PIP News

Dreams, Nightmares, & Mental Health

At the end of October, with all of the spooky themes and Halloween fun, it seemed like a good time to talk about dreams, nightmares, and how sleep plays into our mental health.

It is generally recommended that adults get between seven and nine hours of sleep a night. During the time we are asleep, our brain “cycles” through different sleep phases, one of which is REM (rapid eye movement). This is the part of the cycle where dreams and nightmares occur.

One full sleep cycle, on average, lasts between 90-110 minutes as we shift between shallow and deep sleep. Interestingly, REM sleep takes up more of each cycle as the night goes on, with the longest periods taking place in the final hours of the night. That’s why, if we don’t get a full seven to nine hours, we are likely missing out on some of the most important hours for our mind to dream.

Function & Benefits of Dreaming

Dreaming is a healthy part of our sleep cycle, used for several functions including building memory, processing emotions, and determining which information to keep and which to discard. Another function of dreaming is to process situations, both those that already happened and those that may be coming up (i.e. dreaming about a test that you have the next day).

In a very interesting piece of research, Dr. Matthew Walker, author of Why We Sleep: Unlocking the Power of Sleep and Dreams, refers to dream sleep as “healing sleep” and “overnight therapy.” He suggests that during REM sleep, our brains are clear of the stress chemical noradrenaline. As such, in a dream state, our brains are in a safer space to re-process upsetting information and heal (Walker, M. P., & van der Helm, E. (2009).

Additionally, there are also categories of dreams. Some of these include “day residue”, which is simply an influence of the previous day’s sensory intake. “Lucid dreams” where people are aware they are dreaming and can actively control what happens next (i.e. fly where you want in your dream). Also, recurrent dreams are very common, often related to stress or anxiety. These may include teeth falling out, being naked in public, being late/unprepared, falling, or being unable to get away from danger.

So, What About Nightmares?

Nightmares are categorically different from dreams in one key way—how it affects our sleep cycle. While a dream is a healthy part of the sleep cycle that we wake from naturally, a nightmare disrupts the sleep cycle by waking us up. An occasional nightmare is not a cause for concern. However, nightmares can become problematic if they regularly interrupt our sleep cycles, make it difficult to go back to sleep, and/or create sleep avoidance.

Nightmares can be very distressing, particularly if they are frequent and disruptive to your sleep patterns. If you are encountering regular nightmares it is important to realize that they are treatable. Nightmares can be caused by many things including illness (depression, anxiety, PTSD) or may be medication-related. Treatment for nightmares can be discussed with your doctor and may improve through talk therapy with a counselor.

How to Improve Sleep, Dreaming, and Reduce Nightmares

While it sounds simple, the short answer to improving sleep, healthy dreaming, and reducing nightmares is to get more healthy sleep. Many people are sleep deprived for a variety of reasons and getting on a regular sleep schedule can solve a lot of those challenges. As a quick suggestion, to improve sleep, sleep hygiene is one of the easiest changes to address. This may include making sure you are sleeping at room temperature that is a couple of degrees cooler than your waking hours, going to sleep and waking at the same time each day, avoiding the use of artificial light at night (no phones!), and reducing the use of drugs and alcohol.

While the scientists of sleep and dreaming admit there is still much to learn, what we know for sure is that dreaming is good, healthy, and helpful for our physical, emotional, and mental health. Go, get some sleep, and dream on.


Walker, M. P., & van der Helm, E. (2009). Overnight therapy? The role of sleep in emotional brain processing. Psychological Bulletin, 135(5), 731–748.

October 31, 2022. By Anne Rulo, Author, Speaker, Therapist. FB/IG/Twitter @annemrulo 

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