Circadian Rhythm: the master of sleep
A human being roughly spends one-third of its lifespan being asleep. To the super-productive people among us it may seem ludicrous. No kidding, there are people who often comment on how sleeping is a wastage of time and one can make better use of that extra time we spend on sleeping and so on and on. Well, we don’t know about them but according to experts, sleep is an indispensable aspect of human existence. Ayurveda, the great Indian medical system considers sleep as an essential pillar responsible for life and death. Life cannot survive without sleep. It helps to process information into memories, promotes better metabolism, provides relaxation to muscles and internal organs and what not — without sleep there is no survival. But why do we fall asleep and then wake up at a particular time every day? A (snoozed) alarm clock might be required to get up on time. But surely there is no alarm clock to tell us when we need to fall asleep. Turns out, there actually is an alarm clock deep inside that brain that keeps track of habits and helps us function according to our daily routine.
Circadian rhythm is the biological clock that help us function in a regular, organised manner. We typically sleep eat and defecate almost at a particular time every day. Circadian rhythm is to be thanked for this phenomenon as it signals the body to carry out such tasks around a particular time every day. A single cycle of this rhythm is completed in 24 hours. Thereby synchronising our activities with that of the day. Commonly it is termed as the biological clock of each and every human being. The act of falling asleep at a particular time every day is a product of this circadian rhythm that signals the brain to release hormones and enzymes that promote exhaustion and thus prepares the body for sleep. However, circadian rhythm is not an isolated entity that functions on its own. It is sensitive to the habit of an individual and is also further altered by external cues such as light and temperature.
The condition of an altered circadian rhythm is called circadian rhythm sleep disorder (CRSD). This phenomenon disrupts the normal biological clock bringing irregularities in sleep cycle. Human beings’ increased proximity with the virtual world is seen as a common cause behind disrupted sleeping patterns. Any kind of digital screen emits a blue light. This blue light tricks the eyes and deceives the brain into believing that there is daylight remaining. It receives the light as a signal to remain awake and thus hinders with sleep cycle. Another common aspect of disrupted circadian rhythm can be spotted in travel. Travelling into a different time zone especially one that is a lot different than the native time zone disturbs the circadian rhythm. The phenomenon is known as jetlag whereby the body fails to match up with the lost or gained time in within a 24-hour cycle.
So, the next time you wake up early on a holiday don’t blame fate! It’s just your biological clock who failed to recognise it as a holiday.
