Every living creature on this Earth (that has a lifespan longer than a few days) will have an internal clock guiding their every waking, and sleeping, second. The body’s twenty-four-hour clock, also known as our Circadian Rhythm, keeps the entire system in check and directs every aspect of our life.
The most well-known function of the twenty-four-hour tempo is the ability to signal to our body when it is time to sleep and wake. But this inner rhythm also regulates our appetite, emotions and moods, body temperature, metabolic rate, and release of hormones. Even the pattern of births and deaths are linked to the circadian rhythm due to the regulation of these critical life-dependent processes.
Even if all outside elements are taken away, sunlight included, the body will still regulate itself based around this twenty-four-hour cycle. Two sleep researchers underwent an intense scientific study when they chose to separate themselves from the outside world and track how their bodies responded.
Known as the Mammoth Cave experiment, Kleitman and his assistant uncovered a deeper understanding of our inner clocks and their ability to regulate the body. The month spent in a dark cave illuminated a new understanding of this innate rhythm.
However, the rising and setting of the sun is not the only factor that can regulate the circadian rhythm. Any activity you reliably repeat in a consistent matter becomes a cue for the brain to base it’s cycle off of.
When we eat, workout, and socialize can all affect our circadian rhythm and sleep-wake cycle. Together these daily, recurring activities will work in the same way that sunlight does to reset the clock back to its twenty-four-hour period.
The biological clock that keeps track of this cycle is located in the middle of the brain, called the suprachiasmatic nucleus. For playing such a crucial role in regulating the entire system, the suprachiasmatic nucleus is relatively small, as it is composed of 20,000 brain cells. This number may seem significant, but the brain is made up of over 100 billion neurons.
This tiny mind clock is what regulates the circadian rhythm, activating and deactivating both brain and body mechanisms based on this twenty-four-hour span.
This becomes apparent when we consider whether or not we’re morning people. Almost everyone can pinpoint the time of day when they feel most awake, inspired, or productive. For some individuals, that’s early in the morning, for others the afternoon, or the evening. In this regard, we are all marching to the beat of our own twenty-four-hour drum.