Dreams Actually Virtual Reality Threat Simulation?

Time Slows Down writes "Psychology Today has an interesting story on a new theory of why we dream. Finnish psychologist Antti Revonsuo believes that dreams are a sort of nighttime theater in which our brains screen realistic scenarios simulating emergency situations and providing an arena for safe training. 'The primary function of negative dreams is rehearsal for similar real events, so that threat recognition and avoidance happens faster and more automatically in comparable real situations,' he says. We have 300 to 1,000 threat dreams per year — one to four per night and just under half are aggressive encounters: physical aggression such as fistfights, and nonphysical aggression such as verbal arguments. Faced with actual life-or-death situations — traffic accidents, terrorist attacks, street assaults — people report entering a mode of calm, rapid response, reacting automatically, almost without thinking. Afterward, they often say the episode felt unreal, as if it were all a dream. 'Dreaming is a sensitive system that tries to pay much attention to the threatening cues in our environment,' Revonsuo says. 'Their function is to protect and prepare us.'"

Yeah

[dreamchaser (49529)]

Last night while I was dreaming of playing poker with Einstein and Hawking and an anthropomorphic Zebra, I stopped and thought "This is really a great simulation of reality!" It got really interesting when the dancing elephants started circling our table. I feel far better prepared for life now.

Re:

[moderatorrater (1095745)]

That's one dream. The summary says that they're looking at 1 to 4 dreams a night, which indicates that the dreams they're talking about are the ones we don't remember.

Re:Yeah

[dreamchaser (49529)]

You need to dream about humor more often, to train you to enjoy it more (or even get it in the first place) in waking life ;)

Re:Yeah

[pixelpusher220 (529617)]

The funny part is some of us *don't* dream. Seriously.

I know that I pretty much stopped dreaming about the time I hit puberty. Vivid dreams as a kid but once I 'grew up' they stopped.

How do I know this you ask? Because during a sleep test for sleep apnea they found out my blood oxygen saturation level was about 80%, below the threshold needed for REM sleep. So from about 12-14 to 26, I couldn't dream. Just not enough oxygen to do it.

There were the occasional odd dreams when a sleeping position allowed better than normal oxygen levels, but mostly I just didn't.

Even today, after the surgery, my dreams are wildly mild stuff. Mostly just replaying some experience of the recent days.

It did sort of explain why HS was mostly just a fog for me though...going without restful sleep for multiple years will do that ;-)

Re:Yeah

[Nykon (304003)]

"I know that I pretty much stopped dreaming about the time I hit puberty."

That's a shame. The good dreams don't start until puberty ;-)

Re:

[syousef (465911)]

How long ago did you have the surgery? How painful was it? The failure/recurrence rate after surgery for most sleep apnea is abysmal unfortunately so make sure you schedule another sleep test a year or so after surgery if you haven't already.

I was diagnosed with sleep apnea about 5-6 years ago now. I'm 32. CPAP machines are horrible but they're better than the alternative for me. (3 nights without CPAP and I'm a headachy zombie with a very sore throat, plus my wife gets no sleep. I don't doubt I'd have lost

Re:Yeah

[rkanodia (211354)]

If you don't think you do, go to one of those sleep study centers and book yourself for the night.

Way to go, Captain Reading Comprehension. The GP did exactly that.

Re:

[morcego (260031)]

The sleep test for apnea is very different than a dream related test.

I know he didn't state he was unable to ever reach REM state, but it seems you chose to interpret it that way. Also, you will see he stated he did have "occasional odd dreams".

Dream doesn't happen exclusively during REM. Yes, deep, vivid dreaming happens during REM, but that is different. A dream related study, using an EEG, will show altered brainwave patterns during 3 of the 4 sleeping states. Btw, it is very rare for people to remember

Re:I call bullpatootie

[Rei (128717)]

Well, at least I'll be prepared when a witch tries to shepard soul crystals down a river with the hopes of winning favor from a god that, unbeknownst to her, is the father of the land's emperor and has already favored him instead, and I have to teleport into the emperor's aerial flagship to gather information. ;)

Re:I call bullpatootie

[BorgCopyeditor (590345)]

*leans back and holds pen and pad at the ready*

Tell me about your mother.

Re:

[cayenne8 (626475)]

Great....just great.

Now,tonight, I'm gonna be having nightmares of a Slashdot nature....repeating meme's turning into spiraling thoughts, and endless encounters with goatse pics, and alt-tab won't work any longer...EEEEEEEEEEEEEEEEEEEEEEEEEEEEEE!!!!!!!!!!

Re:Yeah

[badasscat (563442)]

That's one dream. The summary says that they're looking at 1 to 4 dreams a night, which indicates that the dreams they're talking about are the ones we don't remember.

That doesn't do anything to explain away the implied criticism. We presumably have dozens of dreams per night that we don't remember, the vast majority of which are neither realistic nor "threat dreams". So what's the purpose of those?

I don't think there's a scientist anywhere that thinks some dreams serve one purpose and other dreams serve another. Dreaming in general probably serves more than one purpose simultaneously, but every dream serves those same purposes... whether it's defragmenting memories, or cataloging fantasies, or whatever. REM sleep is REM sleep; there are no different "categories" of REM sleep. And clearly, most of our dreams have nothing whatsoever to do with preparing us for threats. Simply using anecdotal quotes about people saying "it was like a dream!" when they respond to a real life threat situation is hardly proof of anything.

This is one of those cases where a single "false" result precludes a "true" result from the rest of the experiment. And we've all got plenty of "false" results every night.

Re:Yeah

[jpfed (1095443)]

This is one of those cases where a single "false" result precludes a "true" result from the rest of the experiment.

I propose that the purpose of our ears is to help us hear. But some people are born congenitally deaf. These "false" results don't render my idea incorrect- and my suspicion is that this is because "purpose" means something different in an evolutionary context than it does when we speak of other intelligent agents that have purposes.

So what sense does it make to say that a behavior or phenomenon produced by evolution has a "purpose"? I think "the purpose of X is Y" is verbal shorthand for saying "Y is an effect of X, which accrues some net reproductive benefit". In that interpretation, a single "false" result is not sufficient. Some dreams don't do their "job". But as long as enough of them do, and you live incrementally longer and have more long-lived children as a result, then the dreams will have fulfilled their evolutionary "purpose".

That's not to say that this work has some outstanding merit. Under this interpretation, to claim that something has a particular evolutionary purpose is a pretty weak statement.

Re:

[steelfood (895457)]

Your analogy doesn't work. People who are born deaf are born with a missing part of the ear or the brain that processes auditory information. People who become deaf usually are deaf for a reason that we know about. In the latter case, action and result are directly observable.

Nobody is genetically or otherwise hardwired to dream everything bu tthis one type of dream. And there's nothing to show that "threat simulation" is a near guaranteed result of a particular past event. Dreams vary per night. The same p

Re:

[jpfed (1095443)]

Your analogy doesn't work. People who are born deaf are born with a missing part of the ear or the brain that processes auditory information. People who become deaf usually are deaf for a reason that we know about. In the latter case, action and result are directly observable.

Point taken. But there are certainly cases where the "purposes" of evolution are not 100% reliable. For example, if you want to believe some evolutionary psychologists, you'd think that men do silly stunts to impress women. They don't impress every woman, but they impress enough that they get to spread their seed around, and that's good enough.

Maybe, just maybe, these rats were tired too.

They gave the rats amphetamines specifically to counteract the tiredness. Whether or not that manipulation actually does what they're hoping, I couldn't say- bu

Re:

[Brad Eleven (165911)]

Memory is associative. This implies that remembering a dream while conscious depends on strong associations held by the conscious mind. That's the random part: the dream one happens to remember is the one that has more in common with one's conscious personality. If you think you're not good at fighting, you'll probably remember the dreams where you didn't do so well in a fight. Conversely, when an actual fight situation comes up, you're more likely to do poorly if your conscious mind is engaged. Compare and

Re:

[Zenaku (821866)]

That's odd. My dreams are distinctly unrealistic, but FEEL perfectly natural when I'm having them. I routinely fly, teleport, shape-shift, and use telekinesis, and in the dream it seems to me as if I have always been able to do those things and there is nothing unusual about it. It's not even like a super hero fantasy. . . it just feels like everyday life, and in the dream-state, it doesn't even occur to me that those things are impossible. In addition, I frequently dream that I'm hanging out with a fri

Re:Yeah

[morgan_greywolf (835522)]

Last night while I was dreaming of playing poker with Einstein and Hawking and an anthropomorphic Zebra, I stopped and thought "This is really a great simulation of reality!" It got really interesting when the dancing elephants started circling our table. I feel far better prepared for life now

Hmm.. Well, I'm not really a dream interpretation expert, but I play one on the Net. Anyway, many dreams are just the mind's way of working out problems -- or calling attention to problems -- that are currently occurring in our lives. Most of what occurs in people's dreams is more of a metaphor for something else.

Take, for example, the oft-cited 'I dreamt that I showed up to work/school/whatever naked/wearing only underwear.' Showing up to work naked isn't actually the real problem the brain is trying work out. The real problem is that the person is a afraid of being unprepared or being caught in an embarassing situation. They are usually insecure about something or other when they have dreams like this. This is the brain trying say "Hey, you! You're insecure about this or that, what are you doing to fix that?"

Of course, the imagery of dreams isn't always that universal. In your case, what do Einstein and Hawking represent for you? What about zebras? What does playing poker mean to you? Do you bluff a lot in poker? Or do you play on the merits of your cards? If you're a physicist, and just making guesses here about the zebra, I'd say that you that see Einstein and Hawking as a black-and-white dichotomy that needs to somehow be resolved. Maybe you think one of Hawking's theories and another of Einstein's are in deep conflict and maybe you see yourself as trying to resolve that. Of course, if you're not a physicist, the dream could mean something else entirely.

Re:

[inviolet (797804)]

Take, for example, the oft-cited 'I dreamt that I showed up to work/school/whatever naked/wearing only underwear.' Showing up to work naked isn't actually the real problem the brain is trying work out. The real problem is that the person is a afraid of being unprepared or being caught in an embarassing situation. They are usually insecure about something or other when they have dreams like this. This is the brain trying say "Hey, you! You're insecure about this or that, what are you doing to fix that?"

Or m

Re:

[JWW (79176)]

Of course, the imagery of dreams isn't always that universal. In your case, what do Einstein and Hawking represent for you? What about zebras? What does playing poker mean to you? Do you bluff a lot in poker? Or do you play on the merits of your cards? If you're a physicist, and just making guesses here about the zebra, I'd say that you that see Einstein and Hawking as a black-and-white dichotomy that needs to somehow be resolved. Maybe you think one of Hawking's theories and another of Einstein's are in de

NUDE

[chowhound (136628)]

Apparently my brain is exhaustively preparing me for the possibility that I'll drive to work naked.

Re:

[eebra82 (907996)]

Are you sure it's not just preparing you for the possibility of doing it again? Some dreams are read from past events you've long forgotten about.

Re:NUDE

[moderatorrater (1095745)]

Doesn't that make sense to a certain extent though? While you'll (hopefully) never face that exact situation, dealing with embarrassment is a very real danger, and clothing tends to be very easy to embarrass yourself with. Ripping your pants, wearing your shirt backwards, your zipper being down, etc, are all things that could happen basically any day of the week and would be embarrassing. Not as embarrassing as driving to work naked, but pretty embarrassing nonetheless.

Re:NUDE

[eclectic4 (665330)]

Apparently my brain is exhaustively preparing me for the possibility of having sex with Jessica Alba. All I can say, is that I'm very, very prepared...

Negative? Threat?

[SanityInAnarchy (655584)]

So you're saying that was a negative dream to you? And that your brain is preparing you for the threat of sex with Jessica Alba?

Dreamt of that before

[Marcion (876801)]

> What struck him the most was how lifelike they were. "I would say to myself, in my dream, 'Oh shit! I've dreamt of this before, but now this is really happening!' " he recalls

I actually get that. And I thought I was like Isaac Mendez, now it just my brain running simulations. the fact my brain gets it rights shows how dull and predicable my life must be....

That explains it

[MrHanky (141717)]

All those dreams I had of being chased and then not being able to run, losing all the power of my usually very strong and quick legs. It's all there to prepare me for giving up in case a real situation should arise. Thank you, science of psychology.

Re:That explains it

[provigilman (1044114)]

Or perhaps because you feel that your legs are strong and quick, your brain is trying to trying to train you on what you could do if you couldn't use your legs. What if you twisted your ankle while running? Then you might have to turn and face your attacker, rather than that running.

That's what the TFA was getting at. It's not so much that your brain is like "This is the most likely scenario", but rather that it's decided that this is a "feasible" scenario that you should be prepared for.

Re:

[Scrameustache (459504)]

All those dreams I had of being chased and then not being able to run, losing all the power of my usually very strong and quick legs.

That's your subconscious saying "yeah? Well what if our legs DON'T work, what'll you do then, smarty pants?"

Interesting

[jellomizer (103300)]

It makes since, and could explain other things as well. Such as why adults are more apt to not have as many horrible nightmares. They still have the negative situations but they seem to handle the situations better, so they are less scary after a while because they know what to do. Evolutionary reason for dreaming, it seems like a silly thing to evolve a period of a beings life where they body goes into paralysis just so they don't kill themselves from acting lucid imagery, the fact the dreams gave us a survival advantage would explain the tradeoff of the paralysis during the night.
This seems a good theory. It should be investaged further.

Overbearing

[Fantastic Lad (198284)]

Evolutionary reason for dreaming, it seems like a silly thing to evolve a period of a beings life where they body goes into paralysis just so they don't kill themselves from acting lucid imagery, the fact the dreams gave us a survival advantage would explain the tradeoff of the paralysis during the night.

This assumes that all elements of life in this reality resolve down to questions of evolutionary theory, which I think is false. --I tend to think that we are not living in a closed system; that there are a LOT of outside forces at work which dramatically affect the human species and which have little to do with natural selection, --that and the rules which govern our reality are infinitely more complex than is currently understood. When people are positing theories based on such enormously limited understandings, then the best they can hope for is to be hopelessly wrong with a chance of nudging themselves in the right direction; IF, that is, they are willing to kill their sacred cows, (or at least allow them to starve to death). As such, this is a stab in the dark at best, and while there is certainly some substance to the idea of solving problems during dream time, I very much doubt these researchers have the chops to know what the heck they're actually playing with. I wonder how they would account for such simple items as lucid dreaming and many of the other odd dream experiences noted by every second person who posted in this thread?

I really don't mean to hammer on you personally, and indeed I hope you will forgive me if it appears I am doing so, but it's just that I find this kind of science quite overbearing in its general conceit and intent. --It's another attempt to shave another strip of humanity from the human being; to reduce us all to less than what we are through the application of Socratic nonsense logic dressed up in lab coats. Ugh. This can be really limiting in that belief and existential reality are linked at the hip. (Believe you are less, and that is what you will become.) The general tone of this kind of work reminds me of reading old science texts which spoke with authority upon subjects which it later turned out they were hopelessly wrong concerning.

The dream realm is one of the few areas which reductionist science hasn't been able to taint. It allows personal freedom even within deliberately oppressive environments. It is just like a fascist regime as ours (where the prisoners are also the proud prison builders and guards), to attempt to convince people that their own dreams are worthless without state approval. The hell with that.

-FL

Re:Overbearing

[spun (1352)]

It sounds as if you think of human beings a fundamentally mysterious, outside the bounds of science. How can science possibly strip us of our humanity? All it does is provide an explanation of what humanity actually means. If that actuality is not what you romanticized humanity to be, I can see how that might be disillusioning, but science can't strip anything of something it actually has. All it can strip away is what people falsely think it has.

Reductionist science? What is that? How is this an attempt to convince people their dreams have no worth? What does state approval have to do with anything? Are you really that anti-science?

Do you live within an oppressive environment? I mean, North Korea, say? Do you know what people's dreams are like there? Maybe they have nightmares all the time.

Not that I'm saying that this hypothesis about dreams has any merit. But any kind of mystical or metaphysical hypothesis for dreams has even less merit.

Re:Overbearing

[jellomizer (103300)]

The flaw in your logic is the fact that other animals other then Humans dream, and the process of dreaming puts an animal in physical danger, In a state where there is minimal control to the bodily movement, as well as waking up and potentional short term disoreatation. All this could cause animals to who dream to get eaten by non-dreaming preditors. Giving them a disadvantage over their preditors. Evolutionary science can explain why this exists, not nessarily why we use it the way we normally like to do. Our thumbs were evolved to help us to climb, we now use them to create. Evolution Gave us our thumbs to survive, we as humans use our thumbs to move to the next step. Evolution gave us dreams as a survival mechnism, we use dreaming to inspire and move us to the next step.
Its not an attempt to strip humanity it is an attempt to understand it. Dont let huberious get in the way we are Animals many of our actions as a people and a culture has reasons.

Re:

[steelfood (895457)]

To say that dreams are a virtual reality, or a simulation of reality within our minds, is a good way of describing dreams.

To attribute a reason to this phenomenon based on shaky, selective anecdotal evidence sounds suspiciously like supersitition.

I've had such dreams before. I've had dreams of fighting, of killing, of being in mortal danger, and of being wounded. Sometimes, I wake up before the action begins, sometimes in the middle just as things are about to get good, sometimes I can force myself to conti

interesting...

[Ralph Spoilsport (673134)]

It's like nature's version of QA.

OK - let's do some load testing. HA! See? The test server fried. Fix that - so now it passes to other test servers. Set up? OK - run the test. See? Load OK. Good. Now config the prod servers like that, and we'll be good. Next? copy paste evil Evil EVIL hacker script into data entry on test server. Did it fail? Yes? Good. Prod server's fine then.

OK - you're dreaming that everyone is chasing you (load testing), so you pass the magic baton to someone else and the crowd runs past you. You are in a horrible argument with someone (hacker script) and you smash their brains in and feel happy about it.

Dreams as mental QA scripts. I like that! It makes a kind of "sense", and demonstrates the necessity of not only dreaming BUT PAYING FOR GOOD QA SO YOU DON'T PUT OUT A SHIT PRODUCT. Hopefully that will be heard in Redmond - but they never sleep, so they never dream...

RS

Nightmares

[rice_burners_suck (243660)]

Maybe that's why I keep having that nightmare about turning on my Mac one day only to find it's suddenly running Vista!

A fine theory on the imaginations of rats

[ooutland (146624)]

The article covers *rats*, and it explains what happens to a small, limited rat brain when it can't dream. And yes, it explains *some* human dreaming. But, what is going on in my human head when I dream of dead loved ones? What does that prepare me for? Are my dreams of being naked in public just training ground to remind me to get dressed every morning? Or do they reflect buried insecurities or anxieties? Maybe dreams started as a way for our primitive, simple brains to train themselves to survive, but their reason for being today, in our more advanced brains, is still a mystery.

Sweet Dreams are Made of This

[CristalShandaLear (762536)]

The other night, I dreamed that I misjudged a car exit and drove through a rail, over an embankment and into a river. As the river got closer, the water turned the color and consistency of Google Earth water when you get too close and just as I submerged, my car bounced back out again and onto the road (just like Neo in the jump program). I was soaking wet, but otherwise unharmed. I don't think my brain was trying to prepare me for this type of emergency. I think it's more likely that I've seen the Matrix one time too many, that I just started a new gig where part of my job is to find aerial views of properties on Google Earth and that I'm from Ohio where 6 people from my home state died in an accident where a bus went over an overpass? And I kept watching Bourne 2 before Bourne 3 came out, a movie where a car dives into water. I think dreams are made of the total of our experiences. Our "weirder" dreams are our experiences combined with our imagination's flights of fancy, our experiences and our more subtle observations - things that may not register when we see them, but are still lodged in our memories - like people only remembering a license plate number through hypnosis.

Evolving Reality with Age

[Sponge Bath (413667)]

When I was a young child I had disturbing nightmares about scary monsters and falling.
Recently I had a dream about someone dinging my fender in traffic.

I guess that's the evolution of my reality:
From Earth shaking terror to bored annoyance.

Bothersome image

[stewbacca (1033764)]

Am I the only one bothered by the high occurence of slashdotters dreaming about themselves naked? Ewwww.

Nonsense!

[eno2001 (527078)]

The aborigines of Australia have got it right. Dreams are reality. Just in a different universe. Once I got that straight, it really explained why all of my dreams are so whacked and have nothing to do with real life. When you dream, you're experiencing life in a different parallel world. Simple as that. (cough)

Modern dreams?

[twifosp (532320)]

Interesting concept, but wouldn't modern dreams have adapted to modern problems by now? I also thought (perhaps incorrectly) that the flight or fight response was mostly subconscious. So would "dream training" even help you in those situations?

I would personally think dreams are more hormonal than that. A while back I began taking a vitamin supplement of zinc and magnesium (ZMA). A side effect of this vitamin combo is vivid dreaming. You notice right away that your dreams are more lucid, and you remember more of them. Right away I noticed that my dreams were very violent or sexually oriented. Now this vitamin supplement increases testosterone production as well (when combined with exercise). So I'm not quite sure if my violent/sexual dreams increased as a result of testosterone production, or that I was already having these dreams, and my memory/frequency of them was improved. I happen to think it is the latter because you notice the dreams on the first night of taking the vitamins.

Either way, my dreams include fights, wars, sexual encounters, robberies, and all sorts of crazy behavior that just simply doesn't apply to my life. If dreams were a virtual reality training program, I wonder why they haven't adapted to train me for my real world problems that need solving. Not robbing a bank Heat style (a rather lucid dream I had the other night).

I suppose the socially embarrassing dreams such as arriving to work naked might be a counter-point, but I just don't buy it.

On that related note if anyone is interested in lucid dreaming, I highly recommend it. Google around for some quick guides. It's not very hard and requires very small amounts of simple self-hypnosis to start. Simply thinking of the question during your waking hours over and over again "Am I awake or am I dreaming" was enough for me to start asking myself that question while I was dreaming after a week. Once this question appears in your dreams and you recognize it enough to answer "dreaming", you can have lots of fun with lucid dreaming.

I highly recommend the vitamin ZMA (Zinc Magnesium Aspartame) combined with valerian root* 30 minutes before bed. Also keep a dream log for maximum enjoyment. Lucid dreaming can be a lot of fun. Trying to get to know your own subconscious is a real challenge and it never gets boring.

*Valerian root has very very pungent odor that can make your breath smell for hours after you take it. It sits in your stomach and seems to work its way up, no matter how clean your mouth is. It also has the reverse effect of pineapple juice, if you catch my drift. Thankfully ZMA on it's own is enough to enhance your dreams. Valerian root does provide that extra kick, so it's good to try now and again. Just do your SO a break and only use it sparingly.

Unfalsifiable

[exp(pi*sqrt(163)) (613870)]

Read the part of the article starting:

But not all our dreams contain threats. That's not surprising, says Revonuso. There's no reason a biological system has to express its function at all times...

It's a clever move. It makes the theory immune to falsification. Of course that also makes this theory pseudo-science, but you hope people won't notice that. In fact the analogy with sperm is flawed. The fact that there are many sperm that fail to fertilize an egg does stand in need of explanation. See Matt Ridley's book "The Red Queen" for some discussion of this. Similarly non-threat dreams stand in need of explanation.

Personal experience...

[Phanatic1a (413374)]

One fairly common dream that people in the self-defense community have is the one where you come under sudden attack and your gun malfunctions, or is out of ammunition, or for whatever reason you can't fire it at your dream-attacker.

I didn't have this dream *until* I started training with a handgun for self-defense purposes. I grew up hunting, with rifles and shotguns, and didn't have this dream. Not until I incorporated the self-defense aspects into my identity. Then my brain started to throw that dream at me.

So, yeah, I can buy this idea.

Re:

[davidbrit2 (775091)]

Full-contact theological debate, evidently.

Re:You ever have that dream...

[truthsearch (249536)]

So what about that dream where I'm naked at work and Jesus is fighting Nietzsche in pudding? What the hell is THAT training me for?

Coming out of the closet?

Re:What Dreams May Come?

[Cro Magnon (467622)]

You KNOW you've been wasting too much time on /. when your dreams get duped!

Re:

[bcattwoo (737354)]

My brother had a recurring dream as a kid. He was chased over and under his bed by an octopus. What kind of threat was he preparing for?

Rising sea levels as a result of global warming. Duh.

Re:

[Matteo522 (996602)]

"Neurons that fire together, wire together."

Whether or not you remember them, the dreams still caused a physical reaction in your brain. So if you spent your night dreaming about Guitar Hero, whether or not you remember the dream, you'll find yourself playing better the next day because you still practiced it by playing through the simulation in your head all night. Your brain believed it had a real experience because it sent the real signals to the various parts of your brain/body (the brain stem block

no wonder psychologists don't get respect

[Quadraginta (902985)]

And that is what passes for proof of a theory? No wonder psychology is the poor stepchild of the true sciences. I mean, I can think of about three other explanations off the top of my head that also explain why the mouse was less aware of danger after being prevented from REM sleep, viz.:

(1) It was bloody tired after being woken up all the time the night before.

(2) REM sleep is just a way for the short-term memory banks to do a dump and clean out all the crap that's accumulated during the day, useless sensory data. Since the poor mouse was prevented from doing the reformat on /dev/swap, it didn't work so well the next day, and the mouse's short-term sensory memory of what was in its environment was degraded. You might as well have given it a few hard knocks on the head.

(3) REM sleep is just a weird, accidental by-product of some necessary biochemical house-cleaning that goes on at night. Some metabolic side-product chemical gets produced, and it jiggles the imagination handle randomly in the brain while we're asleep. The resulting images don't mean a damn thing, any more than the flashes in the eye when you rub your tired eyes. But because the mouse was prevented from doing the biochemical house-cleaning, whatever it is, he didn't function as well the next day. That is, the mouse's poor performance had nothing to do with the prevention of its dreams, but rather with the prevention of whatever else was going on that independently caused the dreams.

None of these theories is disproved by the data you mention, so they're just as good as the psychology professor's theory.

One of the unfortunate ways in which even quite educated people misunderstand empirical science is that they don't fully appreciate that finding an explanation for the data isn't at all the same as finding the explanation. There are usually bazillions of theories that match the data: the trick is designing an experiment that, along with common sense and experience, can rule all but one of them out. This experiment with the mouse certainly doesn't qualify.