Definition

• Circadian rhythm is the natural, internal process that regulates the sleep-wake cycle and repeats approximately every 24 hours. It is driven by a biological clock and influenced by environmental cues like light and darkness.

• The circadian rhythm controls the other clocks of the body like the heart

The Suprachiasmatic Nucleus

• The superchiasmatic nuclei lies in the hypothalamus of our brain

• The suprachiasmatic nucleus is considered the clock of our mind

• It receives direct input from the eyes via the retinohypothalamic tract to respond to light.

Our ipRGC gets activated when we are expose to light, they contain there melanopsin which is a protein type that helps it to sense light, they are activated through the rods and cones at the first, melanopsins cause the retinohypothalamic tract to be active that helps the suprachiasmatic nuclei