Scientists Build a Smarter Rat

destinyland writes "Scientists have engineered a more intelligent rat, with three times the memory length of today's smartest rats. Reseachers bred transgenic over-expression of the NR2B gene, which increased communication between the rat's memory synapses. Activating a crucial brain receptor for just a fraction of a second longer produces a dramatic effect on memory, as proven by the rat's longer memories of the path through a maze."

Comments

Needs much more work

[Anonymous Coward]

When they can scale it up from lawyers to humans, we might have something useful to talk about.

NIMH

[Rik Sweeney]

Mrs. Frisby will be pleased...

The rats' name is not 'Algernon', or is it?

[treczoks]

"Flowers for Algernon" was the first association that popped up from the depths of my mind...

Re:Spooky

[daveime]

Yeah, we'll all need to live longer so we can foil the plans of Pinky and the Brain.

Memory is an interesting thing

[BadAnalogyGuy]

Even the most forgetful person can be reminded of an event and recall it with vivid clarity. Alzheimer's sufferers can overcome some of the difficulties of the disease with a device like the Life Recorder.

So when we say that someone's (or some rat's) memory is improved, what exactly is improved? Is it the recall ability? If so, does that mean that the rat is somehow able to logically filter out unnecessary information to reach the important memory? Or does it mean that the rat's memory has been structured in a better way? Is it only a spatial thing, or can it work for any type of information?

As someone with a bad memory, I would be very interested in understanding how this actually works within the rat's brain.

Re:Memory is an interesting thing

[ikefox]

Well, the NR2B gene is encoding for a very common and well known receptor within both rat and human brains - the NMDA receptor. These receptors have been the target of the majority of recent studies into working memory and synaptic plasticity, or so-called "long-term potentiation". Basically, the NMDA receptor is the most likely cause of memory reinforcement. The idea is that when two neurons fire simultaneously, the connection between them is strengthened for a long period of time. That is, the post-synaptic neuron becomes more sensitive to input from the pre-synaptic neuron. This effect is input-specific, in that it is only effective between the two specific neurons involved, and no similar input from other pre-synaptic neurons is necessarily potentiated. Most LTP relies on the NMDA receptors to function, via the calcium ion channels within most synapses. This is why increasing the number of NMDA receptors would likely reflect a quantitative increase in memory. This isn't exactly breaking news - researchers have known about the NMDA receptors/NR2B gene for years, and I've seen studies from several years ago with the same approximate findings in animal models.

Faster Memory?

[Xebikr]

Activating a crucial brain receptor for just a fraction of a second longer produces a dramatic effect on memory

So they overclocked the rats? Cool!

Re:Faster Memory?

[new death barbie]

...whether some of the newly-created address space is unaddressable for reasons yet unknown.

You need a 64-bit rat to access all the extra memory space.

We already knew it worked for mice

[tgibbs]

Kind of old news; the first report that NR2B overexpression improves rodent performance in some behavioral tests of learning and memory was was published in 1999. The nice thing here is that the investigators now have it working in the rat, which is a more difficult animal for transgenic studies, and a better one for behavioral work and electrophysiology.

Nevertheless, it raises an interesting question: if intelligence can be increased by something so simple as an increase in the expression of a single NMDA receptor subunit, why hasn't it already happened? Presumably, there is a selective advantage to improved learning and memory. Presumably, there is some kind of downside that balances that selective advantage. Are there other behaviors for which the rat is impaired?

Re:We already knew it worked for mice

[John Hasler]

> Presumably, there is some kind of downside that balances that selective
> advantage.

Higher energy requirements would be a good bet.

Re:We already knew it worked for mice

[debrain]

Presumably, there is a selective advantage to improved learning and memory. Presumably, there is some kind of downside that balances that selective advantage. Are there other behaviors for which the rat is impaired

As you suggest, there are two possibilities why this advantage hasn't occurred naturally:

1. It adds no selective advantage;

2. The advantage is outweighed by the costs.

There is a third possibility, namely that the set of mutations necessary to give rise to this advantage are too improbable to occur (or perhaps even fundamentally impossible).

Based on no knowledge whatsoever, I suspect that there probably is some selective advantage to higher intelligence in rats, over long enough periods of time. I hypothesize that the rats lack the ability to effectively dissipate heat from a highly active brain, and concurrently those evolutions that allow more effective dissipation of heat (e.g. baldness) are contrary to (or have never occurred concurrent with) the selective advantage of the intelligence. Perhaps we will breed intelligent, bald rats.

Re:We already knew it worked for mice

[ortholattice]

As you suggest, there are two possibilities why this advantage hasn't occurred naturally:

1. It adds no selective advantage;

2. The advantage is outweighed by the costs.

There is a third possibility, namely that the set of mutations necessary to give rise to this advantage are too improbable to occur (or perhaps even fundamentally impossible).

Maybe there is a 4th possibility. Everyone seems to be focusing on "survivability", but once that is overcome, reproduction becomes important. Look at the ostentatious displays of some birds that have nothing to do with survivability or might even be detrimental to it. Maybe a highly intelligent rat simply becomes less interested in sex, or is less able to attract females who might prefer the dumb macho rats. I don't know if a comparison to humans has any validity, but the most intelligent of our species are not necessarily the ones reproducing the most (or in some cases at all). This is in spite of the fact that we are intelligent enough to understand logically what is necessary to propagate our genes. In terms of the long-term evolution of humans, intelligence doesn't seem to be one of the characteristics we are selecting for, for better or worse.

Actually I wonder what the downside is

[OeLeWaPpErKe]

After all, if more memory were that simple, surely evolution would have changed that gene by itself. If it were a tradeoff, that would be much more logical.

So what did these rats lose ? Do they have gaps in long term memory ?

I'd watch out for the "no free lunch" idea holding true here too.

Re:Actually I wonder what the downside is

[maxwell demon]

Maybe the trade-off is that their brain simply needs more energy, which isn't great when food availability is the main factor limiting reproduction. Or maybe, the better memory simply doesn't help the rats too much in their natural habitat. After all, natural selection doesn't favour long memories, it favours large effective reproduction rates. If long memory doesn't lead to higher effective reproduction rates, it won't be improved by natural selection.

Re:Actually I wonder what the downside is

[Anonymous Coward]

I've noticed that I have a very good semantic memory (memory of concepts), but a comparatively poor episodic memory (memory of events). I tend to remember patterns but not specific examples of those patterns.

I've wondered if there's some sort of trade off between the two. Instead of memory performance and other aspects of intelligence being a matter of capacity (where more is strictly better), it could be more of a matter of allocation of capacity (where there may be trade offs).

Re:Actually I wonder what the downside is

[Trent Hawkins]

After all, if more memory were that simple, surely evolution would have changed that gene by itself. If it were a tradeoff, that would be much more logical. So what did these rats lose ? Do they have gaps in long term memory ? I'd watch out for the "no free lunch" idea holding true here too.

Evolution decided that when creature has to eating nothing but rotting crap all it's life, it's best that the creature not be able to ponder on the matter.

at what cost?

[Lord Ender]

Due to his enhanced memory, the rat could not push her out of his mind. The memories refused to fade with time. The slightest sight or scent would cause him not just to remember his intense passion and total devotion, but also to relive it, as if she were still there with him. Moments later, as reality returned, he inevitably re-experienced that October afternoon when she left. The despair cut to the bottom of his soul in a way far more intense than the original break-up had been, as shock had initially numbed his pain. No more. His perfect memory of perfect happiness lifted him up so high, the inevitable fall came from an unimaginable height, and terminal velocity does not apply to emotions.

After enduring this torture for what seemed an eternity, he finally gave in, and resolutely marched toward the wire-framed cheese, her angelic body still vivid in his mind...

Other Rodent Upgrade Experiments

[Garrett Fox]

About eight years ago I read about a line of experiments that measurably increased rodents' performance in a set of memory and learning tasks. I believe the genetic change involved the NMDA receptor, but a quick search doesn't turn up an obvious link to that.

There was a report this September that gene therapy had been used to grant "full" color vision to colorblind monkeys, following on an earlier experiment that did the same thing to rodents. That is, the rodents were given three-color vision where they normally have two color receptor types. (Would that make them transrodents?) Apparently, the brain automatically adapts to having a new receptor type installed in the retina! And the same technique could be used on humans to grant us a fourth receptor type, maybe a UV receptor gotten from parrots or something. I'd volunteer to have this done to one eye. (The first comment on this article presents a dissenting view that just because the monkeys were able to distinguish colors in greater detail than before, that shouldn't be taken as proof that they "have full color vision". All the more reason to try it in a human!)

The rodents could be in combination with cyborg cats though, as seen in this 1995 report of recognizable images read directly from a cat's visual cortex.

Re:The world needs this....

[ktappe]

I wish there was a "-1, pathetically paranoid party pooper" mod..

I'm glad there's not, because this really is a dangerous thing. If one of these rats escapes we will be in for some hurting. Rats are already rather smart--they know what traps are and how to avoid them, for example. Go live in a rat-infested portion of a city and then tell us again anyone objecting to this experiment is "paranoid".

Re:I for one

[NotQuiteReal]

You might want to see a doctor if hearing a particular song causes you to lose balance. I'm not saying tumor or anything, but you might want to check it out.

Re:The world needs this....

[Gerafix]

The solution is easy, we just have to breed smarter cats and let them loose. What could possibly go wrong?

Re:The world needs this....

[russotto]

Go live in a rat-infested portion of a city and then tell us again anyone objecting to this experiment is "paranoid".

It's not a real problem. These rats with their superior maze-following ability will be nerds among rats, and thus will not reproduce in the wild.

Re:I for one

[Gilmoure]

Coarse strippers are rough!

Re:I for one

[pwfffff]

OMG! I can't believe I was actually on the internet when the FIRST EVER expression of displeasure towards an overused meme was posted! So fresh, so original, so... intelligent! You truly are a hero of the internet!!!

Thanks for standing up for us, the little guys, who see memes posted day after day but are unable to do anything about it. You, sir, have surely stopped, once and for all, this abuse of popular culture.

Re:The world needs this....

[Gilmoure]

They'll be busy playing D&D?

What ya gona do tonight?

[Forge]

What ya gona do tonight?

Same thing we do every night.

try to take over the world.!!!

Re:Spooky

[clone53421]

Most of the time, at least in the US, the term OTC is used to refer to non-prescription drugs that are stocked on the shelves.

Over-the-counter drug:

The term over-the-counter may be somewhat counter-intuitive, since, in many countries, these drugs are often located on the shelves of stores like any other packaged product. In contrast, prescription drugs are almost always literally passed over a counter from the pharmacist to the customer. Some drugs may be legally classified as over-the-counter (i.e. no prescription is required), but may only be dispensed by a pharmacy employee after an assessment of the patient's needs and/or the provision of patient education.

Re:I for one

[ae1294]

Thanks for standing up for us, the little guys, who see memes posted day after day but are unable to do anything about it. You, sir, have surely stopped, once and for all, this abuse of popular culture.

I for one, welcome our new meme overlords!