The importance of light stimulus
We tend to overlook the negative effects of our circadian rhythm, especially on our ability to stay focused when we are not well-rested. Daylight has been indicated as the most important factor in regulating the human circadian rhythm.
An unbalanced rhythm affects us in strange ways; often, we are so busy that it gets neglected or even unaware of its effects.
- Temperature(biology)
- Activity
- Food
- Hormones (Melatonin, cortisol)
They all May affect the mammalian circadian clock as well.
However, suppose one changes the light schedule. In that case, regardless of the change in activity or any other stimulus, the human circadian pacemaker will often follow the light stimulus and not be affected by the presence or absence of the other “zeitgebers” (time-givers).
The pathway from external light to the pacemaker in the brain has received much recent attention from researchers. Originally, it was thought that only rods and cones in the retina could send light signals to the circadian clock in the brain. However, mice that lack rods or cones can still be entrained to light and dark signals.
