may become important.
A Word on Circadian Rhythms
There are multiple internal processes that are externally influenced by our environment.
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The termcircadiandescribes the approximately 24-hour cycles that are generated independently of these external influences.
What Is the Suprachiasmatic Nucleus of the Brain’s Hypothalamus?
The suprachiasmatic nucleus is located in a forward region of the brain called thehypothalamus.
It contains a group of nerve cells (or neurons) that control your body’s circadian rhythm.
Within the hypothalamus sits the SCN, the body’s central pacemaker (or master clock).
Circadian rhythm sleep disorders can occur when the synchrony between the body and the external environment is lost.
Patterns of sleep and wakefulness may no longer align with societal norms.
These conditions include:
These conditions occur for multiple reasons.
People who are totally blind, completely lacking the perception of light, can develop Non-24.
Trauma, stroke, or tumors may also impact the SCN and cause its dysfunction.
The timing of hormone release, metabolism, and other processes may become disturbed.
There is some early research that suggests this may contribute to various disease states.
Other signals for timing may become important.
In the blind, a low dose of melatonin in the evening may be necessary.
Alternatively, the use of Hetlioz may be indicated.
Ramsey, KM and Bass, J.
Animal models for disorders of chronobiology: cell and tissue, inPrinciples and Practices of Sleep Medicine.
Edited by Kryger MH, Roth T, Dement WC.
St. Louis, Missouri, Elsevier Saunders, 2011, pp.
