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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."
When they can scale it up from lawyers to humans, we might have something useful to talk about.
"Flowers for Algernon" was the first association that popped up from the depths of my mind...
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.
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?
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...
A slashdotter who didn't build his own computer is like a Jedi who didn't build his own lightsaber.
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.
Revive the Constitution.
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.
The Tao of math: The numbers you can count are not the real numbers.
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.
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.