The answer depends on how long we move through the sleep cycles. Dreams can last for a few seconds or they can last for up to two hours. They feel longer because our brain works differently when we're sleeping than when we're awake!
If you feel that your dreams last for so long it's a good sign you're entering the REM phase of sleep many times during the night. This is a good sign, although it may feel a little exhausting if your dreams are bombarding you with messages.
Sometimes, dreams seem so real and vivid, but how can we explain why our dreams feel so vivid and realistic? There are several factors that can contribute to this phenomenon, including being active in REM sleep, hormones and neurotransmitters, stress, anxiety levels, age and sleeping cycles.
Despite this common belief about how we dream, time in dreams actually is not compressed. If you dream of an activity that would take five minutes in waking life, you probably dream about it for a full five minutes.
Watson, MD, even if you fall asleep as soon as you lay down, it'll still take you between 70 and 90 minutes to start dreaming. Additionally, sleep comes in cycles, he says, and this happens in two overarching phases: non-REM sleep and REM sleep—and REM sleep is typically when dreaming occurs.
The length of a dream can vary; they may last for a few seconds, or approximately 20–30 minutes. People are more likely to remember the dream if they are awakened during the REM phase.
Researchers estimate that the average person spends about two hours dreaming each night. REM sleep periods early in the night generally last about 10 minutes and gradually increase in length throughout the night to a maximum of about one hour.
“Since dreams are thought to primarily occur during REM sleep, the sleep stage when the MCH cells turn on, activation of these cells may prevent the content of a dream from being stored in the hippocampus – consequently, the dream is quickly forgotten.”
REM Sleep. 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, you may forget your dreams.
Indeed, the longest recorded period of REM (dreaming sleep) is one of 3 hrs 8 mins by David Powell (USA) at the Puget Sound Sleep Disorder Centre, Seattle, Washington, USA on 29 April 1994.
Although some theorists have suggested that pain sensations cannot be part of the dreaming world, research has shown that pain sensations occur in about 1% of the dreams in healthy persons and in about 30% of patients with acute, severe pain.
tl;dr. Vivid dreams are dreams that feel like they're happening IRL. They can be good dreams (even sex dreams!) or nightmares. Sometimes they just happen, but other times they're caused by stress, anxiety, sleep disorders, medications, or pregnancy.
Sometimes the ordinary stresses of daily life, such as a problem at home or school, trigger nightmares. A major change, such as a move or the death of a loved one, can have the same effect. Experiencing anxiety is associated with a greater risk of nightmares.
Even though some dreams only last for a few minutes, we might spend up to four hours of a full night's sleep dreaming. Again, this varies depending on how well we are sleeping and how long we're asleep.
Waking up Crying From a Dream
The sensations you feel while sleeping and the emotions you experience before bed may cause you to wake up crying. If you wake up crying from a bad dream, that is your body's response to the weight of the suppressed emotion.
That's because they get weirder the longer you sleep for, scientists reveal. If you've ever woken up bewildered by a dream you were having, there's now an explanation as to why. Scientists have discovered our dreams really do get weirder as the night goes on.
The answers to these questions may lie in the way our memory system develops as we grow from a baby to a teenager and into early adulthood. Our brain is not fully developed when we are born—it continues to grow and change during this important period of our lives. And, as our brain develops, so does our memory.
It's unlikely that people never dream. It's far more likely to have issues with REM sleep, memory recall, or other sleep disturbances. Certain substances, such as caffeine, alcohol, benzodiazepines, and psychiatric medications, may affect REM sleep, which may impact dreaming.
If you are having weird dreams, it may be due to stress, anxiety, or sleep deprivation. To stop having weird dreams, try managing stress levels and sticking to a sleep routine. If you wake up from a weird dream, use deep breathing or a relaxing activity to fall back asleep.
“When a runner dreams about that, it typically means that they are feeling inept, inferior, slowed down, etc., at the time of the dream,” she explains. “Perhaps, a marathoner dreams about running slowly. They may be releasing the fear of losing their speed.
In most cases, not being able to remember your childhood very clearly is completely normal. It's just the way human brains work.
You can have several—even a dozen—dreams in one night. It's not just one dream per night, but rather dozens of them, say experts—you just may not remember them all. "We dream every 90 minutes throughout the night, with each cycle of dreaming being longer than the previous," explains Loewenberg.
Overall, researchers and study participants agreed that black and white dreams were the norm, and rare cases of coloured dreams were dubbed 'Technicolor' dreams (Calef, 1954, Hall, 1951), highlighting their perceived artificiality. This tendency to report black and white dreams suddenly disappeared in the 1960's.
Such feats of dream manipulation may not seem possible to the same extent in our real lives, but they are not altogether absent. In fact, a number of people are able to experience something called lucid dreaming, and some of them are even able to control certain elements of their nightly dreams.