The natural cycle of physical, mental, and behavior alterations that the body goes through in a 24-hour cycle. Circadian rhythms are mostly affected by light and darkness and are controlled by a small area in the middle of the brain. They can affect sleep, body temperature, hormones, appetite, and other body functions.
Abnormal circadian rhythms may be associated to obesity, diabetes, depression, bipolar disorder, seasonal effective disorder, and sleep disorders such as insomnia. Circadian rhythm is sometimes called the “body’s clock.”
The circadian rhythm dips and rises during the different parts of the day. For most adults, the strongest sleep drive(dip in energy) happens in the middle of the night between 2:00 am to 4:00 am and in the afternoons between 1:00 pm and 3:00 pm post lunch. Post this lunch, we generally crave for a nap. We won’t feel the dips and rises of circadian rhythm when we have had a sound sufficient sleep. Our body clock also causes us to feel more alert at certain points of the day.
Hypothalamus (a small portion of your brain) controls our internal body clock. External factors i.e. lightness and darkness can also impact it. When it’s dark at night, our eyes indicate to the hypothalamus that it’s time to feel tired. Our brain, in turn, sends a signal to our body to release melatonin, which makes our body tired. This is the reason why our circadian rhythm tends to coincide with the day’s lightness and darkness of the day.
SLEEP PATTERNS OF ELDERLY
The sleep cycle is repeated several times during the night. With aging, sleep patterns tend to change. Most people find that aging causes them to have a harder time falling asleep. They awaken more often during the night and earlier in the morning.
Circadian disruptions such as jet lag puts us in conflict with our natural sleep patterns, since the shift in time and light signals the brain to alter its normal pattern to adjust. This is why jet lag can leave travelers feeling poorly. And having difficulty thinking and performing well.
Our circadian rhythm works the best when you have uniform sleep habits, like going to bed and waking up the same time from day to day (including weekends).