Understanding Rem Sleep And The Lack Of Dreams

Dreaming is a normal and healthy part of the sleep cycle, but why do some people not remember their dreams? Dreams occur during the REM (rapid-eye-movement) stage of sleep, which is characterised by increased brain activity, irregular breathing, and a temporary loss of muscle tone. While dreams can occur during any stage of sleep, the vivid dreams that people tend to remember happen during REM sleep.

During REM sleep, the brain is highly active and dreams are more fantastical, bizarre, and vivid. However, not everyone will remember their dreams, and this could be due to various factors. For instance, the use of certain medications and substances, such as opioids, benzodiazepines, and antidepressants, can suppress REM sleep. Additionally, sleep disorders like sleep apnea can also disrupt REM sleep.

Furthermore, the amount of REM sleep an individual gets can be influenced by their sleep schedule, physical activity, exposure to electronic devices before bedtime, and their diet. Therefore, not remembering one's dreams could be attributed to a combination of factors affecting the quality and duration of REM sleep.

REM sleep is important for brain development, memory consolidation, and emotional processing

Brain Development

Newborns spend most of their sleep time in REM sleep. This is because REM sleep promotes brain development, especially in newborns with less developed brains, such as humans and puppies.

Memory Consolidation

During REM sleep, the brain processes new learnings and motor skills from the day, committing some to memory, maintaining others, and deleting the rest. This is known as memory consolidation. Studies have shown that people who achieved REM sleep during a nap were better able to judge facial expressions afterward.

Emotional Processing

REM sleep is important for processing emotions, especially fear-related ones. The amygdala, the part of the brain that processes emotions, activates during REM sleep. Studies have found that people who spent more time in REM sleep had lower fear-related brain activity when they were given mild electric shocks the next day.

Dreaming may be a way for the brain to process and store information

The ability to engage with and rehearse feelings in different imagined contexts may be part of the brain's method for managing emotions. Dreaming could be the brain's way of "straightening up", clearing away partial, erroneous, or unnecessary information.

Dreams may also be a form of distorted instant replay in which recent events are reviewed and analysed. However, the true function of dreams remains poorly understood and is the subject of ongoing scientific investigation.

Lack of REM sleep can cause fatigue, irritability, and changes in mood and memory

Sleep is essential for our health and overall well-being. However, many people do not get enough sleep, which can have various health consequences, including fatigue and irritability.

Rapid Eye Movement (REM) sleep is the fourth stage of sleep, characterised by relaxed muscles, quick eye movement, irregular breathing, elevated heart rate, and increased brain activity. During this stage, we experience vivid dreams, and our brain processes emotions and consolidates memories. While REM sleep typically makes up 20-25% of our total sleep time, a lack of it can lead to several issues.

Fatigue

A lack of REM sleep can cause fatigue and sleep deprivation, affecting your ability to stay awake and concentrate during the day. You may find yourself nodding off or experiencing "microsleep episodes", where you briefly fall asleep during the day. This can impact your work, family life, and even make activities like driving dangerous.

Irritability and Changes in Mood

Inadequate REM sleep can also lead to irritability and changes in mood. Studies have shown a relationship between REM sleep disruptions and certain types of depression. The dream self is rated more negatively than the daytime self after REM sleep awakenings in individuals with depressive and anxious tendencies. Furthermore, a lack of REM sleep can affect the brain's ability to regulate emotions, leading to increased irritability and negative mood states.

Memory

REM sleep plays a crucial role in memory consolidation, where the brain processes and stores new information and skills learned during the day. A lack of REM sleep can result in forgetfulness and impaired memory function. Studies have found that people who achieved REM sleep during a nap performed better on memory tasks than those who didn't, highlighting the importance of this sleep stage for memory consolidation.

In summary, getting enough REM sleep is vital for our health and well-being. A lack of REM sleep can lead to fatigue, irritability, changes in mood, and memory issues. Ensuring adequate sleep, including sufficient REM sleep, is essential for maintaining optimal physical and mental health.

Sleep disorders and substance use can impact REM sleep

The way the brain regulates REM sleep is not yet fully understood, and researchers continue to find that different drugs can trigger a wide range of sleep-related symptoms. For example, while benzodiazepines are often used to treat REM sleep behaviour disorder, they may make symptoms worse in some individuals. People with RBD sometimes experience initial symptom relief from drugs that suppress REM sleep. However, substance use generally degrades sleep quality and can cause insomnia or other sleep disorders.

Alcohol, for instance, can suppress REM sleep, causing people to wake up after a full night of sleep feeling like they hardly slept. It can also make people more restless during sleep and prone to vivid nightmares and RBD symptoms. Marijuana can also cause sleep disruptions for people with sleep disorders, reducing sleep quality. While this can initially decrease episodes of acting out dreams, it often has a backlash effect, causing symptoms to re-emerge and become more severe over time.

Stimulants such as caffeine, prescription drugs like Adderall, and synthetic drugs like bath salts are also known to suppress sleep. People with insomnia, RBD, or other sleep disorders may abuse stimulants to stay awake during the day after a poor night's sleep, leading to a negative cycle of worsening sleep quality.

Certain antidepressants can also suppress REM sleep, and it is recommended that people with comorbid RBD and depressive disorders work with physicians to find alternatives to common antidepressants or use other treatment strategies.

You can increase REM sleep by keeping a regular sleep schedule and limiting screen time

REM sleep is the fourth and final stage of the sleep cycle, characterised by rapid eye movement, relaxed muscles, irregular breathing, an elevated heart rate, and increased brain activity. It usually occurs about 60 to 90 minutes after falling asleep and is associated with dreaming, memory consolidation, emotional processing, and brain development.

Keep a Regular Sleep Schedule

Keeping a consistent sleep schedule is crucial for ensuring you get adequate REM sleep. Aim to go to bed and wake up at the same time every day, even on weekends. Irregular sleep patterns can disrupt your physical and mental health and increase the risk of diabetes, heart failure, and depression. Maintaining a stable sleep schedule helps prime your body for sleep and waking, allowing you to get the recommended seven to nine hours of sleep necessary for optimal REM sleep.

Limit Screen Time

Excessive screen time, especially close to bedtime, can interfere with your sleep quality and REM sleep duration. The blue light emitted by electronic devices can suppress melatonin production, disrupting your sleep. Power down electronics at least an hour before bedtime to give your mind a break from the stimulation and help you wind down. Keeping gadgets and screens out of the bedroom creates a soothing environment conducive to sleep and enhances the likelihood of achieving REM sleep.

Frequently asked questions