Delayed Sleep Phase Syndrome in ADHD: Causes, Signs, and Treatment

We’ve all been there: lying in bed wide awake in the early hours of the morning, unable to fall asleep (or back asleep) while experiencing mounting anxiety about how difficult this will make the next day. When this happens, it’s rarely due to bad habits or poor discipline. This concern can be the result of a circadian rhythm disorder called Delayed Sleep Phase Syndrome, which many people with ADHD experience.

In this article, we will discuss how DSPS impacts the body and mind, the ways it intersects with ADHD, and how you can manage this condition. We will also outline how Sound for Sleep by SoundSory is an evidence-based option to help ease the effects of DSPS in children and adults.

What Is Delayed Sleep Phase Syndrome (DSPS)?

Delayed Sleep Phase Syndrome (also known as Delayed Sleep-Wake Phase Disorder, or DSWPD) is a disorder that impacts the body’s natural clock, which is called our circadian rhythm. Individuals with DSPS have an internal clock that is delayed by 2 or more hours. This means they go to bed later than most people do and wake up later than most people do. 

As you can imagine, this condition often has an impact on someone’s ability to consistently be on time for and participate in school, work, and even social activities. Mood changes, behavior difficulties, and extreme daytime sleepiness associated with DSPS all have an impact on someone’s functioning during the daytime.

How the Circadian Rhythm Controls Your Sleep-Wake Cycle

In order to function properly, our body needs to maintain a balance in all of its processes (called homeostasis). The act of falling asleep and waking up are two of these processes guided by circadian rhythms. A person’s circadian rhythm, also known as their ‘body clock,’ runs on a 24-hour schedule and sends signals to the brain that make them sleepy and drowsy (in preparation for rest) or alert and awake (to get them ready for activities). Circadian rhythms are responsive to environmental light, as this biological function has evolved over time to help a person’s circadian rhythm synchronize with their surroundings. 

While there are several hormones and other natural chemicals in the brain involved in aligning circadian rhythms, the main organ that keeps time is called the suprachiasmatic nucleus. However, recent research has shown a strong connection between the suprachiasmatic nucleus and other organ systems, which were found to contain sensors of a sort that relay information to the nucleus located in the brain. These include the spleen, kidneys, intestines, heart, liver, lungs, skin, intestines, prostate, adrenal gland, smell-related parts of the brain, esophagus, and white blood cells. As you can imagine, this makes sleep especially vital to the function of many parts of our body.

The Role of Melatonin in Sleep Onset

Sensing light and darkness impacts our sleep by triggering the production of melatonin. Melatonin is a natural hormone released from a part of the brain called the pineal gland. Melatonin helps us feel physically tired, which allows us to begin preparing for sleep. Individuals with DSPS tend to have delayed release of melatonin, which is part of what makes them awake at night when other people typically tend to feel tired. Typically, melatonin is produced in the early evening through the remainder of the night (often between 7 and 11 pm), but individuals with DSPS may not begin producing melatonin until the end of this time range. This also causes them to continue producing melatonin beyond when people usually do in the early morning, which makes their fatigue and sleep extend beyond that range as well.

DSPS Is Not the Same as Being a Night Owl

It may seem as if DSPS-related concerns stem from people making a choice to stay up later. However, people with this condition are not what are traditionally viewed as night owls. Night owls are people who choose to stay up late for whatever reason, be it the solitude, quiet, or ability to unwind better during those nighttime hours. Night owls may also be early risers and prefer the early morning hours for much the same reasons.

However, people with DSPS have consistent difficulty falling asleep even when they adjust their environment or make attempts to get to bed earlier. This is what differentiates DSPS from other sleep disorders and traditional insomnia.

The Link Between Delayed Sleep Phase Syndrome and ADHD

Research estimates that around 75% of adults who were affected by ADHD during their childhood go on to have phase-delayed circadian rhythms. This is an incredibly high rate, but it’s understandable when you consider the biological changes that both conditions cause a person to experience.

In particular, symptoms of ADHD and sleep disturbances in general both cause changes to several parts of the brain, including the frontostriatal circuitry and the ventral attention system. The ventral attention system operates much like radar in that it directs the brain’s attention to unpredictable events or stimuli from our surroundings. Frontostriatal circuitry contributes to someone’s ability to make decisions and be flexible in the face of change and other daily events. Anyone living with ADHD and experiencing sleep concerns may recognize that they have problems in these areas when they are especially symptomatic or overtired.

Why DSPS Is So Common in People With ADHD

As we mentioned above, many of the brain structures that control cognitive functions such as attention also impact our behavior and the timing of our sleep and wake cycles. The prefrontal cortex, which controls many higher-level functions such as decision-making, level of arousal, attention, organization, and planning, helps shift our attention in various directions. This part of the brain may be overactive during the evening, shifting someone’s energy up when their nervous system should be winding down.

Additionally, the thalamus is a part of the brain considered a relay station since it’s charged with taking in and processing information from our environment. The functions of the thalamus closely intersect with attention, and this part of the brain also helps regulate sleep-wake cycles. As you can see, there is a high degree of crossover between the internal mechanisms of ADHD and DSPS.

How Dopamine Dysregulation Delays the Body Clock

We’ve talked about melatonin and its role in sleep, but other natural chemicals called neurotransmitters also stand to impact our sleep. Dopamine is one such example. During the day, dopamine suppresses melatonin production, which keeps us awake, alert, and active. At night, however, melatonin suppresses dopamine production. This is what signals our brain and body that it’s time for sleep.

This differs in people with ADHD, though. The biological mechanisms of ADHD cause an imbalance between the dopamine and melatonin synergy. Therefore, people may have higher levels of melatonin during the day (leading to daytime sleepiness) and higher levels of dopamine at night (causing greater alertness starting in the evening and extending into the night).

The Genetic Connection Between ADHD and Circadian Rhythm Disruption

When looking more closely at the biology behind ADHD and circadian rhythm disorders such as DSPS, there are several genetic changes that also may play a part. CLOCK gene polymorphisms (specifically T3111C) and PER2 variants have both been linked to the development of both ADHD and DSPS. Additionally, these genetic variations can also contribute to psychiatric conditions such as schizophrenia and depression, which are also known to cause sleep disturbances.

How Stimulant Medications Can Shift Sleep Timing Further

Biological changes aren’t the only reason sleep disorders are more likely to occur in individuals with ADHD compared to the general population. Individuals with ADHD who take stimulant medications may experience even more delays in sleep and wake cycles. For instance, methylphenidate (more commonly known as Ritalin) can further shift wake times and delay sleep times. This makes it especially important to properly time when these medications are taken. It may be most appropriate to start with lower doses and take them as early in the morning as possible to maximize their effect on daytime function while minimizing their disruption to sleep.

Symptoms of Delayed Sleep Phase Syndrome in People With ADHD

Some DSPS symptoms may overlap with people who have ADHD. However, there are clear signs that someone is living with DSPS, as they will demonstrate the following symptoms:

• Excessive daytime sleepiness
• Significant difficulty waking up each morning
• Difficulty falling asleep at the same time as peers
• Feelings of energy and alertness in the evening

Difficulty Falling Asleep at a Conventional Bedtime

People with ADHD may experience racing thoughts that get in the way of their ability to fall asleep. However, DSPS difficulty falling asleep goes beyond that. The brain and body in people with this condition are both in a state of heightened activity, making them simply not ready for sleep as they should be in the evening.

Extreme Difficulty Waking Up in the Morning

People with DSPS may need to set multiple alarms or sometimes even rely on other people to get them up in the morning. This is because their brain is in a deeper state of sleep than most people are in the morning hours. Their later bedtime causes these sleep phases to all be delayed, making them often unprepared to wake up at the time they need to. This DSPS symptom impacts attention, sensory regulation, and other concerns many people with ADHD live with.

Daytime Sleepiness and Fatigue

These changes in sleep phases lead people with DSPS to deal with excessive fatigue during the day. This leads to ADHD symptoms such as hyperactivity, poor working memory, and inattention being worse than they would otherwise be.

Feeling Alert and Energized Only in the Evening

People with this condition have likely become accustomed to their peak energy levels, which often are later in the evening and sometimes even further into the night. Children, especially those with growing amounts of homework and studying to do, may get in the habit of doing their work during these hours. The same may also apply to adults with cleaning, paying bills, and other household obligations. Feelings of productivity after these sessions only tend to reinforce their delayed sleep cycles and routines. They may even begin working on important tasks later in the day as a result of knowing how their energy levels are.

How Is Delayed Sleep Phase Syndrome Diagnosed?

Since DSPS treatment is condition-specific, it is important for individuals to get properly diagnosed so their treatment plan is accurate to their needs. There are several ways to diagnose Delayed Sleep Phase Syndrome, most of which involve medical tests. You can mention this concern to your doctor, who will likely refer you to a sleep specialist to begin the diagnostic process.

Sleep Diaries and Actigraphy

Actigraphy and sleep diaries are both some of the most evidence-based ways to diagnose DSPS. Sleep diaries involve tracking when you go to sleep and wake up for a period of at least 7 days. This allows providers to get an idea of each person’s total sleep time and how this compares to the time they turned the lights out at night and on in the morning. Actigraphy is a wearable device (often on the wrist) that tracks objective data for your provider to analyze. Since it primarily tracks your movement, it is another way of determining exactly when you fell asleep each night and woke up each morning. These are typically used in combination to ensure as much accuracy in reporting figures as possible.

Dim-Light Melatonin Onset (DLMO) Testing

Since DSPS significantly affects a person’s melatonin production, testing those levels in the body is another important part of the diagnostic process. DLMO is considered the gold standard way of medically testing a person’s circadian rhythm. While it’s possible for a primary care doctor or other standard physician to ask for sleep diaries and actigraphy, DLMO is most often administered by a sleep specialist.

Ruling Out Other Sleep Disorders

Any medical evaluation must be comprehensive, which is why providers will also ask questions and perform tests to rule out similar health conditions. In the case of DSPS, this includes other sleep disorders such as the two forms of sleep apnea, restless leg syndrome (RLS), and insomnia. A polysomnography is one example of a test that can help differentiate between sleep disorders. 

Polysomnographies are sleep studies that track a person’s brain waves along with standard vital signs, including heart rate, breathing rate, and blood oxygen levels, as a person sleeps. These are typically done in outpatient clinics or special wings of hospitals. It is important for a person to sleep as close to how they typically would so the provider can see what is reflected in the data.

How Delayed Sleep Phase Syndrome Makes ADHD Symptoms Worse

As with many health conditions, Delayed Sleep Phase Syndrome can make symptoms worse in people who have ADHD. In turn, ADHD habits (such as difficulty starting tasks, sensory processing impairments, and mental disorganization can all make sleep more difficult for people who also have DSPS. We will explain the relationship between various skill areas in DSPS and ADHD.

Executive Function and Attention

Executive functions are higher-level cognitive functions such as scheduling, planning, prioritizing, judging, decision-making, attention, memory, and organization. When a person is sleep deprived, they tend to have a shorter attention span, more limited working memory, less cognitive flexibility, and poorer inhibition (also known as self-control). These are all areas that already tend to be impaired as a result of ADHD, and sleep deprivation can cause them to further worsen.

Emotional Dysregulation and Mood

A study from the American Academy of Sleep Medicine found that 74% of Americans often, sometimes, or always have sleep disruptions stemming from anxiety or stress. When someone chronically gets poor sleep, they are at a heightened risk of mood and personality changes, including irritability, higher levels of emotional reactivity, and a greater risk of depression.

Academic and Workplace Performance

Since kids’ school schedules and most adults’ work schedules take place during the daytime, people with DSPS tend to persistently have misaligned daytime and sleep schedules. This can lead to performance issues, including tardy arrivals, absenteeism, brain fog, and difficulty fulfilling work responsibilities.

Long-Term Physical Health Risks

It is well known how many physical health risks are associated with sleep deprivation. Research has linked long-term sleep deprivation with a greater risk of metabolic conditions (including but not limited to diabetes), lower immunity levels (placing people at higher risk of all sorts of communicable illnesses), heart disease, hypertension, and obesity, among others.

Self-Medication With Caffeine, Alcohol, and Cannabis

If individuals living with DSPS do not receive the proper treatment, they are likely to find their own ways to cope with the condition. In many cases, this leads to self-medication using substances such as caffeine to manage daytime sleepiness and cannabis or alcohol to help them sleep at night.

DSPS vs. Bedtime Procrastination in ADHD – How to Tell the Difference

Bedtime procrastination is common in people who have ADHD, but it shouldn’t be confused for a distinct sleep disorder. When people with ADHD put off going to bed, this is a voluntary choice they make. It stems from an effort to get more dopamine to put their mind at ease. This may possibly be an effort to relieve racing thoughts or calm anxiety in other forms. DSPS is not a voluntary choice; rather, it is a condition that causes delays in sleep phases.

	DSPS	ADHD
Voluntary sleep delays	No	Yes
Sleepiness at a socially acceptable bedtime	No	Maybe
Can be helped by removing stimuli	No	Yes
Circadian rhythm disruptions	Yes	Yes
Increased mental or physical energy in the evening hours	Yes	Yes
Difficulty staying asleep	No	Maybe
Responds well to behavior-related sleep strategies	No	Yes

DSPS vs. Insomnia – Why They Are Often Confused

DSPS is not a very well-known condition, making it easy to be mistaken for insomnia or other sleep disorders. The distinction between the two, though, is important since this leads to effective treatment.

	DSPS	Insomnia
Sleep onset difficulties	No	Yes
Circadian rhythm disruptions	Yes	Yes
Increased mental or physical energy in the evening hours	Yes	Maybe
Good sleep quality once asleep	Yes	No
Responds well to behavior-related sleep strategies	No	Yes
Responds well to sleeping pills	No	Yes

Biological Markers of Circadian Disruption in ADHD

There are measurable differences in the circadian systems of people with ADHD. These biological changes lead people with ADHD to have disruptions in circadian rhythms, which impact sleep and other bodily processes.

Delayed Melatonin Onset in Children and Adults With ADHD

Melatonin is released in the evening to prepare the body and mind for bedtime. This response occurs as a result of dim lights (which is why removing electronic devices and other sources of artificial light is so important). However, children with ADHD are known to release melatonin around 45 minutes later than children without this condition. A similar trend can be seen in adults, with up to a 90-minute delay in melatonin release compared to peers.

Blunted and Delayed Cortisol Rhythms

In the morning, hormones such as cortisol rise, which helps give us the boost and sense of urgency needed to get our day started. However, adults with ADHD have a delay in the release of this natural substance. In addition, when it does rise, it doesn’t rise as high as it does in people without ADHD.

Clock Gene Expression Differences (BMAL1 and PER2)

Genetic changes also play a part. Individuals with ADHD have attenuated rhythmic expression of the BMAL1 and PER2 genes. BMAL1 helps the body maintain homeostasis, which is the balance between all of its bodily processes. PER2 helps sensory regulation as well as the regulation of circadian rhythms. When these two genes are mutated (as they often are in ADHD), people with the condition and sleep disorders tend to have more symptoms of circadian rhythm disruptions.

Reduced Pineal Gland Volume

ADHD causes individuals to have smaller pineal glands. If you remember, we discussed earlier how the pineal gland helps produce melatonin as well as some other hormones. It also helps sense when the environment is light or dark, which serves as a trigger for the release of melatonin.

DSPS and ADHD in Children vs. Adults – Key Differences

DSPS presents differently depending on a person’s age. For instance, children with DSPS may be seen as difficult or hyperactive for not going to sleep when they should. Adults may be branded as night owls for choosing to get things done in the evening when they have more energy. Timely diagnosis is another way to get connected with treatment as soon as possible.

How Adolescence Triggers Circadian Phase Delay

Once a child reaches puberty, their body’s circadian rhythms naturally shift. Before puberty (around 9 or 10 years old), it is common for the body’s rhythms to cause sleepiness around 8 or 9 pm. After puberty, this sleepiness doesn’t start until 10 or 11 pm. Since each child starts puberty at a different time (girls usually do before boys), this can take parents by surprise. However, the shift tends to be even more dramatic in children and teens who have ADHD due to their biological makeup.

Why DSPS Often Persists Into Adulthood in People With ADHD

Another shift in circadian rhythm preference typically occurs in early adulthood. In the general population, sleep tendencies shift back to a preference for mornings, which aligns well with the college and/or early career years for most people. Yet, circadian rhythm preferences still tend to remain chronic later in adults who have ADHD.

The Misdiagnosis Problem in Children and Adolescents

DSPS symptoms in young people are usually attributed solely to ADHD, as this is one of the more common conditions, especially with the notoriety it has gotten in recent years. DSPS symptoms may also be mistaken for depression, behavioral problems, sensory concerns, or insomnia. Therefore, misdiagnosis can cause even greater confusion about whether shifts are typical or not.

Treatments for Delayed Sleep Phase Syndrome in ADHD

To be effective, DSPS treatments must directly target the circadian clock. It is important to note that DSPS is a distinct condition from insomnia; therefore, standard insomnia techniques are considered largely ineffective for DSPS. We will cover some DSPS treatments below.

Light Therapy – Resetting the Circadian Clock With Morning Light

Bright light exposure is essential within 2 hours of waking, as this helps the body naturally reset its circadian rhythm. Morning light helps the body and brain recognize its surroundings and gradually adjust its processes to reflect that. People should also avoid light before their core body temperature gets to its lowest point, which traditionally happens around 6 hours after falling asleep. This means going to sleep in a room where the temperature is relatively constant. Lastly, dimming all lights, screens, devices, and other sources of light in the evening will help the body recognize its nighttime.

Melatonin Supplementation – Timing, Dosage, and What the Research Shows

When taken around 6 hours before the time they would naturally fall asleep, low doses of melatonin (~1-3 milligrams) can be helpful. While there are several doses available, the timing of the melatonin is far more important to shifting the body’s natural tendencies than the dose a person takes.

Chronotherapy – Gradually Shifting Sleep and Wake Times

Chronotherapy is a behavioral strategy that involves consistency in slowly, gradually shifting one’s bedtime to achieve more natural sleep and wake times. This involves going to bed 15 minutes earlier and waking up 15 minutes earlier, allowing your body to adjust to this for 1-2 weeks, then shifting another 15 minutes earlier. This will continue until someone achieves a more acceptable sleep and wake schedule. As with most treatments, this requires strict consistency in order to be effective.

Sleep Hygiene Adjustments for the ADHD Brain

• Making the sleep environment as comfortable and calming as possible
• Using relaxation techniques before bed
• Creating a consistent, predictable routine in the evenings leading up to bed
• Getting exercise during the day
• Planning naps thoughtfully during the day so they don’t impact sleep
• Limiting caffeine and sugar intake
• Avoiding screens 2 hours before bedtime

Behavioral Sleep Interventions and CBT-I

Cognitive Behavioral Therapy for Insomnia (CBT-I) can be helpful for individuals who have sleep problems. While DSPS is distinct from insomnia, CBT is generally beneficial for a range of health conditions. CBT-I uses cognitive strategies to reframe negative thought patterns and beliefs that may impact the development of healthy habits, chiefly sleep. Research shows this better helps manage sleep challenges and emotion regulation in people with ADHD.

Optimizing ADHD Medication Timing to Protect Sleep

ADHD medications such as stimulants should be taken at a time and in a dosage that doesn’t affect sleep. This should be done with doctor supervision, but even on its own, this technique stands to improve delayed sleep onset in the majority of adults with both conditions.

Why Calming Audio Helps the ADHD Brain Wind Down

Since the brain of someone with ADHD tends to struggle with transitions, it can be difficult to shift from alert to relaxed and vice versa. This makes relaxing before bedtime especially trying. When used to assist with sleep, structured calming audio provides predictable sensory input that supports this shift without screens or the need to make decisions. Sound for Sleep by SoundSory is a bone conduction pillow speaker with a structured 8-night music program using classical, Celtic, and lullaby tracks that gradually slow down to encourage sleep.

Sound for Sleep by Soundsory – Built for ADHD and Sensory Sensitivity

Sound for Sleep is an integrated therapeutic sleep program that is an excellent fit for people with sleep anxiety among other conditions.

• What it is: A bone conduction pillow speaker that slides under the pillow for easy listening. Bone conduction pillow speakers offer a quiet listening experience that is only heard by the user, as they send gentle vibrations through the bones of the head rather than through the environment and into the ears.
• What it has: A built-in 8-night structured music program that eliminates the need for a playlist or phone that you select songs on.
• Who it’s meant for: Children and adults with anxiety, sensory sensitivity, ADHD, autism, and sleep difficulties
• Key features: Sound for Sleep has an automatic shut-off, charges easily with any USB-C cord, and is Bluetooth compatible. This speaker also has an 8-hour battery life and is made with dual bone conduction transducers that give off high-quality sound.
• Why it’s good for DSPS: Medication-free, screen-free, private listening experience with gradual sound modulation.

You can learn more on the SoundSory website and online store, but keep in mind that Sound for Sleep is not a medical treatment. It is important to know when medical treatment is needed to manage DSPS.

When to See a Sleep Specialist

If you or someone you know is experiencing persistent sleep problems, it may be time to contact a professional for help. Some signs of this include:

• Continual fatigue and low energy during the day despite receiving ADHD treatment
• Impaired performance in school, work, or social activities
• Worsening ADHD symptoms despite receiving ADHD treatment
• Major mood changes such as depression, irritability, and anger
• Persistent sleep difficulties despite sleep hygiene and other changes

If these signs pop up, it’s best to speak with a sleep specialist, psychologist, or primary care doctor (who can send you to the appropriate professional). Any of these professionals can walk with you in the right direction to help you better manage DSPS alongside ADHD.

Wrapping Up

Delayed Sleep Phase Syndrome is a distinct, treatable circadian rhythm disorder. People should recognize that DSPS is not the result of laziness, poor habits, or standard sleep difficulties such as insomnia. Parents should not scold their children about their sleep, and adults should not feel less than as a result of their sleep difficulties. This is only likely to cause additional stress and anxiety surrounding sleep problems and can even lead to self-esteem concerns.

It is important to accurately identify DSPS to take the steps necessary to manage it. With a combination of light therapy, behavioral strategies, melatonin, and a structured calming audio program, individuals with DSPS can improve both their sleep and ADHD symptoms along with their quality of life.

FAQs About Delayed Sleep Phase Syndrome and ADHD

What is delayed sleep phase syndrome? 

DSPS is a circadian rhythm disorder that makes a person’s sleep and wake time later than usual. DSPS is also known as delayed sleep-wake phase syndrome.

Is delayed sleep phase syndrome common in people with ADHD?

Yes. Around 75% of people with ADHD also have DSPS or other sleep disorders due to shared biological changes in the brain.

Why does my child with ADHD fight bedtime every night?

There are many reasons why children with ADHD may resist bedtime. It’s important to determine the reason to develop proper management strategies.

Can DSPS be cured, or is it lifelong?

There is no cure for DSPS. But, as with other chronic conditions, there are treatments and strategies that can help people manage the symptoms of DSPS.

How is DSPS different from insomnia? 

People with insomnia traditionally have difficulty getting to sleep, but fewer concerns waking up. DSPS causes someone to feel tired, go to sleep, and wake up 2 or more hours later than people without the condition.

Does Sound for Sleep by Soundsory replace medication for DSPS? 

Sound for Sleep is an example of a natural approach to managing DSPS. For some people, it may be able to replace medication, but it can also be used alongside medication for those who choose to do so.

Is Sound for Sleep safe for children with ADHD or autism? 

Yes! In fact, Sound for Sleep was specially designed for children with ADHD, Autism, Sensory Processing Disorder, and other neurodevelopmental conditions.

Will a bone conduction pillow speaker disturb my partner? 

No. Bone conduction speakers are designed intentionally so that people can use them without disturbing partners or others sleeping nearby.

Can fixing DSPS improve ADHD symptoms?

Yes. Sleep deprivation can worsen ADHD symptoms, so addressing sleep challenges can help someone with ADHD more effectively manage their symptoms.

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