Rats Dream About the Places They Want to Explore

By K. N. Smith | June 26, 2015 12:02 pm

rat sleeping

Rats, like humans, have dreams about the future.

When they see a treat they can’t reach, rats’ later dreams depict them walking toward it, researchers have found. The discovery may one day provide some insight into what happens in the human mind during sleep.

Maps in the Brain

Scientists already knew that after a rat has explored an area, certain neurons in the hippocampus called “place cells” replay those patterns while the rat sleeps.

“Place cells” in both rats and humans help us store memories about location and form mental maps. When you’re in one spot, a set of place cells fires; when you move to another spot, a different set of place cells fire to mark the new location. If scientists can record the activity of specific brain cells, then, they can spy on how the mind maps new places. So far, that kind of recording requires implanting tiny electrodes on very thin wires into the brain, which can’t be done with human subjects for ethical reasons, but it’s possible with rats.

But can rats mentally map a new place before they’ve explored it? Can they, in some sense, “imagine”? That was what researchers set out to study.

Dreaming of the Future

First, researchers let rats explore a T-shaped track. The rats could run along the center of the T, but the arms were blocked by clear barriers. While the rats watched, researchers put food at the end of one arm. The rats could see the food and the route to it, but they couldn’t get there.

Then, when the rats were curled up in their cages afterwards, scientists measured their neuron firing. Their brain activity seemed to show them imagining a route through a place they hadn’t explored before. To confirm this, researchers then put the rats back into the maze, but this time without the barriers. As they explored the arm where they had previously seen the food, the rats’ place cells fired in the same pattern as they had during sleep.

This mental mapping process made up about 8 percent of the rats’ brain activity during sleep. That may not sound like much, but neuroscientist Hugo Spiers, a co-author on the study published in eLife, says it’s a significant amount of activity for the brain to devote to a single task during rest.

Like Rodents, Like People?

The rats’ activity may shed some light on what goes on in the human mind during sleep. Sleeping does seem to improve human performance on memory tasks – a finding which has been used to argue against all-night study sessions. And desire is also a crucial part of that process for people. “People are much better at doing the stuff that they’ll make more money on after they’ve slept,” said Spiers. “Something about sleep is using that desire information: that you do want to do better.”

The rat experiment makes it easy to see the possible evolutionary benefits of dreaming, or something like it, although it’s not clear yet whether mapping future routes to food during sleep actually helps the rats navigate later. That, says Spiers, is material for a future experiment.

The Stuff of Dreams

Researchers aren’t sure yet whether this mental mapping is related to dreams or a different mental process. “People have talked in the past about these kind of replay and pre-play events as possibly being the substrates of dreams, but you can’t ask rats what they’re thinking or dreaming,” said Spiers.

But he added, “There is that really interesting sense that we’re getting at the stuff of dreams, the stuff that goes on when you’re sleeping.”


Image by Vitalii Tiagunov / Shutterstock

CATEGORIZED UNDER: Living World, Mind & Brain, top posts
MORE ABOUT: animals
  • zlop


    • Mongoose

      People do the same thing.

      • zlop

        However, I have not seen a Dog sleepwalk.

        • Mongoose

          That’s a really interesting possibility.

          • zlop

            I have seen a dog trying to sleep-bark.

          • Mongoose

            Me too! Kind of like “Whoof, puff, whoof, squeak.” Reminds me of my husband. Or maybe it is my husband.

          • zlop

            Was your husband dreaming of you, or of another woman?

          • Mongoose

            I asked him. What do you think that super-smart man said?

          • zlop

            He dreamed of you, with a different hair-do?

          • Mongoose


  • Stella4578

    If you could use extra income of about 50-300 bucks on daily basis for doing simple work from comfort of your house for few hrs every day then try this…

  • bgrnathan


    Babu G. Ranganathan
    (B.A. Bible/Biology)

    Just because something exists in nature doesn’t mean it was invented or made by Nature. If all the chemicals necessary to make a cell were left to themselves, “Mother Nature” would have no ability to organize them into a cell. It requires an already existing cell (with a directing genetic code and biological machinery) to bring about another cell. The cell exists and reproduces in nature but Nature didn’t invent or design it! Nature didn’t originate the cell or any form of life. An intelligent power outside of nature had to be responsible.

    Stanley Miller, in his famous experiment in 1953, showed that individual amino acids (the building blocks of life) could come into existence by chance. But, it’s not enough just to have amino acids. The various amino acids that make-up life must link together in a precise sequence, just like the letters in a sentence, to form functioning protein molecules. If they’re not in the right sequence the protein molecules won’t work. It has never been shown that various amino acids can bind together into a sequence by chance to form protein molecules.

    Also, what many don’t realize is that Miller had a laboratory apparatus that shielded and protected the individual amino acids the moment they were formed, otherwise the amino acids would have quickly disintegrated and been destroyed in the mix of random energy and forces involved in Miller’s experiment. A partially evolved cell (an oxymoron) would quickly disintegrate in the open environment, not wait millions of years for chance to make it complete and then become living.

    Miller’s experiment produced equally both left-handed and right-handed amino acids, but all living things strictly require only left-handed amino acids to be in the right sequence. If a right-handed amino acid gets into the chain the protein won’t work. DNA and RNA, comprising the genetic code, require strictly only right-handed nucleic acids to be in an exact sequence.

    The probability of just a single average protein size molecule arising by chance is 10 to the 65th power. Mathematicians have said any event in the universe with odds of 10 to 50th power or greater is impossible! Even the simplest cell is made up of many millions of various protein molecules. The late great British scientist Sir Frederick Hoyle calculated that the the odds of the simplest cell coming into existence by chance is 10 to the 40,000th power! How large is this? Consider that the total number of atoms in our universe is 10 to the 82 power.

    The odds of even the simplest DNA code originating by chance is similar to that of a monkey producing a dictionary (with all the letters, words, and punctuation in the right sequence) by randomly pressing the keys on a computer keyboard or typewriter.

    Natural laws can explain how an airplane or living cell works, but it’s irrational to believe that mere undirected natural laws can bring about the origin of an airplane or a cell. Once you have a complete and living cell then the genetic program and biological machinery exist to direct the formation of more cells, but how could the cell have originated naturally when no directing code and mechanisms existed in nature? All of the founders of modern science believed in God. Read my Internet article: HOW FORENSIC SCIENCE REFUTES ATHEISM

    Only evolution within “kinds” is genetically possible (i.e. varieties of dogs, cats, etc.), but not evolution across “kinds” (i.e. from sea sponge to human). How did species survive if their vital tissues, organs, reproductive systems were still evolving? Survival of the fittest would actually have prevented evolution across kinds! Read my Internet article: WAR AMONG EVOLUTIONISTS! (2nd Edition).

    Natural selection doesn’t produce biological traits or variations. It can only “select” from biological variations that are possible and which have survival value. For example, if a variation occurs (i.e. change in skin color) that helps an animal to survive, that survival is called being “selected.” The real issue is what biological variations are possible, not natural selection.

    Modern evolutionists believe and hope that over, supposedly, millions of years, random genetic mutations in the genes caused by environmental radiation will generate entirely new genes for natural selection to use. This is total blind and irrational faith. It’s much like believing that randomly changing the sequence of letters in a romance novel, over millions of years, will turn it into a book on astronomy! That’s the kind of blind faith macro-evolutionists have.

    Mutations are accidents in the genetic code, are mostly harmful, and have no capability of producing greater complexity in the code. Even if a good accident occurred, for every good one there would be hundreds of harmful ones with the net result, over time, being harmful, even lethal, to the species. At best, mutations only produce further variations within a natural species. Even so, mutations are not the best explanation for variations within a natural species.

    Since it isn’t rational to believe that genetic information, like any other form of information, can arise by chance, then it is totally rational to believe that God (the Supreme Genetic Engineer), from the beginning, placed within all natural species the recessive and dominant genes to produce the varieties we find within natural species.

    If life on earth had really existed for millions of years, all species would have become extinct by now due to the colossal number of accumulated mutations over time (please read the author’s popular Internet article, ARE FOSSILS REALLY MILLIONS OF YEARS OLD?).

    What about genetic and biological similarities between species? Genetic information, like other forms of information, cannot happen by chance, so it is more logical to believe that genetic and biological similarities between all forms of life are due to a common Designer who designed similar functions for similar purposes. It doesn’t mean all forms of life are biologically related! Only genetic similarities within a natural species proves relationship because it’s only within a natural species that members can interbreed and reproduce.

    “JUNK” DNA ISN’T JUNK. It’s we who were ignorant of its usefulness. Recent scientific research published in scientific journals such as Nature and RNA has revealed that the “non-coding” segments of DNA are essential in regulating gene expression (i.e. when, where, and how genes are expressed, so they’re not “junk”).

    Even more recent scientific evidence shows that they do code for proteins, after all, and that we need to readjust our thinking of how the cell reads the genetic code (Read “Human Proteome More Complex Than Previously Thought,” Internet article by Dr. Jeffrey Tomkins). Recent research also shows that repetitive (or so-called “useless”) structures in DNA are vital in forming the chromosome matrix, which, in turn, enables chromosomes to be functional and operative.

    Read my popular Internet articles, HOW DID MY DNA MAKE ME? and HOW FORENSIC SCIENCE REFUTES ATHEISM

    Visit my newest Internet site: THE SCIENCE SUPPORTING CREATION

    Babu G. Ranganathan*
    (B.A. theology/biology)


    * I have had the privilege of being recognized in the 24th edition of Marquis “Who’s Who In The East” for my writings on religion and science, and I have given successful lectures (with question and answer time afterwards) defending creation from science before evolutionist science faculty and students at various colleges and universities.

    • Rattbag

      This is irrelevant and inaccurate.

    • Cat Casidy

      In regards to your asterisk, do you have transcript or vid? Audio? Color me interested.

    • Cat Casidy

      I’m just gonna go ahead and assume this is what you are referring to.

    • Grady Wymer


      I posit that energy is the form of organization that is left out of the argument. Gravity is the driver behind the nuclear fission at our star. With regards to life, nothing lives without that source of energy. However in the end, entropy wins. The end. Cold space will become so random and diffuse, that gravity will not be able to regenerate our universe.

      • zlop

        “However in the end, entropy wins. The end. Cold space will become so
        random and diffuse, that gravity will not be able to regenerate our universe.”?

        Now way. Universe has a tendency towards development,
        not Death by Entropy. In a force field, what meaning Entropy?
        (See Modified Feynman Ratchet)

    • BillPosters

      For God’s sake, use your brain, think objectively, read more, grow up and don’t be scared of being alone in the universe. Your description of “Mother Nature” as “disorganized” without help from a higher power, is ridiculous when you consider the power of mother nature’s self-driven processes. You’re forgetting heat, light and pressure. It’s not just chemistry, it’s all the other forces including time. Millions of years of pulsating heat, light, pressure and the right chemistry… is enough to kick start life. Deal with it. Your hope for something more is innocent enough, like a child believing in Santa Claus, but keep it inside your church, it doesn’t belong here.

  • bgrnathan


    by Babu G. Ranganathan

    (B.A. Bible/Biology)

    The Bible teaches that animals have a soul. Animals do not have a soul as advanced as humans, but they do have a soul. The same Hebrew word for “soul” used in the Old Testament in regard to man’s creation is also used for animals, but the translators of the Bible did not want to translate it as “soul” for animals because it offended them. The word “soul” in the Bible has to do with conscious life, as opposed to bios, or simply plant and vegetative life.

    In the Old Testament the Hebrew word for “soul” (“nephesh”) is used for both animal and man. For example, Genesis 1:21 says: “And God created great whales, and every living creature that moveth …” The words “living creature” are from the Hebrew words “nephesh chaiyah”. The same Hebrew words are used in Genesis 2:7 where we read concerning the creation of man that after God had created man from the dust of the earth He then breathed into man the breath of life and man became a “living soul” (“nephesh chaiyah”). The definition of “soul” actually varies according to the context of Scripture. The basic meaning of “soul” in Scripture refers to the mind or conscious nature in animals and man, possessing characteristics of thought, emotion, and will. Animals are not totally controlled by instinct. Animals can learn, love, and show and receive affection. They can get depressed. Witness some pets at their owners’ funerals. Yes, animals can think and even figure things out. Even if animals are used for food, they should be treated and killed as humanely as possible. They have a soul. Cruelty and torture towards animals is sin.

    The Bible teaches us to have sensitivity to animals’ feelings. We read in Deuteronomy 14:21 “Do not cook a young goat in its mother’s milk” (NIV). Deuteronomy 22:6 says, “If you come across a bird’s nest beside the road, either in a tree or on the ground, and the mother is sitting on the young or on the eggs, do not take the mother with the young” (NIV).

    The Bible teaches in Genesis 1:30 that in the beginning all animals, birds, and insects subsisted on a vegetarian diet. God created a perfect world in the beginning. Suffering and death entered into the world only after man’s sin. Man’s sin not only affected mankind but everything under man’s dominion.

    The soul may very well be physical but yet distinct from the rest of the body. Even if the soul is not physical it wouldn’t necessarily mean that soul is immortal. Immortality must be given by God Who alone is the ultimate Source of all life. It is very humbling to realize that we humans were created as mortal as the animals. As for humans, only those who have put their faith in Jesus Christ as Lord and Savior will ultimately have immortality of soul and body on Resurrection Day.

    Just because man is created in the image of God does not mean that man must possess every attribute God possess or that God can communicate to man. Man was not created immortal. That’s why there was a Tree of Life planted in the midst of the Garden of Eden. Because of man’s fall through original sin, immortality of soul and body is given to man only through faith in the God-Man Jesus Christ Who paid the penalty for our sins through His suffering, death, and shed blood, and who bodily rose from the grave.

    Scripture teaches that one day, because of Christ’s redemptive work, God will restore all of creation and there will be no violence in the animal kingdom anymore.

    Visit the author’s popular website, THE SCIENCE SUPPORTING CREATION

    Author of the popular Internet article, TRADITIONAL DOCTRINE OF HELL EVOLVED FROM GREEK ROOTS

    The author, Babu G. Ranganathan, has his bachelor’s degree with concentrations in theology and biology and has been recognized for his writings on religion and science in the 24th edition of Marquis “Who’s Who in the East.”

    • Mongoose

      Thank you.

    • Cat Casidy

      So the cats all get to starve or how does that work?

      • Mongoose

        That’s not it. The point is that Man should not be cruel and violent, because it isn’t necessary.

    • Notagod

      has god bestoweth the power of revelation within thou?

    • David Digi

      God is not real

      • Mongoose

        Whether you believe in God or not, the purpose of the teaching is that cruelty and violence on the part of Man are wrong.

        • David Digi

          Why should I take the teaching seriously when it’s no more credible them my opinion… Plus the bible is a horrendous book of murder and gennoacide, pretty much the last place I want to get my values.

          • Mongoose

            And sex. Don’t forget all that sex. It’s just that cruelty and violence are wrong and kindness is right. Especially if one is on the receiving end.

      • ⋚≶≶Rêverêche≷≷⋛〻

        1. We can’t actually prove we’re not inside a giant computer simulation, with programmer “gods.”

        2. The evolution of empathy is unrelated to the existence of a god.

        3. Bible is definitely a horrible book, but you haven’t exactly displayed any opinions that put you on a moral high ground yourself.

        • VoM80

          This David guy posts all day on a YT rat killing video arguing for burning such animals alive, and encouraging sadism. He’s completely wrong about rats not being protected, btw.

    • Mongoose

      Thank you for your effort to explain why violence and cruelty is so wrong and unnecessary.

  • Mongoose

    Think twice before you kill another creature.

    • mary.bullock4

      If you could use extra profit of about 50 bucks to 300 bucks on daily basis for doing simple work over internet from your couch at home for few h a day then try this…

    • David Digi

      Why? Then it might get away before I can kill it

      • Mongoose

        Why would you want to? Killing for survival is one thing. Killing just to kill is something quite different.

        • David Digi

          Because it’s a rat and it dies if it’s in my home

          • Mongoose

            I know that a lot of people share your feelings about that. However, I can’t imagine anything living in your home. The atmosphere must be too toxic.

          • David Digi

            What does that even mean? Is that supposed to be some kind of lame insult lol?

          • Mongoose

            :-) Take it however you like. Or don’t like.

          • David Digi

            I’d say the atmosphere of 3 cats roaming around wouldn’t be ideal for a rat so you’re onto something there

          • ⋚≶≶Rêverêche≷≷⋛〻

            Man, I hope you die of the plague.

    • mjacks2

      and die of hunger

      • Mongoose

        If you prefer not to be a vegetarian, so be it. killing to survive is acceptable for those that chose that. For those that eat animal products, including flesh foods, there are humane methods. Unfortunately, they are rarely practiced industry-wide.

      • disqus_hzJTto3tKZ

        Personally hunting and killing your food, are you? Or do you just pick it up at the store like everyone else who makes such hyperbolic comments…?

    • anna.dahl2
  • Fallopia Tuba

    Rats are awesome; I love their little hands.

    • David Digi

      Especially when they’re cut off

      • Mongoose

        Why do you seem to rejoice in cruelty?

        • David Digi

          No such thing as cruelty towards a rat, they are not protected

          • Mongoose

            One does not need to be protected to feel pain and fear. It’s the pain and fear that makes me feel sympathetic. No creature should die in pain and fear. Eliminate that, and it’s a whole different matter.

          • David Digi

            That’s your personal opinion, in mine, I put my home and family’s well being before the rats pain and fear, I’ll pick up whatever I got & beat it to death. Because it’s my home & I say so, world doesn’t revolve around your opinions. Should I feel bad for a bug who’s running away from me too? They’re pests in the home they have to be killed in my opinion

          • ⋚≶≶Rêverêche≷≷⋛〻

            Rats never killed anyone. Humans created a disgusting environment that fostered parasites and disease, which killed the rats as well as us. Medieval Western Europeans were filthy (they thought the bathing habits of the Norse and Middle Eastern were “effeminate”), and their deaths were on their own hands. Additionally, they killed cats en masse, causing a rodent explosion. Again, the fault of humans, not rats.

  • Odietamo

    My rats dream of going to the beach.

    • David Digi

      No they don’t

      • ⋚≶≶Rêverêche≷≷⋛〻

        I assume you’ve done the proper neurological research to rebut the claim? Or does it infringe on your sad little fantasy that your brain is more special than anyone else’s?

  • Alicia Valentin

    “So far, that kind of recording requires implanting tiny electrodes on
    very thin wires into the brain, which can’t be done with human subjects
    for ethical reasons, but it’s possible with rats”, yes, because apparently rats lives are less valuable then humans. Ugh.

    • David Digi

      Obviously they are less valuable , by a huge margin. Stop being unrealistic. Rats are the lowest form of mammal and are protected by no laws

      • Mongoose

        While I get your point, I think we need to keep in mind that the more we learn, the more proof we have that they are not insentient. They are strictly at our mercy, and that means that there are, and should be, ethical considerations in play.

        • David Digi

          Why should I care if it’s sentient? If it poses a threat in my home it dies,and no your family is the one at mercy from its diseases, and destruction, and food stealing, and pooping everywhere, and live in the walls, ect. But I suppose I should let these things happen out of kindness to the rat who does nothing but make a nusence? Noooo thanks

          • Mongoose

            I understand your point, and I agree. However, there has to be a better was of doing things than just hauling off and killing things.

            Of course, to be fair, my namesakes were brought to the Virgins to kill rats that were getting into the grain and cane. However, that was supposed to be a natural solution. Didn’t work out, but that was the rationale.

          • David Digi

            Well what do you presume i do if I see a rat in the house? you have very few options when you see one, and you can’t leave the room to get something else to take care of it or else it won’t be there when you get back. Gotta grab what you can, wether it’s a book, a bat, whatever. And also not only do the rats threaten the humans in my home but they likely threaten my 3 cats even more, that level of risk in the home just means I have to kill it in the quickest way possible IMO

          • Alicia Valentin

            Hypothetical speaking, by not allowing your 3 cats to do what comes naturally to them, which is kill, you are in fact contracting your previous statement. The value of having a cat in the first place is to kill pests, and to further your precious point, that is why you are a walking contradiction.

          • ⋚≶≶Rêverêche≷≷⋛〻

            Pssst. Read up on smallpox blankets.

      • ⋚≶≶Rêverêche≷≷⋛〻

        Rats are extremely intelligent, by mammal standards. How are you defining “low”? Humans have spread far more disease and wiped out many more species than rats could ever dream of, if that’s your rhetoric.

      • Barbara

        Human law has no bearing on the intrinsic value of anything. Human law (or at least US law) doesn’t even effectively protect the air we breathe, but try doing without it. Besides, laws and the people who write and enforce them can simply be wrong: slavery pops to mind, and here it required a Constitutional Amendment and a civil war to correct. White Europeans also pushed the Native Americans to the brink of extinction, and there were no laws to stop that – we took over the country and carved it up among ourselves, conveniently ignoring the human population that was here before we ever showed up! I am actually worried about you, David Digi, and more worried FOR the people around you, if you base your morals solely upon the law: you sound like a psychopath.

    • Mongoose

      I agree. Unfortunately, I can’t think of any way other way to perform that research.

  • Caseas

    < ?????? +dilbert +*********…..


  • yvvvvvvvv

    Hello, Anybody has ideas about where could find the original journal of this article?

  • yvvvvvvvv

    hello, anyone has ideas that where could find the original journal article of this article?


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