Advanced Sleep Phase Syndrome vs. Delayed Sleep Phase Syndrome

Dr. Colleen Ehrnstrom's profile picture
Dr. Colleen Ehrnstrom, PhD
May 8, 20226 min read

Advanced sleep phase syndrome (ASPS) and delayed sleep phase syndrome (DSPS) are conditions that cause your sleep schedule to be out of line with what is considered “normal” by society’s standards. ASPS and DSPS don’t necessarily affect how long you sleep — they affect when you sleep.1

If you have an unusual sleep schedule due to working a job or going to school outside of typical daytime hours, it doesn’t necessarily mean you have ASPS or DSPS. When people do have these conditions, they often want to follow a different sleep schedule, but their bodies don’t seem to let them.

If you feel like you may have signs of ASPS or DSPS, talk to your doctor. Treatment can help you safely and effectively adjust your sleeping patterns or cope with keeping an unusual schedule.

What Is Advanced Sleep Phase Syndrome?

ASPS, also called advanced sleep-wake phase disorder, causes you to be an extreme early bird. If you have this condition, for example, you may find yourself becoming very sleepy in the late afternoon and needing to get to bed in the early evening, despite wanting to stay awake longer. You may then find yourself naturally waking up extremely early in the morning, lying awake until your alarm eventually goes off.1

You may have ASPS if you:1

  • Get tired and fall asleep earlier in the day than you want to
  • Wake up early in the morning and can’t get back to sleep
  • Experience these symptoms nearly every day, including days when you have work or school as well as your free days
  • Have had these symptoms for at least three months

ASPS typically occurs due to predispositions or development changes in your circadian rhythm (internal body clock) and sleep drive (the process in your body that makes you feel increasingly sleepy the longer you are awake).1 These changes may develop because of genetics — about 40-50% of people with ASPS have a family member with the condition. Additionally, ASPS is more common among older adults.2

What Is Delayed Sleep Phase Syndrome?

On the other end of the spectrum, DSPS turns you into a night owl. If you have DSPS, you may find yourself regularly staying awake until the early hours of the next morning. In the absence of any responsibilities the next day, you might find yourself sleeping in until noon or later. Some experts also refer to DSPS as delayed sleep-wake phase disorder.1

You may want to talk to your doctor about DSPS if you:1

  • Don’t start feeling sleepy or aren’t able to fall asleep until very late
  • Struggle to wake up in the morning at a certain time
  • Experience these late sleep-wake times regardless of whether or not you are trying to follow a certain schedule
  • Have had these symptoms for three months or more

Like ASPS, DSPS can develop due to the underlying biology of  your circadian rhythm and sleep drive.1 DSPS is also more common in young adults and teens; about 7-16% of people within these age ranges have the condition. Additionally, many people with mental health disorders also have DSPS.3

Delayed Sleep Phase Syndrome and ADHD

Attention-deficit hyperactivity disorder (ADHD) is strongly linked to DSPS in some studies. ADHD is a condition that causes you to be inattentive (have trouble focusing or staying organized), hyperactive (moving around a lot when it is not appropriate), and/or impulsive (acting or speaking quickly without thinking it through).4

As many as three out of four people with ADHD may have DSPS.5 Studies have found changes in the genes that control circadian rhythms in people with ADHD. This causes certain body processes, such as hormone production, to occur 1.5 hours later than they would in people without ADHD.5,6

DSPS is also more common in people with psychiatric conditions like bipolar disorder, obsessive-compulsive disorder, depression, and substance use disorder.1

Treatment for ASPS and DSPS

Changing your sleeping patterns can be difficult on your own, but certain strategies can help. Although ASPS and DSPS look a little different, their recommended treatments are very similar.

Maintaining healthy sleep hygiene can be a good place to start. Sleep hygiene consists of habits that can help you develop higher-quality, more consistent sleep. You will want to try:7

  • Waking up at the same time each day
  • Staying away from coffee in the afternoon and evening
  • Avoiding naps, especially later in the day
  • Drinking less alcohol before bed
  • Using your bed only for sleeping
  • Staying out of your bedroom except when you want to sleep
  • Removing distractions involving bright lights or noise from your bedroom
  • Getting out of bed and doing something else for a bit if you can’t fall asleep

You can also try adjusting your lifestyle to match your natural sleep rhythm rather than fighting it. For example, if you have ASPS, you could try working or taking classes a little earlier in the day or meeting up with friends for happy hour rather than for a late dinner. If you have DSPS, you could try switching to an evening or night shift or making plans with loved ones later in the evening.

Bright light therapy or phototherapy is also an effective technique for treating ASPS and DSPS. This method involves using bright lights to shift your sleep-wake times and reset your circadian rhythms. If you have ASPS, this may involve surrounding yourself with light in the late afternoon or evening hours, while DSPS is treated with light exposure in the morning.1

Can CBT-I Treat ASPS or DSPS?

Although Cognitive Behavioral Therapy for Insomnia (CBT-I) was originally developed as an insomnia treatment, it is also an effective and well-known therapy for both ASPS and DSPS. CBT-I helps you learn more about your personal sleep habits and change your thoughts, attitudes, and behaviors surrounding rest.1

People with ASPS and DSPS often struggle with the pressure surrounding what society considers to be “normal” sleep and awake hours. CBT-I helps treat both of these syndromes because it targets how we feel about our sleeping patterns. To learn more about CBT-I, read Dawn’s in-depth guide.

If you are struggling to improve your sleep, try Dawn Health. We provide tailored CBT-I advice about sleep habits thanks to in-depth work with a one-on-one sleep coach. To learn more, fill out our questionnaire.


  1. Culnan, E., McCullough, L. M., & Wyatt, J. K. (2019). Circadian Rhythm Sleep-Wake Phase Disorders. Neurologic clinics, 37(3), 527–543.

  2. Stanford Health Care. What Is Advanced Sleep Phase Syndrome?

  3. Stanford Health Care. What Is Delayed Sleep Phase Syndrome?

  4. National Institute of Mental Health. (2021, September). Attention-Deficit/Hyperactivity Disorder.

  5. Lunsford-Avery, J. R., & Kollins, S. H. (2018). Editorial Perspective: Delayed circadian rhythm phase: a cause of late-onset attention-deficit/hyperactivity disorder among adolescents?. Journal of child psychology and psychiatry, and allied disciplines, 59(12), 1248–1251.

  6. Wajszilber, D., Santiseban, J. A., & Gruber, R. (2018). Sleep disorders in patients with ADHD: impact and management challenges. Nature and science of sleep, 10, 453–480.

  7. MedlinePlus. (2022, February 10). Healthy Sleep.

Dr. Colleen Ehrnstrom's profile picture
Dr. Colleen Ehrnstrom, PhD

Dr. Colleen Ehrnstrom is a licensed clinical psychologist with a specialty practice in Acceptance and Commitment Therapy (ACT). Areas of expertise include insomnia and other sleep disorders, anxiety, and depression.

Dr. Ehrnstrom is not a medical provider and is not providing any recommendations regarding medications. Rather, she is sharing and reviewing the research as it relates to education when learning how best to treat insomnia.

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