You might probably think that the connection between our sleep and mood is quite obvious. We’ve all experienced a sense of drowsiness, annoyance, and fatigue after a long night studying, working, or partying. You’ve probably also heard about those eight hours of sleep we all need, even though it doesn’t work for everyone. But what happens to us when we sleep or don’t sleep enough? And why do we not only feel tired but also irritated or unmotivated after some sleepless nights?

We’re quite used to imagining sleeping as some kind of charging, like with a phone, for example. The similarity is quite striking on the surface. If we charge our phone only to 60-70%, it might not last through the day. However, if the device is not fully charged, it’s unlikely to slack on browsing pages or snap back at you after you try to click the same button over and over to make something load faster.

You’re probably thinking now: “Duuh, I’m not a device.” — True. We are, in fact, way more complex than a device or machine, yet we often lack understanding of how our “battery” works. We’re also often too hard on ourselves for not being able to perform, even though we’re not “charged” enough and are (really) not machines. 

Sleep and dopamine share a profound connection. They influence our mood, focus, and overall mental health. Dopamine, a neurotransmitter critical for motivation and reward, is also tied to the sleep-wake cycle, also known as the circadian rhythm. 

This rhythm regulates when we feel alert and when we feel tired, with dopamine playing a central role. Keep in mind that other neurotransmitters, including serotonin, adenosine, and melatonin, also play a role in sleep regulation, not just dopamine.

The human brain’s ability to maintain balanced dopamine levels significantly impacts our mood and ability to stay motivated. However, disturbances in sleep, whether from poor habits or external factors, can lead to shifts in dopamine levels and rest. This often results in mood disorders and cognitive challenges.

Emerging research highlights that sleep deprivation and dopamine are closely linked, with chronic sleep loss leading to disrupted neurotransmitter balance. That’s what we want to explore today: how quality sleep and mood are interconnected, practical strategies for improving sleep for mental health, and the long-term benefits of maintaining a healthy sleep schedule for motivation and emotional well-being. So, let’s dive in.

How Sleep Affects Dopamine Levels

Dopamine, often called the "motivation molecule," is vital in the sleep-wake cycle. Researchers conclude that its levels fluctuate throughout the day, peaking during active, wakeful periods and tapering off as we approach nighttime (Alonso et al., 2020). This daily rhythm helps ensure you stay energized during the day and relaxed enough to sleep at night.

One of the most important stages of sleep, Rapid Eye Movement or REM sleep, acts as a reset button for your brain's dopamine systems, as it is characterized by higher dopamine release. But what exactly is REM, and why is it important? Here are some things to know about:

• It is one of four sleep phases. Our sleep cycle includes N1 and N2 phases (also called light sleep), N3, or deep sleep, and, finally, REM, or a vivid dreaming phase. During normal sleep, we usually go through four or five cycles.
• During REM, our heart rate, blood pressure, brain activity, and breathing increase. Your eyes move rapidly despite being closed (hence the name, ‘Rapid Eye Movement’). At the same time, the muscles in your legs and arms are temporarily paralyzed.
• The first period of REM sleep typically happens after about an hour and a half into sleeping and continues for about ten minutes.

During this phase, emotional memories are consolidated, and neurotransmitter systems are rebalanced. But when your sleep is disrupted (for example, due to chronic insomnia or simply a late-night binge-watch), your dopamine balance can be affected negatively. This imbalance often results in mood swings, diminished focus, and reduced motivation.

A study by Alonso et al. (2020) further highlights how dopamine levels and sleep states are linked. Higher dopamine activity has been observed during wakefulness, while the neurotransmitter’s uptake rate increases after sleep. This ensures your brain starts the day with refreshed dopamine pathways. On the other hand, sleep deprivation has been shown to disrupt these natural cycles and affect the dopamine transporter’s ability to regulate levels effectively.

The Impact of Sleep Loss on Dopamine

If you don't sleep enough, your brain works overtime to compensate. To do that, it releases bursts of dopamine to keep you awake and alert. While this might seem helpful in the short term, it comes at a cost. Chronic sleep deprivation can exhaust your brain’s dopamine reserves, as it increases dopamine release in the striatum* (Lim et al., 2012).

*Striatum is a deeply seated brain structure located in the forebrain. It affects our motivation, reward, movement, and decision-making.

What Happens When You Lose Sleep?

1. A lack of sleep leads to irregularities in dopamine release and uptake, which can affect everything from mood to motor function (Oishi and Lazarus, 2017).
2. The pineal gland, which is a small endocrine gland that helps regulate your sleep-wake cycle by secreting melatonin, struggles to maintain balance, further throwing off dopamine’s natural rhythm (Alonso et al., 2020).
3. Dopamine, while promoting wakefulness, can also increase feelings of fatigue and irritability. Studies on fruit flies and humans alike show that dopamine’s role in sleep is more complex than simply keeping you awake, it can also promote sleep in certain brain regions (Fernandez-Chiappe et al., 2020).
4. Chronic lack of sleep can lead to various physical and mental health issues, including higher risks of mood disorders and memory impairment. Additionally, it poses significant risks for people with mental and neurodevelopmental disorders.

Tips for Improving Sleep Quality

Before going into how to improve our sleep quality, we need to acknowledge that every person is different, and not all of them will work for you. However, to find out what can really help, you need to understand the cause and try out different approaches. Let’s start with identifying the roots.

Lack of proper sleep doesn’t always fall under the category of sleep disorders. It’s often the consequence of our choices or a symptom of a more complex issue. It can also be caused by external factors outside of our control. Whatever the reason may be, without identifying it first, you can’t make significant progress. 

If sleep problems have been a major issue for you, please do not hesitate to reach out to your healthcare provider. They are qualified to look for a reason beyond guessing. This way, you can get much-needed help early enough to prevent the negative consequences.

Here are some common reasons behind sleep problems and how to recognize them:

Revenge Bedtime Procrastination

With our busy lifestyles, we often lose that precious “me time” due to work, studying, parenting, or everything combined. That leads many of us to feel the need to stay up late to reclaim that personal time, even when tired. 

However, that me time often consists of mindlessly scrolling on the phone or binge-watching a new Netflix series. Procrastination often correlates with high dopamine levels during evening activities (i.e., scrolling or watching series), which prevents the natural unwinding needed for falling asleep.

It is perfectly normal for us to feel the need to engage in these mindless activities. Not everything has to be productive or meaningful. But when the need to stay on our phone late starts taking away our real rest time — that’s when it becomes a problem. 

In that moment, you might feel like you’re unwinding and taking the time for yourself, even though you’re sacrificing your sleep. Unfortunately, when it becomes a habit, it may have long-term consequences. It could be compared to a payday loan. Yes, at the moment, you get something you feel like you really need, but remember — it usually comes with a high interest rate.

Difficulty Falling Asleep

It can be very frustrating when we go to bed early but just can’t fall asleep. The reasons may vary and range from simple things like a stressful day at work or an uncomfortable bed to complex issues like anxiety. 

You may experience:

• racing thoughts
• tension
• physical discomfort
• restlessness
• staying awake for more than 30 minutes

These may be the signs of more complex issues and require consulting with a doctor. If you experience these signs, do not simply brush them off. If left unattended, they may result in more serious issues.

Chaotic Schedules

Irregular sleep and wake times often cause circadian rhythm disturbances. It can be difficult to stick with consistent sleep and wake times, especially when working late or night shifts

If your sleep patterns are dictated by external factors rather than internal cues, you might have to consider some serious lifestyle changes to get proper rest. In this case, it will greatly depend on the circumstances. If you are a late-night worker, a new parent, or a student who combines studies and work, you might not be able to simply change your schedule. In that case, you will have to combine multiple sleep improvement strategies to be able to get more rest during the daytime, for example. We will discuss them a bit later.

Melatonin Deficiency

Another common issue that might be hard to spot — your melatonin levels went down. If you notice these signs, you might need to refer to a medical professional for support:

• Trouble falling asleep in a dark and quiet environment
• Feeling wide awake even when exhausted
• Daytime tiredness

Regular exposure to artificial light in the evening can suppress or stop melatonin production. As melatonin production can be stimulated by darkness, not using any screens before sleep and avoiding bright lights in the evening can help. More on how to create a comfortable sleep environment later.

Mental Health Challenges

Conditions like anxiety, depression, or ADHD often affect sleep. They can manifest both like difficulty falling asleep and persistent feelings of fatigue despite getting enough sleep. If you’ve been struggling with mental health issues and noticed sudden changes in your sleep patterns, you need to inform your doctor about it, as this may require the administration or change of medication. A professional will help you create strategies based on your current condition and monitor your state.

Now, let’s proceed to strategies you can implement to improve your sleep quality. They can be helpful regardless if you have issues or just want to get better rest.

Create a Comfortable Sleeping Environment

Enhancing sleep quality starts with cultivating a bedroom environment that supports rest. Light, temperature, and noise are critical factors. 

• Blackout curtains can block disruptive light;
• Cooler room temperature helps the body achieve the slight drop in core temperature needed for sleep. The best room temperature for sleep is between 61 and 68°F (about 16-20°C). Body temperature alterations are natural during sleep, but you can help your body get into sleep mode by adjusting external conditions;
• Minimizing noise promotes uninterrupted rest. 

With these changes, you can get deeper, more restorative sleep, particularly REM sleep, where dopamine pathways recalibrate.

Now, let’s talk about exposure to blue light from screens. This light suppresses melatonin production, which, in turn, delays the onset of sleep. Reducing screen time at least an hour before bed or using blue light-blocking glasses can help mitigate this effect. 

Instead of scrolling on your phone, consider activities that prepare your brain for rest, such as reading a book or practicing mindfulness exercises.

Stick to a Regular Sleep Schedule

Going to bed and waking up at the same time every day helps regulate your circadian rhythm. Over time, this consistency supports dopamine’s natural rise and fall, which will allow you to wake up refreshed and ready to tackle the day.

However, if there’s no way for you to stick to a schedule (for example, you are a parent of a newborn baby), take every opportunity to take a nap whenever possible. If you have a partner or a family member who can help you out, do not hesitate to ask them for help. If possible, try to schedule a time when you take a nap during the day while someone watches the baby and makes sure nobody disturbs you. There’s nothing shameful about it!

Avoid Stimulants Before Bed

Caffeine, nicotine, and even heavy meals can interfere with sleep. Instead, opt for calming evening activities, such as reading, meditating, or light stretching. Drink a glass of warm water or milk before bed if you’re feeling hungry. A light meal or snack can be a good option, too.

Building Sustainable Sleep Habits

Making sleep a priority doesn’t mean overhauling your entire routine overnight. Start small:

• Replace late-night screen time with a relaxing activity, such as listening to music, journaling or even taking a warm bath
• Create a wind-down routine to signal to your brain that it’s time for rest.

Consistency is key. Studies show that well-regulated sleep improves not only mood and energy but also the brain’s ability to optimize dopamine function (Oishi and Lazarus, 2017).

For some, even the best sleep habits might not be enough. Disorders such as insomnia or sleep apnea can severely impact the brain’s ability to regulate dopamine and maintain overall health. Untreated sleep disorders can have lasting impacts on dopamine regulation and overall health. 

The Benefits of Sleep for Mood and Motivation

We all know that sleep is important, but have you ever stopped to think about how it actually shapes your mood and motivation? Getting quality sleep isn’t about how well your brain and body recharge for the day ahead. Sleep impacts many of the brain’s processes, especially dopamine release, which influences your mood, focus, and drive. 

In short, better sleep means better motivation.

Let’s break down how sleep affects dopamine, and why you need it for a motivated, positive mindset.

How Sleep Affects Dopamine Levels and Mood

Short, fragmented sleep has a particularly serious impact on dopamine levels because it prevents the full progression of all stages of sleep. Dopamine neurotransmitter plays a huge role in how we feel and how motivated we are to do things (Kesner et al., 2022). It’s the chemical responsible for making you feel good when you achieve something or experience pleasure. But to keep dopamine working properly, you need quality sleep. It is arguably one of the best ways for your brain to maintain healthy dopamine levels and keep you emotionally balanced. Here's how:

• During sleep, your brain gets to reset its dopamine receptors, the cells that respond to dopamine.
• This process helps your brain get back into gear, which makes it easier to stay focused and motivated.
• If your sleep is disrupted or you’re not getting enough, it can throw off your dopamine system. This can, in turn, make it harder to feel motivated or positive.

Better quality sleep = better dopamine response

If you don’t sleep enough, your brain struggles to produce enough dopamine. As a result, you might feel unmotivated or mentally foggy the next day. What happens when sleep is interrupted?

Your body’s internal clock also relies on sleep to regulate dopamine. Disruptions to your sleep schedule can mess with this rhythm and impact your mood and focus. Short-term sleep disruptions cause emotional distress, cognitive and memory deficits, and increased stress-responsivity. In the long run, they may cause hypertension, cardiovascular disease, and metabolic syndrome, among other issues.

Short-Term Effects of Sleep Deprivation on Dopamine and Mood

When dopamine levels drop due to lack of sleep, our brain becomes less efficient at signaling the reward system. This means tasks that would normally feel rewarding may seem less engaging or even overwhelming. The resulting lack of motivation makes it harder to accomplish even simple tasks.

Sleep deprivation can make your brain work harder to keep you awake and alert by releasing bursts of dopamine, but this short-term fix can leave you feeling worse in the long run. 

Long-Term Effects of Sleep Loss

When sleep loss becomes chronic, it disrupts the brain’s natural processes and can lead to lasting consequences. 

Chronic sleep deprivation can reduce the sensitivity and number of dopamine receptors in the brain. This makes it harder to feel motivated or experience pleasure, which, with time, may lead to apathy or reduced drive.

This neurotransmitter is critical for the brain's reward system. Long-term sleep loss can make it difficult for you to experience satisfaction from activities that would typically feel rewarding, further decreasing motivation.

Persistent sleep issues are also closely linked to depression. They can impair your emotional regulation and make it harder to manage stress and negative emotions, which may increase the likelihood of developing depression.

It can also contribute to heightened anxiety, as the brain becomes less able to process emotions and manage stress effectively. People may experience more intense and frequent anxiety symptoms over time. These mental health issues are also typically followed by cognitive decline:

• Chronic sleep deprivation impairs memory consolidation, which means the brain struggles to store and retrieve information. These memory issues are more serious than when you enter the room and forget why you went there in the first place. It becomes harder to create and store new memories. For a student preparing for an important exam, this can be detrimental, as long hours of studying might not help get that desired grade and lead to frustration and feelings of failure.
• Difficulty concentrating, which can impact work, school, and daily life. The decline in cognitive functioning will eventually affect your performance. Struggling to have tasks done at work or seeing a decline in personal productivity can lead to anxiety. When this becomes a vicious cycle, getting back on track becomes even harder.
• It also affects areas of the brain responsible for planning and decision-making, leading to poor judgment and increased impulsivity over time.
• People who don’t get enough sleep may find themselves more easily overwhelmed by stress, as their brains are less able to manage the physiological and emotional impacts of stressors.

Long-Term Benefits of Quality Sleep for Mental Health

Getting quality sleep can have lasting effects on both your dopamine system and overall mental health. Here’s what happens long-term when you prioritize sleep:

• Over time, your brain will build stronger, more responsive dopamine receptors, making it easier to stay focused and motivated.
• Sleep helps balance dopamine and norepinephrine receptors, which support mood and emotional control.
• When you sleep well, you’ll notice a clear improvement in motivation, energy levels, and overall mood throughout the day.

Summary

Of course, our goal here is not to scare you into thinking that a few sleepless nights will ruin your mood and motivation forever. Learning about the importance of a good night's sleep and its benefits can help you introduce healthier habits, mitigate circadian rhythm disturbances, and, hopefully, take better care of your health.

The reasons behind sleep regulation issues vary. You may be struggling with melatonin synthesis, difficulty organizing your schedule, or even mental health issues. Whatever the case may be, remember that prioritizing your needs, changing your lifestyle, or seeking help is okay.

Quality sleep is key to your overall well-being. Please, take it seriously.

References

Alonso, I. P., Pino, J. A., Kortagere, S., Torres, G. E., & España, R. A. (2021). Dopamine transporter function fluctuates across sleep/wake state: potential impact for addiction. Neuropsychopharmacology, 46(4), 699-708.

Fernandez-Chiappe, F., Hermann-Luibl, C., Peteranderl, A., Reinhard, N., Senthilan, P. R., Hieke, M., ... & Helfrich-Förster, C. (2020). Dopamine signaling in wake-promoting clock neurons is not required for the normal regulation of sleep in Drosophila. Journal of Neuroscience, 40(50), 9617-9633.

Kesner, A. J., Calva, C. B., & Ikemoto, S. (2022). Seeking motivation and reward: Roles of dopamine, hippocampus, and supramammillo-septal pathway. Progress in neurobiology, 212, 102252.

Lim, M. M., Xu, J., Holtzman, D. M., & Mach, R. H. (2011). Sleep deprivation differentially affects dopamine receptor subtypes in mouse striatum. Neuroreport, 22(10), 489-493.

Oishi, Y., & Lazarus, M. (2017). The control of sleep and wakefulness by mesolimbic dopamine systems. Neuroscience research, 118, 66-73.