At times, dreams may occur during other stages of sleep. However, these dreams tend to be much less vivid or memorable. 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.
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.
Most dreams only last about 10 minutes on average (give or take a few minutes), but inside the dream itself it often feels, subjectively, like much more time has passed. Some parts of the brain which are responsible for our logic and reasoning are suppressed when we dream.
We dream most vividly during Rapid Eye Movement (REM) sleep
REM sleep occurs in short episodes across each night each about 90 minutes apart. Our longer dreams are in the morning hours.
Dreams last as long as we're asleep; it's caused by our thoughts looping back into our mind. The reason why they may seem to last only 2 or 3 seconds is because our perception of time may be hindered by this phenomena.
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.
Older studies found that when given a choice between two answers, most people were able to accurately say how long their dreams had lasted. Subsequent studies also found that dream time seemed to be equivalent to real time. There may be exceptions, however.
Most experts believe that lucid dreams are the rarest type of dreams. While dreaming, you are conscious that you are dreaming but you keep on dreaming. According to researchers, 55 percent of people experience these types of dreams at least one time in their life.
In REM sleep, our brain activity is near waking levels, but our body remains "asleep" or paralyzed so we don't act out our dreams while lying in bed. Since our brain is so active during this stage, it can sometimes scare us into waking up, essentially.
That said, this is not a hard rule and exceptions can occur. 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.
So, why do my dreams sometimes feel so incredibly real? It comes down to how intensely stimulated parts of the brain become during REM sleep. Coupled with the powerful emotions we're experiencing within them at the same time – creating an illusion that feels more life-like than reality itself!
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.
“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.”
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.
Even though you may “see” a text in a dream, it's unlikely for it to actually be written in a language you know or even to exist at all. The things we think we read in our dreams are actually just our own thoughts projected in your subconsciousness, so sadly, you can't read in dreams.
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.
While recurring dreams and disorienting dream loops are common during lucid dreams, it is not possible to get actually get stuck.
Dreams can be so realistic that it can be hard to tell if we're awake or asleep. And sometimes, we wake up in the middle of a dream and wonder if it's possible to go back to sleep and pick up where we left off. It is possible to resume a dream, but it requires a certain focus and concentration.
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.
1. Falling. The most frequent in the common dream family, researchers say that the average human will dream about falling to his or her death more than five times in their lives (yikes).
While every human being so far as we know exhibits REM sleep, not every human being reports dreams. It appears you can have REM sleep with very low dream recall or possibly without dreams entirely. There may even be groups of individuals who never recall their dreams or who do not dream.
Researchers demonstrate that during REM sleep, people can hear—and respond to—simple questions such as “What is eight minus six?” Dreams are full of possibilities; by drifting into the world beyond our waking realities, we can visit magical lands, travel through time and interact with long-lost family and friends.
“Dreams are often about identity, because we're figuring out who we are and what we need, and the beliefs and perspectives we hold,” says Wallace. “If you feel unfulfilled, undervalued or not the person you want to be in waking life, your dreams will often reflect that.
“Slow running could be a representation of a feeling of being held back or hindered in some aspect of life,” he explains. “It's also possible that the slow running could be related to a sense of fear, as the brain can interpret feelings of danger as physical sensations, such as not being able to move quickly.”