What Is a Dream?
The frequency of dream recall may vary or even fade at points in one’s life. A dream is a series of thoughts, images, or sensations that occur in the mind during sleep. It is a function of the brain. Dreaming may occur as specific regions of the brain are activated through sequenced electrical patterns and chemical activity. Vivid dreams—like a movie that occurs with you as the actor—are associated with rapid eye movement (REM) sleep. This state of sleep was first discovered by William Dement, MD, PhD, considered the father of sleep medicine. REM is associated with intense activity within the brain. In fact, the brain uses as much energy (and glucose) in REM as it does during wakefulness. The muscles controlling the eyes are active, as is the diaphragm that is responsible for breathing. The rest of the body’s major skeletal muscles are paralyzed during this state. This prevents the acting out of dreams from occurring (and abnormalities of its regulation account for both sleep paralysis and REM sleep behavior disorder). It is possible to experience fragmentary dreams in non-REM sleep. This includes the lighter stages of sleep (called stage 1 and stage 2) and slow-wave sleep (called stage 3). It is believed that the dream content of non-REM is more simplistic. It may be the dream of an image, an idea, or a concept that is more static. If REM-related dreams are a movie, non-REM dreams may be likened to a photograph. The nature of dreams and their specific meaning has been a subject of interest for millennia. The famous neurologist and founder of psychiatry, Sigmund Freud, explored the topic in his seminal work from 1900, The Interpretation of Dreams. There is no consensus on the scientific basis for the interpretation of dream content. Reflection and derivation of meaning may be best reserved as a personal exercise.
Normal Patterns of Dreaming
It is normal to dream, but it is common to not recall the dreams that occur. The dreaming state can be identified by measurements made as part of a diagnostic polysomnogram, including the recording of the:
Electroencephalogram (EEG)Ectrooculogram (EOG)Electromyogram (EMG)
The tell-tale signs of REM sleep include an active brain, rapid eye movements, and a loss of muscle tone. REM sleep occurs at intervals throughout the night. The first period of REM may be 90 to 120 minutes into the night. If it occurs early, in less than 15 minutes, this may be a sign of narcolepsy. REM periods become more prolonged towards morning. As a result, the last third of the night may include mostly REM sleep. It is common to wake in the morning out of the last period of REM. Just because they are not recalled, the dreams associated with REM sleep are likely still occurring. There may be variability night-to-night and across the lifespan.
Why Dreams May Be Forgotten
There are a few possible explanations for dreams that cannot be remembered. Some of these reasons include:
Less REM Sleep
First, it is possible that REM sleep is not occurring (or at least not occurring as much as normal). Medications may suppress REM sleep. In particular, antidepressants seem to have a powerful influence by delaying the onset or reducing the amount of REM sleep. Alcohol may also act as a REM sleep suppressant, at least until it wears off. If REM sleep is occurring, the vivid dreams that are associated with it may not be recalled. If there is a transition from REM sleep to another state of sleep (most often stage 1 or stage 2), prior to recovering consciousness, the dreams may be forgotten.
Dreams Often Fade Upon Waking
As a general rule, dreams fade quickly after waking. The electrical signals and chemical signatures that constitute the experience of the dream may disappear as wakefulness ensues, like a message written on a fogged mirror that vanishes as the steam evaporates. It is possible for elements of the dream to be recalled later in the day, perhaps triggered by an experience that reactivates the same area of the brain that created the dream overnight. Particularly memorable dreams may create an impression that persists for decades. Recounting the dream to another person may help to stabilize the memory. Dreams (or nightmares) that are associated with intense emotions, including fear, may also stick in the mind. The amygdala is an area of the brain that may help to elicit these emotion-laden dreams.
Sleep Disorders
Sleep disorders may impact dream recall. Untreated obstructive sleep apnea may also contribute to fragmented REM sleep as disturbed breathing occurs due to relaxation of the airway muscles. For some, this may lead to increased dream recall (including dreams of drowning or suffocation). Sleep apnea may likewise lead to REM sleep deprivation and effective CPAP therapy may cause a profound rebound of REM sleep. People with narcolepsy also experience sudden sleep transitions that contribute to dream recall, sleep-related hallucinations, and sleep paralysis. Poor sleep habits, stress, and psychiatric conditions may also fragment sleep and increase dreaming and recall.
How to Better Remember Dreams
If you are interested in improving your dream recall, consider a simple change: keep a dream journal. By keeping a pen and a notebook on the nightstand next to the bed, it becomes easy to quickly record dreams immediately upon awakening, before they have had a chance to fade. Writing down your dream may encourage improvements in dream recall. If the scribbled notes can be interpreted later in the morning, it may be possible to reflect on the meaning of your dreams.
A Word From Verywell
Dreams are a fascinating part of sleep. Though you may feel distressed by not remembering dreams, rest assured that this state of sleep is likely still occurring. The benefits yielded, from memory processing to learning and problem solving, are likely just below the surface of awareness. As you fall asleep, imagine a world that might be, and it may come to you in the night.
