MIT Researchers Explore How Rats Think

Ant writes "A Nature News article explains that, after running a maze, rats mentally replay their actions backwards." From the article: "As the rats ran along the track, the nerve cells fired in a very specific sequence. This is not surprising, because certain cells in this region are known to be triggered when an animal passes through a particular spot in a space. But the researchers were taken aback by what they saw when the rats were resting. Then, the same brain cells replayed the sequence of electrical firing over and over, but in reverse and speeded up. 'It's absolutely original; no one has ever seen this before at all,' says Edvard Moser, who studies memory at the Norwegian University of Science and Technology in Trondheim."

Comments

Move over CS grads

[hobotron]

If a rat knows the difference between a Stack and a Queue, you better start updating your resume.

Interesting

[Belseth]

Sounds like it's a way of setting important memories. Being able to navigate a course is important to a rat's survival. It'd be interesting to see if this happens with all memories or just the most important for the rat to recall. Stress causes memories in humans to become more perminate. There was a study where people held their hand in ice cold water to see how it affected memory. The shock of the cold water increased retention dramatically. I'd be curious if the levels of stress hormones went up as well. Rerunning the memory may be a stress reaction to important information.

the learning possibilities

[TubeSteak]

The discovery could also help to explain why people tend to learn a new task quicker when they take short rests between each practice round. It suggests that eliminating such breaks could actually interfere with learning, and perhaps even explain why hyperactive children often have learning difficulties.

This may be less about ADD/ADHD kids than about teaching style in general.

Any teaching style that will appeal to a hyperactive child, will more than likely be engaging for a 'normal' student.

Though it might be a stretch to suggest this could be extended to understanding hyperactive kids. AFAIK, they usually have abnormally low levels of dopamine and/or seratonin in their brains, while the article posits that "The rerun [for mice] could coincide with a burst of the reward chemical dopamine, which is released in the brain when the animal finds food."

Maybe they can find some hyperactive mice to run the tests on?

How they think?

[neoform]

It's pretty simple, once they get the juice on someone, they squeal to the nearest narc.. obviously.

Never Before Has There Been A Comment Like This

[Doomedsnowball]

"It's absolutely original; no one has ever seen this before at all," says Edvard Moser.

Except for the rats, of course.

Real political science.

[www.sorehands.com]

MIT is studying politicians. They use rats since the rats won't pick the scientist's when they turn their backs.

Interestingly enough....

[ChrisGilliard]

The researchers found that some of the rats thought more about the maze than others. Here's a picture of two mice. The one on the left thought much more about his performance than the one on the right.

Re:interesting...

[Skreems]

Most creative thinkers already understand, at least intuitively, that the human brain will continue working on a problem even when a person is actively thinking about something else. How many programmers know that when you're beating your head against a problem, a good way to solve it is to go do something physical or repetitive, like play sports or video games or even sleep? Then when you come back, your brain has an answer for you, or at least has conceptualized the problem so you can get a better handle on it.

I don't know how much there is to officially back this up, but I think this is why OOP caught on so well, at least with some people. If you have a system made of interacting modular components, your brain doesn't have to conceptualize sections of some messy lines of ASM or C code... it can just use the constructs you've actually built into the system, so the "processing cost" of groking the system is much cheaper.

I suspect they will find the same true for people

[icecow]

Haven't most people walked through the halls of a unfamiliar building to their destination then stopped and reviewed how to get back out a few times (a movie in reverse sorta) in order to get it in their long term memory? or is it just me? I don't always do it, just when the path seemed complicated. I'd think doing this would be much more important to a mouse considering they have rival creatures towering over them like downtown buildings.

Whoa, I'm reading back my post and thinking WTF!

Re:brain == computer

[Ithika]

No, but when you die Netcraft confirms it.

back propagation learning algorithm

[S3D]

The result is also of keen interest to those who study artificial intelligence and try to teach computer systems or robots to learn through reward and punishment. Some such systems already work by playing back a sequence of moves so that the computer can identify at which point it made the trial or error.
It's called back propagation learning The algortihm is based on the error propagation backwards from the output nodes to the inner nodes of neural net.

Re:back propagation learning algorithm

[eMago]

It could also mean http://www.answers.com/topic/reinforcement-learnin g?method=22 (Wikipedia itself is currently down). Reinforcement Learning (RL) is about learning from reward - and about finding optimal sequences of action. Especially for learning sequences over time - like the rats - it is THE method of choice. And yes, Artificial Neural Networks (ANNs) are often used for representing the "optimal policy" in RL. The weights in those networks are then altered by the RL process.

You could describe the process in the rats brain as doing a "virtual policy search RL".

Pure Backpropagation for long sequences over time, on the other hand, is quite an intractable problem, because you have to feed so many time-states into the network.

Re:brain == computer

[strider44]

You should perhaps read a book called Gödel Escher Bach by Douglas Hofstadter if you haven't already, which develops and expands that theory. It's *starting* to get a bit old at the moment but it's still absolutely fascinating.

New Science?

[ThePopeLayton]

Sorry boys, But I have been studying Neuroscience for the last 3 years. Every lecture we have had on sleep, particullary REM, has taught that when you are sleeping your neurons will all re-fire in an organized manner. This is when your memories are "consolidated" from semi-long term to long term memories. This is why if you have had a particularly stressful day you can "re-live" that day in your dreams. However it has long been shown that "place cells" or neurons that store spatial location will fire in the direct same sequence in which they fired when the test subject was presented with a spatial puzzle. You can read about this in the book Neuroscience by Kandal.