Teacher Area

Sleep & Dreams Factoids
Mix and Match

Grades: 7-12.  Subjects: Health, Science, Psychology


Given common questions and scholarly answers about sleep and dreams, students seek to correctly match the two. In so doing, students get a broad overview of information about sleep and dreams.


  • Large cards (8 ½ x 11" card stock sheets work well; it helps to have half in one color and half in another)

  • Marker


  1. Pre-class preparation is necessary. Clearly label 46 separate cards with the questions and answers that follow, omitting the extended explanations. (If you are using two colors of cards, put all the questions on one color, and all the answers on the other, to make the task somewhat easier for the students.)

  2. This activity can be implemented in three different ways, depending upon the group size and your own inclination. Either distribute the 46 cards individually (one card per person), OR give 23 participants the questions, and put the answers in a pool in a central location, OR arrange the cards in two pools (one for questions and one for answers) in a central location and ask the participants to work as a group. (Of course, you may remove pairs of cards to make the number better match the number of your group.)

  3. Instruct the participants that the cards contain scholarly information about sleep and dreams, which need to be paired together to form questions and answers. The group’s task is to match each card with its appropriate partner. They should match perfectly, with no questions or answers left over at the end.

  4. To make the activity livelier, you could set a time limit – say, five or ten minutes – to complete the task.

  5. As the group works, try to avoid giving hints unless they are having a particularly difficult time with the assignment.

  6. When the group is done, go through the cards one pair at a time, offering the extended explanations provided; you can read them aloud yourself, or let the pair of students who hold the corresponding cards read the information aloud to the class. (If when you turn your attention to a particular question or term, you find that the group has mismatched it with the wrong answer or definition, you might offer the group a second chance to find its mate before you reveal the correct answer.) Encourage discussion throughout.

Are there people who never dream?

Only in special, rare cases.

Dreams are most likely during a phase of sleep called REM (rapid eye movement) sleep. Even people who say they never remember dreams, usually do remember dreams when lab technicians wake them up during REM sleep. The main exception seems to be people with rare kinds of brain damage.

How many minutes does it take for the average, normal person to fall asleep?

15 - 20

Of course, this varies from person to person and from time to time. If you consistently fall asleep much faster (say, within 5 minutes, every single night), this could be a sign that you are overly sleepy. If you consistently take more than 30 minutes to fall asleep, you may have insomnia.

How many hours of sleep should young people (ages 11 – 17) get each night?


Research shows that young people your age don’t perform their best, and don’t awaken easily without an alarm clock, unless they get close to ten hours of sleep! Do you get enough sleep?

How many nightmares does the average young adult have in one year?


Some people have many nightmares. Others have none. (Psychological tests show that nightmare sufferers may be more open, sensitive, and trusting than other people.) The frequency of nightmares changes with age. Children aged 3-8 are particularly susceptible to nightmares. The once-a-month figure (above) comes from research on college students. Most nightmares are due to stress, illness, trauma, or physical discomfort.

How many dreams does the average person have in one night?

3 - 5

This is really a guess. But each night, we typically have 3 – 5 periods of REM sleep. And when scientists wake people up from REM sleep in sleep labs, most of them (80%) report that they were dreaming. The number could actually be much higher, since it is possible to report dreams from other sleep stages, too. But researchers say that it is probably impossible to remember all (or even most!) of your dreams, because your memory just doesn’t work the same way when you are asleep.

Do blind people dream?


The dreams of people blind from birth feature sounds, touches, emotions, etc. – just like their waking experience. (People who went blind after age 7 usually see some visual images in their dreams.)

Which animals dream?

All mammals (except the spiny anteater).

If you have a pet, you have probably seen the animal twitch in its sleep. All mammals experience REM sleep, and research suggests that during REM, they experience the same hallucinations that we humans call dreams. But different species go through the cycles of sleep at different rates. For instance, cats’ REM periods are only 24 minutes apart. Opossums’ REM periods are about 90 minutes apart, the same as ours.

Sleepwalking occurs in which type of sleep?

"Slow Wave" sleep / Delta sleep

Most sleepwalking happens during the deepest kind of sleep, Slow Wave Sleep (SWS). Contrary to popular opinion, it is not harmful to wake up a sleepwalker. However, it may be hard to do. (People are usually very hard to wake up from SWS.) Kids often outgrow sleepwalking, although the problem can linger into adulthood.

Do people dream in color?


People who pay more attention to color in waking life (artists, etc.) are more likely to notice the colors in their dreams. But even people who don’t normally notice color in their dreams are often able to recall specific dream colors under certain circumstances (awakened during REM in a sleep lab, and asked specific color questions by the technician.)

Is it true that if you die in your dream, you’ll die in real life?


It is a common superstition, but a false one. Many people do wake up from dreams or nightmares just before the unavoidable death of their dream-self. Even in our dreams, we have a strong survival instinct; many peoples’ dreaming minds simply will not allow the dream to continue if death seems certain. But some people do dream of their own death and live to tell about it.

What percentage of American adults say that they have had a psychic dream?


Reports of psychic dreams are amazingly common. Scientists often attribute the reports to chance or coincidence. But those who have experienced these dreams staunchly believe in psychic phenomenon. What do you think?

How many major religions have teachings that include Divine/spiritual dreams?


The Bible mentions quite a few important dreams, as do the sacred texts of all major world religions. Most religions teach that:

  1. Dreams can be a way of communicating with a Higher Power.
  2. Not all dreams should be regarded as messages from God.

What does your religion teach about dreams?

What do the following have in common? Pregnancy, psychological trauma, natural awakening (without an alarm clock)

Increase dream recall

People who have been through traumatic experiences such as rape, wartime combat, or natural disasters, usually notice that their dream recall increases sharply. The hormonal changes (and/or lighter sleep) of pregnancy also seem to boost dream recall. Some medications can cause a sudden surge of dreams. You are much more likely to remember dreams if you wake up naturally and have an unhurried morning.

What do the following have in common? 
Bright lighting, warm temperature, cold feet, caffeine, stress

Worsen sleep

Even with your eyes closed, some light gets through your eyelids and sends a subtle "wake-up" signal to your brain. When the room is hot, it may cause nightmares. Studies show it takes longer to fall asleep when your feet are cold. Some people feel that caffeine does not affect them much, since they can still fall asleep. But research shows that the quality of caffeinated sleep probably isn’t as good; there are more arousals and restless movements. Caffeine can stay in your system and affect your sleep for 6 hours.

What do the following have in common? 
Waking up at the same time every day, milk & turkey near bedtime, regular "white" noise

Improve sleep

People who maintain very regular schedules of bedtime and awakening times tend to sleep better. Milk and turkey contain an amino acid called tryptophan, which may improve sleep. Some light sleepers benefit by listening to a very constant noise (such as an electric fan), which may help cover up irregular background noises that might otherwise wake them up.

What do the following have in common? 
Alcohol, marijuana, depression

Decrease dream frequency

All of these affect REM sleep, and suppress dreams. Oddly enough, some people may actually feel they dream more after having alcohol, for example. Why? Because when our bodies are deprived of REM sleep, they eventually go into "REM rebound", an intense REM state that tries to "make up for lost time" in that sleep stage. The resulting dream may be more memorable (and/or more disturbing!), but in reality, the body is still not getting enough REM sleep time.

What do the following have in common? 
Loss of creative thinking, irritability, slower reaction times, difficulty learning new skills

Effects of sleep deprivation

It really is a bad practice to pull "all nighters" before important exams. It affects the way your brain works, and also may affect its ability to store knowledge in an orderly way for long-term retrieval. Your creative thinking and your good mood are usually the first things to suffer!

What do the following have in common? 
Feel awake but unable to move, may sense an "evil presence" in the room, may struggle to breathe

Symptoms of sleep paralysis (also called an "Old Hag" experience)

People have been describing this phenomenon since ancient times. Scientists have a theory about why it may happen. Ordinarily, during dreaming sleep, our brain sends a chemical message that paralyzes our body (which protects us from acting out our dreams and getting into a lot of trouble!) But sometimes, for unknown reasons, something goes wrong and this protective paralysis doesn’t go away when we first wake up. It’s as if it takes our brain a minute to realize that dreaming sleep has ended. The hallucinations of dreams may continue, too, resulting in visions of evil creatures. Why are the visions almost always scary? Because it is very scary to feel helpless and paralyzed, which may trigger us to imagine scenes of malevolent spirits.

What do the following have in common? 
Asleep, dreaming, aware that the dream images are dreams, may include ability to control the dream

Characteristics of lucid dreams

During ordinary dreams, we are not aware that the experience is actually a dream. No matter how strange or bizarre the dream becomes, we usually believe it to be real and act accordingly – that is, until we wake up and realize our error! In lucid dreams, the dreamer suddenly thinks, "Hey – right now I am dreaming all of this!" Sometimes, this awareness dawns during a nightmare. We try to make ourselves wake up to end it. Some people (including sects of Tibetan monks) try to cultivate this mental state.

What do the following have in common? 
Loud and irregular snoring, daytime drowsiness, intermittent pauses in breathing during sleep

Symptoms of sleep apnea

Sleep apnea is a potentially life-threatening breathing disorder that occurs during sleep. It is about as common as adult asthma. It is usually treated with a special breathing mask that is worn during sleep.

What do the following have in common? 
Jerking in sleep, discomfort in limbs at sleep onset, daytime drowsiness, difficulty falling asleep

Symptoms of movement-related sleep disorders

Restless Legs Syndrome (RLS) and Periodic Limb Movement in Sleep (PLMS) are movement-related sleep disorders. Sufferers kick and jerk a lot at night, often rhythmically, and may experience great discomfort or "restlessness" of the limbs (especially legs) at night.

What do the following have in common? 
Muscle weakness (especially with emotion), severe daytime drowsiness, hallucinations on the borders of sleep, sleep paralysis

Symptoms of narcolepsy

Narcolepsy is a relatively rare sleep disorder, but it often has a profound effect. People with severe narcolepsy may fall asleep in the middle of a sentence, or may drop to the ground during laughter or tears. The onset of symptoms usually occurs during adolescence or early adulthood.

What do the following have in common? 
Acting out violent dreams, thrashing or moving about in the bed primarily toward the early morning hours.

Symptoms of REM sleep behavior disorder (RSBD)

Although it may be mistaken for sleepwalking, RSBD is actually very different. It is a disorder of REM sleep in which the normal muscle paralysis of REM does not function properly. Unfortunately, aggressive or violent dreams seem to be a part of this syndrome, so it may lead to serious injury for the sleeper or his/her bed partner. It occurs more often (although not exclusively) in elderly men who have other neurological problems.

Possible Extensions

If the students were all given individual cards, have them do independent research on the concept addressed by their own card, and report back to the class at a future time.

Ask the students if they still have any unanswered questions about sleep and/or dreams. Challenge them to discover for themselves the answers to these questions, being sure to consult scholarly and/or scientific sources in their research.