The whole concept of the circadian rhythm is both equally exciting and fascinating. Basically stated; it’s the 24 hour cycle that the human body and any other biological process that can be found in plants and animals goes through.
The circadian clock as it is often times referred to dictates our sleep, eating, cognitive and behavioral patterns in a given time length. This natural rhythm is important to our health and well being on planet Earth, but having a healthy circadian rhythm is important to a quality life style.
Seasonal Affect Disorder for instance is thought to be caused by a lacking of sunlight during the later months of the year; which can lead to depression and a major change in mood.
Life operates on a schedule. Even when most people are sleeping in one part of the world, the sun is just rising in another part and people are entering the productive phase of the day. This natural process helps trigger when it’s time to sleep, eat, work or even play.
What’s very interesting about circadian rhythms is that although outside factors such as your environment can play a role; much of what controls your internal clock is based on genetics.
This system is brilliantly controlled by something called the “Master Clock” which is a complex set of nerve cells that are known as the suprachiasmatic nucleu. These cells sit in an area of the brain called the hypothalamus. This is located slightly above where the optic nerves for the eyes reside.
The location of the master clock is very important to understand. It does have a connection to how light is processed by the brain. As a result, when the outside environment is darker, the suprachiasmatic nucleu tells the body to produce more melatonin; A hormone that contributes to sleep.
Likewise, being in a well lit environment will trigger the opposite effect. This is also why you can play an important role in your own circadian rhythm and develop a better schedule by keeping a consistent bed time, turning off the television when you go to sleep and making an effort to rise at the same time every morning.
The issue with something such as seasonal depression is that the days get shorter and the human body wants to go into a hibernation mode. This is problematic as people still need to continue about their daily lives as though it was any other time during the year.
Circadian Rhythm Sleep Disorders
Sleep disorders may also affect the circadian rhythm, by interrupting it’s natural pattern. One of the more common of these disorders is Delayed Sleep Phase Disorder, which delays the actual point of falling asleep until very early in the morning. This causes the body to want to rest through the morning hours when people normally wake up.
The opposite is Advanced Sleep Phase Disorder which is where a person will fall asleep in the evening hours relatively early and then awakes early in the morning; such as 2AM – 4AM and cannot get back to sleep.
A healthy sleep cycle can be had, but does require work on the person’s part. Usually, with Delayed Sleep Disorder a patient will force themselves to climb into bed an hour or two earlier than normal. This does not come to fruition yet, but over several weeks the body may adjust and finally get the idea that it’s actually time to enter sleep mode.
With Advanced Sleep Phase Disorder a patient will force themselves to stay awake a little longer each night to adjust the sleep cycle. Finally, another method of treatment that may be incorporated is a careful dosage of light therapy to adjust the circadian rhythm.