Are You a Night Owl or a Morning Lark?

Circadian Preferences Impact Insomnia and Sleepiness Tendency

A boy wakes out of bed like a morning lark. Getty Images

It may seem like a silly question, but it can have profound implications on your sleep: Are you a night owl or a morning lark? Learn how your preferred sleep timing, reflecting your circadian rhythm and a consequence of genetics and other factors, may impact your risk of insomnia and daytime sleepiness.

It can be helpful to reflect a little on your best ability to stay awake or your strongest desire for sleep.

When you think about your day, when do you feel most awake and productive? When do you get a “second wind” and find your mental clarity, concentration, and energy levels peak? Is it first thing in the morning or perhaps late in the evening? Conversely, when do you hit a wall and feel extra sleepy? Is there a time that you are most likely to want to take a nap? When do you fall asleep easiest and when do you wake feeling most refreshed? These considerations can help guide you to discover your preference: whether you are a night owl or a morning lark.

A night owl may be someone with a tendency toward delayed sleep phase syndrome (DSPS). Their best sleep occurs overnight between the hours of 1 to 2 AM and 9 to 10 AM. This optimal sleep period sometimes can shift even later. If an earlier bedtime is attempted, insomnia occurs as this is often when they feel very awake. If an early morning awakening is required, it can be very difficult to wake.

Multiple alarms may be required and sleep inertia may lead to tardiness, absenteeism, or poor concentration and sleepiness in the first part of the morning. DSPS often becomes evident in teenagers and may persist throughout life. It affects about 10% of people.

At the other extreme are the morning larks, those individuals who may have advanced sleep phase syndrome (ASPS) and feel sleepy very early and retire to bed before most do.

Early morning awakenings also result, often as early as 4 or 5 AM. These awakenings are not due to other causes, such as sleep apnea or depression, and will persist even with a late bedtime. ASPS affects less than 1% of people.

It is possible to have a preference – identifying as a night owl or morning lark – without having a sleep disorder. Less extreme tendencies commonly occur, and there may be a broad spectrum of variation that can even change throughout life or due to specific circumstances. It is definitely not a problem if there are no consequences and you are able to sleep and wake at your will.

If your preferred sleep timing leads to difficulty initiating or maintaining sleep, it may prompt treatment for insomnia. Teenagers in particular may struggle as they stay up late and can’t get to school on time. Melatonin may be weakly effective. Properly timed light exposure and a regular sleep schedule can be very helpful. In some cases, cognitive behavioral therapy for insomnia (CBTI) may be used.

If your preferred sleep pattern is negatively impacting your life, speak with a board-certified sleep specialist about your options and discover the sleep of your dreams.


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