Why do I Sometimes Remember my Dreams Vividly and Other Times Not at All?

Although you probably dream every night, it may seem like you seldom remember your dreams after waking up. Studies indicate that most people go through rapid-eye movement (REM) — the stage of sleep when most dreaming is thought to occur — four to six times during a full night's sleep, meaning that the average person over the age of 10 can have at least this many dreams. Most are forgotten, however. Scientists who study dreaming believe that people are more likely to remember dreams that involve strong emotions or events that a person might consider important when awake. When you don't remember your dreams, it's likely because they simply aren't very interesting.

Studies of dreams have found that many of the dreams people have deal with everyday situations that are not particularly memorable. Since most people have multiple dreams every night, the commonplace ones may simply not be distinct enough to stand out. Most people don't remember every single detail of every moment of their lives; usually, only those experiences that are actively remembered and/or which elicit an emotional response really stick in the memory. The same may be true with dreams: people seem much more likely to remember very strange, distinctive, frightening, or otherwise emotionally charged dreams, just as they would with real life experiences.

When people wake up during REM sleep, they are more likely to remember their dreams. Although this is not the only stage of sleep during which dreams occur, it is one of the most common. During dream studies, this is when subjects are often woken and asked about their dreams, since they are fresh in the mind. There is evidence that people can also dream during the more active stage at the end of sleep, in the hour or two before waking. Interesting dreams during this time may also be more easily remembered.

People who take certain medications — and some types of illegal drugs — often report having more dreams as well as ones that are more vivid. Certain drugs, like marijuana and cocaine, cause users to experience less REM sleep, and therefore have fewer dreams. When the drugs are discontinued, the body may increase the amount of time spent in the REM stage, and dreams may become more common and memorable.

Drugs that affect brain chemistry can also impact dreams. Varenicline, which is a prescription medication used to help people stop smoking, includes a warning about strange dreams and nightmares in its side effects, as do many antidepressants. Some studies suggest that, once antidepressant medications begin to work, many people's dreams become more positive, with fewer aggressive or unfriendly characters in them. L-dopa, a drug that increases the neurotransmitter dopamine in the brain, is known to cause patients to have more bizarre and vivid dreams, often with more emotional content as well.

No one really knows for certain why people dream, although there are many theories. Some people have argued that dreams help people solve problems or compensate for parts of the personality that aren't fully developed while awake. Others suggest that they help an individual process the day's events or "clear out" the mind after a busy day. Many modern researchers believe that dreams have no real "purpose" at all, although they do seem to have meaning; in other words, although there may be no physical or psychological reason why people dream, those dreams can reveal a great deal about the person who has them. Stress and anxiety can often affect the content of dreams, as can romantic feelings and other interests.

Dreams seem to be connected to specific networks of nerves in the brain that develop over time; sleep studies reveal that children under the age of 10 seem to dream less frequently than older people, suggesting that these networks are still maturing. It seems likely that some people may simply not dream much or at all, even during REM sleep, and therefore don't have many dreams to remember. Injuries to certain parts of the brain can also prevent a person from dreaming, and these people seem to be as healthy mentally as the average person, even without dreams. Dreaming may simply give the mind something to do as people sleep, helping them to stay asleep.

The easiest way to increase your ability to remember dreams is to want to remember them. If you believe that dreams are merely random brain stem activity, you have no real incentive to train yourself to remember the details of what you dreamt the night before. Just like actively trying to remember something while awake can help you memorize it, the desire to remember what you dream and a faith in your ability to develop this skill are crucial to success.

Experts recommend that people who want to remember their dreams more accurately keep a dream journal. Place a small notebook and pen beside your bed; then, when you first wake up, immediately write down as much of your dreams as you can remember. Don't worry about trivial things like spelling, grammar, or sentence structure — simply write down as much as possible, even if it's just a few words, phrases, or images. If writing proves too difficult, you can try drawing a quick sketch or supplementing your notes with a small tape recorder. After two or three weeks of this practice, you'll likely find that you can recall your dreams with a much greater frequency.

If you are bothered by a dream and want to increase your chances of remembering the specific details, try drinking several glasses of water before bedtime. This will often cause you to wake up in the middle of the night, disturbing your sleep cycle. When you awaken to use the restroom, spend some time writing in your dream journal while your mind is still focused on the details of your dream.

Many people who are interested in dream interpretation recommend that you make a habit of rereading your dream journal before bed each night. This will often make it easier to remember dreams that are related. Although there is debate about whether or not the symbols in dreams mean the same thing to different people, you may also wish to use a dream interpretation dictionary to look up possible meanings for specific images or thematic elements within your dream. This may offer new insight into the issue at hand, whether your dream is about a failed romance or work-related anxiety.