Interesting Sleep Research on Circadian Rhythms
In one lot of research, volunteers were placed in special apartments or caves for several weeks, with no clocks or other time cues. Interestingly, without time cues, these volunteers went to bed roughly an hour later and awoke roughly an hour later each day. The results of these experiments appeared to show that humans have a free-running circadian rhythm of approximately 25 hours.
However, because these volunteers were able to control artificial lighting and the evening light caused a phase delay, more research was carried out. This new research showed that all adults free-run at an average of just over 24 hours (24 hours and 11 minutes, to be precise!). Our biological clock requires regular environmental time-cues in order to maintain a 24-hour day/night cycle. These time-cues, also known as zeitgebers, include our daily routine, and sunset and sunrise. We need time-cues to keep our normal human circadian clock aligned with the rest of the world.
There’s a continuum of chronic types among people with healthy circadian clocks, ranging from ‘morning’ people (larks) who prefer to go to sleep early and awaken early, to ‘evening’ or ‘night’ people (owls), who prefer to go to sleep late at night and awaken late in the morning. Regardless of whether people are larks or owls, those with normal circadian systems can –
- Wake up and go to sleep at the same time every day, if they choose to;
- Fall asleep at night allowing enough sleep time before having to get up, and can awaken in time for whatever they need to do in the morning;
- Start to fall asleep earlier each night and get up earlier than usual within just a few days, if a new routine so requires. Adapting to an earlier sleep/wake time is known as ‘advancing the sleep phase’, and it’s very possible for healthy people to advance their sleep phase by approximately one hour each day.
Are there risk factors for developing a circadian rhythm disorder? Although anyone can develop a circadian rhythm disorder including children and teens, certain factors increase the risk. For instance, people who frequently travel across time zones and those who work the night shift are at an increased risk.
How are circadian rhythm disorders diagnosed? If you suspect you have a circadian rhythm disorder, you should consider seeing a sleep specialist. You may be asked to keep a sleep diary, and a sleep study may also be recommended.
Do I need treatment if I have a circadian rhythm disorder? Since circadian rhythm disorders lead to a lack of quality sleep, treatment is beneficial. Treatments can improve regular sleep patterns and help you get the restorative sleep your body needs.
Is there a way to prevent circadian rhythm disorders? Although it’s not always easy, maintaining a consistent sleep schedule is one of the best ways to prevent a circadian rhythm disorder.