Suprachiasmatic Nucleus (SCN), Your Internal Clock

Timing of Sleep and wakefulness: The suprachiasmatic nucleus (SCN), is the master’s clock in the brain, having many important functions in the body. Located in the anterior hypothalamus, it’s profoundly affected by light. Light is probably the most important environmental cue that sets the timing of sleep. Light exposure is linked to inhibition of melatonin secretion. In the evening melatonin increases as daylight diminishes. Other forms of light can in essence mimic daylight and inhibit the drive to sleep at night, (i.e. cell phone light). Light hits the retina, which sends signals to the SCN to turn off. Melatonin activates the SCN on 2 receptors, affecting sleep. The suprachiasmatic nucleus also provides signals to peripheral areas of the body, via the autonomic nervous system and hormonal release. This complex coordinated effort is referred to as peripheral circadian oscillation stimulation. This explains why some chronic ailments tend to be worse at night and why some medications are absorbed best at certain times over a 24- hour period. #bettersleep #neuroscience #insomniac #sleepmedicine #fitnessandhealth