What did you do last night? A commonly asked question, which usually elicits some pretty commonplace answers, even in the hip college environment of Wesleyan University. "I went to the movie at the CFA," "I caught the dance performance at Crowell," "I saw the bands at WestCo." Even if this standard greeting led to slightly more shocking responses, "I enjoyed my dinner at Mocon," it is not likely that one would doubt the sanity of the person recounting the activities of the previous evening. It is even less likely that such a prosaic inquiry would lead to numerous experiments, hours of research, and several controversial theories in scientific fields ranging from psychology to neurobiology. What could any human do that would provoke so much curiosity, amazement, and scientific study?

Well, when one Wes student (who will remain unnamed in order to protect his, or her identity) was asked this question, She (or he) responded:

Well, I took the bus to Mars, and when I got there, all the bars were closed. I decided to go to Jupiter to see my grandfather. But just before I got back on the bus, It turned into a comet. I looked at the moon which was actually a gigantic clock and it was kind of late. So I jumped on the comet and came back home.

This anecdote immediately met with some stares, scowls, and other assorted looks of astonishment and confusion, as well as a few accusations of drug abuse. But not even the wildest Eclectic party could match that night. In fact no party on earth could ever live up to this story. The fact is that this did not take place on earth (but it didn't take place on Mars either). Are you beginning to understand? Maybe you should sleep on it.... Because if you do, you will most probably be whisked away to your own tale of adventure and fantasy, more commonly known as a dream.

Although we often share our dreams and speculate about their meaning, few people ever question why or how we make these fantastical nightly journeys. Dreams are seldom ignored, but dreaming, the act itself, has come to be an accepted part of life which few people question, despite how little is really understood about these nightly movies in our head. Personal investigations into out nocturnal voyages are more likely to be carried out along the lines of "Why did I dream this?", than "Why do I dream at all?" In this way, when it comes to dreams most people concentrate on symbollic content rather than the actual physiological process of dreaming.

This prevailing focus on content is reflected in research that is aimed at interpretation and understanding of dream objects and events. This research has led to many dream theories which focus on its psychological aspects, because as the eminent sleep researcher, Dr. J. Allan Hobson stated, "Dreaming is a psychological state, and if dreaming per se has a function, it is at the psychological level."¹

The most popularly known of these theories remains that posited by Sigmund Freud. The basis of Freud's theory revolves around his idea of the human psyche consisting of distinct parts, each with distinct functions. Freud viewed dreams as a way to accomplish the desires of a somewhat primitive part of the human mind. This "wish fulfillment" is what acts as the guiding force in our dreams. Dreams are merely attempts to satisfy these unconscious urges. Freud claimed that such thoughts were censored, due to their rudimentary nature, and took on disguised forms in our dreams. In this model, the objects and actions in dreams become symbols that could be read in order to decode the latent message linked to the unconscious. Thus, dreaming provided us with an opportunity to act upon these innate yet basic desires without experiencing the consequences of these actions.

More recently, dream theories have developed which remain in the realm of psychology, but have become less dogmatic in their understanding of dream function. These views claim that the individual's specific life experience and personality play a greater role in the function of dreams. Such theories also reveal that dreams may have a more adaptable and progressive function.

One such theory involves the interaction of a person's daily experience with those of his past. This angle claims that dreaming results as the attempt of the mind to integrate new experiences with ones held in our memory of the past. Dreams act as a method of comparison. We are able to view the day's events in light of our overall human existence. Dreaming offers a person greater perspective on the thoughts and actions they had while they were awake. A dreamer views life metaphorically, with the memory of previous events as a standard by which to judge and understand what has just taken place. This can be seen in an experiment that showed an increased amount of dreams involving earthquakes amongst people in the Bay Area, soon after the one that rocked San Francisco in 1989.² Dreaming organizes the activities of out lives and files them so that they can be easily comprehended and recognized in light of life itself.

Another theory claims that dreams create a space where people are able to, "master stressful situations occurring in their daily lives."³ J. Dallet dubbed this the "mastery" hypothesis.⁴ With this view of dreaming, the individual approaches dreaming as a way in which to conquer problems that he might encounter in real life. It is clear that stressors, or other sources of anxiety, are often the subjects of out sleeping thoughts. It is proposed that dreaming allows us to make an attempt to overcome problems. This can be seen in research gathered by G. Halliday at The Center for Individual and Family services. This study showed that people who are anxious about upcoming examinations, often have dreams about the anticipated event in which they pass the test.⁵ Such dreams clearly aid people in dealing with stressful situations.

We are capable of approaching a hardship, brainstorming how to defuse it, and then applying these solutions all within the safe confines of our heads. This approach may also be undertaken while someone is awake, but it is said to be more beneficial during sleep for several reasons. There is no way that thought can be interrupted because it occurs in an internally constructed scenario. This allows a dreamer to focus and follow through with a train of thought without having to be thrown off track. Also, there is no risk of committing a socially unacceptable act, thus we are given greater range of freedom in which to solve the problem. Additionally, there are no time, coherence, or space constraints, that might limit our actions.⁶ For these reasons, the liberties that characterize dreaming create a world in which a dreamer can take an experimental, yet hands on approach to removing burdens from their lives. Dreaming, in this "mastery" theory, is seen as a way to develop different perspectives that might not be thought of in the waking world.

Other hypotheses fall into the category of positive functional theories. This view of dreaming explores the idea that a dream is a workspace for the mind. It is similar to "mastery" theories except it is derived from a proactive as opposed to a problem solving approach. Supporters of this theory believe that dreams provide an opportunity to experiment with novel ideas and thoughts. Dream space is a chance to gain more experience. It is simply a way to learn more, to acquire a better sense of knowledge. Some experts have even offered evidence that links dreaming to the creative process, as seen with the tests and interviews compiled by Rosslyn Gaines. The established artists who took part in this experiment appeared to be "using their dreams primarily to understand their selves in greater depth."⁷

As stated before, studies attempting to decode dreams remain locked in the psychological realm. It is for these reasons that research done exclusively on dream content yields results that have to do with behavioral aspects of existence. On the psychological level, one theory is as good as the next, because they all fail to muster conclusive proof. No method has been developed, nor data ascertained that has led to the finding of the definitive function of dreams. Some scientists have gone so far as to state that dreaming may simply be entertainment for the mind as it sleeps. While this idea may seem laughable at first, it deserves as much attention as aforementioned theories. In fact, when looking at dreams from a physiological perspective, all theories of their function explain our nightly adventures as the brain trying to tell itself a story.

To be more accurate, physiological studies transform the question "Why do I dream?" to "How do I dream?" When shifting our attention from what we dream, to dreaming as a bodily process, it is also important to note that the focus moves from dream research, to exploring the functions of REM sleep. REM (The letters refer to the Rapid Eye Movement that takes place during this phase) sleep is the name given to the stage of sleep associated with increased brain activity and dreaming. It was discovered by Aserinsky and Kleitman in 1955.⁸ Although the two topics of REM and dreams do merge in sleep research , it is important to make this distinction for they belong to the separate realms of human physiology and psychology, respectively. Pure dream research is based upon content, while REM research focuses on the bodily processes that occur while we are dreaming. Unlike dream researchers, who mainly deal with the mind, scientist working with REM are more interested in how physical structures and functions interact and influence our minds during the dream-state.

The physiological actions that take place during REM sleep induce the sensation of dreaming. The part of the brain that is suspected to control REM sleep is located in the brain stem, specifically, the pontine geniculate occipital region. Signals from this area of the brain are, active throughout REM sleep, are also picked up by parts of the cerebrum. These signals, referred to as PGO waves, bombard many parts of the cerebrum, where much of the brain's sensory processing networks are located. These are the parts of the human brain that take the information from the outside world and weave it into a whole and accurate representation.⁹ In other words, these signals flood the regions of the brain that are responsible for making sense of the world. Thus, the PGO waves that stimulate REM sleep, also create the neural signals that the brain uses to formulate the input that weaves the fabric of dreams.

These more advanced brain systems literally drown in the deluge of this neural noise. These networks maintain the same purpose that they have when a person is awake. They still attempt to make sense out of the sensory input. So, as they are being bombarded with wave after wave of PGO signals, the cerebrum attempts to make sense out of this random bursts of nervous activity within the brain itself. Hobson refers to this as the activation-synthesis hypothesis of dreaming. "Activation is an energy concept."¹⁰ This refers to the switching on of certain neuronal circuits during REM sleep. "Synthesis is an information concept."¹¹ Activation-Synthesis describes the way that the brain synthesizes a dream from the internal relay of information.

The chemical environment of REM sleep causes an impairment of the rationale and ability to reason that greatly aids cognitive processes while a person is awake. The altered chemical states also lead to neural energization and the hallucinatory effect of dreams. This change in the chemical levels of the brain, combined with the peculiar qualities of the PGO waves, give dreams their bizarre nature. The brain, as always, is doing its best to find a coherent meaning in the series of neural signals that accompanies the onset of REM sleep. During this process of searching for meaning, it draws on various regions of the brain, utilizing the knowledge, thoughts, and experiences that are in your mind. "That's what your brain has to work with, your memories and associations,"¹² says Robert Stickgold, a neuroscientist at Harvard. It is due to this interaction that current problems, the past, and environmental stimuli sneak their way into our dreams.

Understanding this relationship between REM sleep and dreaming is vital. It is this link that exposes the psycho physiological nature of sleep research. Now that we have covered some possible explanations of dream function, and seen how dreams and REM sleep operate together, let us turn our attention to the physiological theories concerning the function of REM sleep.

Through their work with REM sleep Graeme Mitchison and Francis Crick postulated the theory of reverse learning. They claimed that, "REM sleep is involved in a form of cleansing operation in the cerebrum to get rid of spurious connections between neurons which inevitably arise in the myriad of neural networks during wakefulness"¹³ In this theory memories are stored in the creation of new neural pathways. Yet, through the course of even one day, a person is exposed to so much that might be consolidated as a memory in one of these paths, that some of it must be extraneous, that preserving such a connection would be useless. To prevent the brain from becoming overwrought with these pointless memories, REM sleep showers the brain with this series of neuronal bursts so that these superfluous nervous connections can be removed from our minds. The PGO waves erased the unneeded information that had been coded during the day. Now memory consolidation could take place more efficiently, according to this theory. Dreams were viewed as the record of these unwanted thoughts. In the words of the two researchers, "We dream to forget."¹⁴

Another theory that purports a purpose to REM sleep is that of the French professor Michel Jouvet. His work attributes the activity that accompanies REM sleep to the maintenance of certain behavioral patterns that are genetically coded. The pattern of nervous firing is said to be a rehearsal of such behavior that tests the ability to carry out these actions in a proper manner. "If any changes need to be made as a consequence of the animal's experience with real life," these can be accomplished during this testing phase, "and the appropriate recoding performed."¹⁵ This serves to insure that an action or series of actions that has proved to be vital to survival, has an outlet through which it can be performed even if such an action is not called upon in daily life. Jouvet explains that REM sleep preserves the correct functioning of such behaviors. It acts as a practice ground in which the execution of these important skills can be maintained and improved.

The "sentinel" theory, developed by Dr. Frederick Snyder, employs quite a different perspective in trying to explain the mystery behind REM sleep . Snyder worked with the findings of Drs. Harmon Ephron and Patricia Carrington. They proposed that REM sleep helped to maintain the continuity of the sleep cycle. They saw this stage of sleep as fulfilling a homeostatic purpose as it regulates the balance between REM and NREM(non REM) sleep. In simpler terms, REM preserves mental poise and readiness that is lacking in the deeper, less active stages of NREM sleep. The mental characteristics of the mind during REM sleep bring it very close to the state of being awake. Ephron and Carrington feel that this feature of REM sleep served to make sure that we do not fall into too deep of a sleep during NREM. Snyder added to the concepts put forth by these earlier studies, creating his "sentinel" theory. He says that these periods of near-wakefulness brought on by REM activity, grant a person an awareness not present during periods of deeper sleep. They could be more easily woken up, thus they are more likely to sense danger. This allows a person to be awake enough to respond to dangerous of threatening stimulus, while letting the person continue their slumber if no such provocation is taking place. This wakefulness during REM offers brief periods of heightened surveillance during which a person is more readily equipped to become aware of a problem. The benefits of this are rather obvious as they serve the purpose of improving protection, while not disrupting the act of sleep. Paradoxically, we dream as a means of waking up, relatively speaking of course. REM acts as a substitute for being awake, as we become more aware of our surroundings, while safely preventing the loss of even a wink of sleep.

This theory is related to the ideas discussed by Peretz Lavie, in his latest book, The Enchanted World of Sleep. Here, he recapitulates Snyder's proposal that, "REM sleep has evolved to allow the organisms periodic scanning of possible signs of danger in the environment."¹⁶ Lavie also advances this theory by stating that REM acts as a gateway between sleep and wakefulness. He uses this to support a claim that REM facilitates the transition from sleep to wakefulness and vice versa. REM allows us to wake up quickly and be fully aware of what is going on. In addition to being an inbuilt intruder alarm, it allows us to more easily drift from wakefulness to deep sleep, and from sleeping to actually being wide awake.

Developmental theories, those that deal with the process of human growth, center around the abundant amount of REM sleep that fetuses are exposed to. It is estimated that a fetus spends as much as eighty percent of its time in REM sleep. Soon after birth this percentage drops drastically, levels off, then begins to steadily decrease. Most developmental theorists agree with the role of REM in adult life as laid out by Snyder. This large amount of REM is due to the developing nature of the infant brain. It is believed that REM in fetuses acts as sensory substitutions to stimulate and aid the development of the brain. The firing of neurons during developmental stages if the brain allows neural pathways to be established, developing important motor and sensory systems. "In these theories, the activation that occurs in REM sleep provides an opportunity for the brain to practice future behavior."¹⁷ This strengthens the connections that babies will need as they come into the world and begin to grow. This synthesized stimulation allows fetuses to prepare for the rigors of life in the real world.

It is along these same conceptual lines that REM theories of learning and memory consolidation have been put forth. Jonathan Winson proposed that, "at the age of two when the hippocampus becomes functional," REM sleep no longer aids in nerve growth, it "takes on its interpretive memory function."¹⁸ The hippocampus is a structure in the brain which plays an integral role in the process of storing memory. Theta rhythm is a signature signal in the hippocampus which has been associated with the memory processing of behavior that is vital to the survival of certain animals. It was found that the brain stem was responsible for the activation of the theta rhythm in the hippocampus during such actions. "A similar process occurs during REM sleep, although there is no incoming information or movement during REM sleep."¹⁹ Winson's studies of hippocampal theta rhythm suggested the correlation between the actions of these animals and the formation of the memories of such actions during REM sleep. These findings were corroborated by the experiments of Dr. Matthew Wilson and Dr. James McNaughton, at the University of Arizona. They also claim that, "during this reorganization and consolidation of memories, the brain creates a more useful representation than what was stored during the actual experience."²⁰ This presents some evidence in support of the theory that REM sleep allows for the improved memory coding of crucial behavior.

Dr. Avi Karni also performed studies in which he explored the possibility that REM sleep played a role in the formation of memory. Karni tested whether REM deprivation had any effects upon the learning of a perceptual skill. Results of this experimentation also hint that REM sleep is somehow involved in processing memory. REM deprived participants showed no improvement in the execution of the task, while those deprived of NREM "showed distinct improvement overnight."²¹

Other theories that have been the subjects of few experimental challenges include the "motivational" theory, maintained by Dr. Gerald Vogel of Emory University. This view holds that REM sleep acts to dampen drive behavior and excitability. This was based upon the increase in excitability and tendency towards drive behaviors, such as sex and eating, that accompanied REM deprivation. The neurotransmitter conservation theory has also not undergone much scrutiny. This stance is based upon the fact that certain neurotransmitters are released constantly during the waking hours. The release of these chemicals seems to shut down completely during REM sleep. The logic of this concept concludes that this suppression of neurotransmitter is linked to the need to conserve such chemicals because of their prolonged use while awake.

These are some of the dominant theories that have been developed and maintained concerning the function of REM sleep. Unfortunately, as in the case of dream research, all efforts to conclusively prove the validity of findings have not led to success. Evidence often supports the above mentioned theories, yet does not offer definitive answers. Research in this field of science continues to grow, and undoubtedly there will be continual progress in the search for the function of both dreams and REM sleep. It is the multi-dimensional layering of several realms of science, and the true uniqueness of our sleeping lives that makes the search for solutions all the more obscure. However, these are the same qualities that peak curiosity and lead more scientists to investigate this mysterious, misunderstood and often overlooked dimenstion of human existence.

Perhaps endeavors in this field are best summed up by the following words of one commentator, "After many careful, experiments, we can now be sure that the main effect of sleep loss is to make us very, very sleepy."²² And on that note, I have one final message for those who are truly interested in conducting your own research, DREAM ON! And maybe you will discover why REM is just dreamy!

Endnotes

1. J. Allan Hobson, The Dreaming Brain. (New York: Basic Books Inc., 1988) "The Functions of REM Sleep and Dreaming"; p286.

2. B. Bower, "Earthquake Shakes Up Nightmare Frequency."Science News vol. 141, May 23, 1992; p342.

3. David Koulack, To Catch A Dream. (Albany: State University of New York Press, 1991) "The Adaptive Functions of Dreams"; p162.

4. Ibid., p162.

5. G. Halliday, "Examination Dreams." Perceptual And Motor Skills vol. 77, October, 1993; p489.

6. David Koulack, To Catch A Dream. (Albany: State University of New York Press, 1991) "The Adaptive Functions of Dreams"; p162.

7.Rosslyn Gaines & Douglass Price-Williams, "Dream Images As A Technique For The Study Of The Creative Processes." Perceptual and Motor Skills vol.70, April, 1990.

8. James Horne, Why We Sleep. (New York: Oxford University Press, 1988) "REM Sleep"; p 256.

9.Sandra Blakeslee, "Clues to the Irrational Nature of Dreams." New York Times July 12, 1994; pC8.

10.J. Allan Hobson, Sleep. (New York: Scientific American Library, 1989) "Dreaming"; p144.

11. Ibid., p144.

12. Staff Writers, "How To Build A Dream." Psychology Today vol. 28, November-December, 1995; p54.

13. James Horne, Why We Sleep. (New York: Oxford University Press, 1988) "REM Sleep"; p 264.

14. Jonathan Winson, "The Meaning Of Dreams." Scientific American vol. 263, November, 1990; p88.

15. James Horne, Why We Sleep. (New York: Oxford University Press, 1988) "REM Sleep"; p 265.

16. Peretz Lavie, The Enchanted World of Sleep. (New Haven:Yale University Press, 1996) "The Eccentricity of REM Sleep"; p148.

17. J. Allan Hobson, Sleep. (New York: Scientific American Library, 1989) "Dreaming"; p194.

18. Jonathan Winson, "The Meaning Of Dreams." Scientific American vol. 263, November, 1990; p96.

19. Ibid., p92.

20. Sandra Blakeslee, "2 Studies Suggest Sleep Is Vital in Consolidating Memories." New York Times July 29, 1994; pA11.

21. Ibid., pA11.

22. Paul Willner, "Functions Of Dreaming: The Emperors New Clothes?" Perspectives in Biology and Medicine vol.34, summer 1991; p596.

Bibliography

Books

1. Cartwright, Rosalind D. A Primer On Sleep And Dreaming. (Phillipines: Addison-Wesley publishing Company Inc., 1978).

2. Hartmann, Earnest, M.D. Sleep and Dreaming. (Boston: Brown, Little and Company, 1970).

3. Hobson, J. Allan. The Dreaming Brain. (New York: Basic Books Inc., 1988).

4. Hobson, J. Allan. Sleep. (New York: Scientific American Library, 1989).

5. Horne, James. Why We Sleep. (New York: Oxford University Press, 1988).

6. Hunt, Harry T. The Multiplicity of Dreams. (New Haven: Yale University Press, 1989).

7. Koulack, David. To Catch A Dream. (Albany: State University of New York Press, 1991)

8. Lavie, Peretz. The Enchanted World of Sleep. (New Haven: Yale University Press, 1996)

9. Strauch, Inge & Barbara Meier. In Search of Dreams. (Albany: State University of New York Press, 1996)

Articles

1. Begley, Sharon. "The Stuff That Dreams Are Made Of." Newsweek vol.14, August 14, 1989; pp41-44.

2. Blakeslee, Sandra. "2 Studies Suggest Sleep Is Vital in Consolidating Memory." New York Times July 29, 1994; pA11.

3. Blakeslee, Sandra. "Clues to the Irrational Nature of Dreams." New York Times July 12, 1994; ppC1, C8.

4. Bower, B. "Recurrent Dreams: Clues to Conflict." Science News vol.129, March 29, 1986; p197.

5. Bower, B. "A Thoughtful Angle on Dreaming." Science News vol.137, June 2, 1990; p348.

6. Bower, B. "Earthquake Shakes Up Nightmare Frequency" Science News vol.141, May 23, 1992; p197.

7. Gaines, Rosslyn & Douglass Price-Williams. "Dream Images As A Technique For The Study Of The Creative Processes." Perceptual and Motor Skills vol.70, April, 1990; pp540-42.

8. Gillis, Anna Maria. "Why Sleep." BioScience vol.46, June 1996; pp391-93.

9. Halliday, G. "Examination Dreams." Perceptual and Motor Skills vol.77, October, 1993; pp489-90.

10. Karni, Avi. "Dependence on REM Sleep of Overnight Imporvement of a Perceptual Skill." Science vol.265, July 29, 1994; pp679-81.

11. Wilner, Paul. "Functions Of Dreaming: The Emperor's New Clothes?" Perspectives in Biology and Medicine vol. 34, Summer, 1991; pp588-98.

12. Wilson, Jonathan. "The Meaning of Dreams." Scientific American vol.263, November, 1990; pp86-96.

13. "How to Build a Dream." Staff writers. Psychology Today vol.28, November-December, 1995; pp47-54.