Friday, October 23, 2009

Jonah Lehrer - Small, Fury, and Smart

Cool article from Nature by Jonah Lehrer. Deric Bownds uploaded the article - and a big THANKS to him for that!

It appears that mice can be genetically engineered to be smarter, but at a cost. This should serve as a warning to all the transhumanists who think the human brain and body can be engineered to be bigger, better, smarter.
Ten years ago, Joe Tsien eased a brown mouse, tail first, into a pool of opaque water. The animal squirmed at first; mice don’t generally like getting wet. But once released, it paddled in a wide circle, orienting itself by the array of coloured shapes hung above the pool. Within seconds, the mouse headed straight for the safety of a small platform hidden just beneath the water’s surface.

Most mice require at least six sessions before they can remember the location of the platform in a Morris water maze. But this animal needed just three.

Tsien, based at Princeton University in New Jersey at the time, named his creation Doogie after the teenage genius in the television programme Doogie Howser, MD. The work was one of the earliest examples of neuroscientists using genetic engineering to generate cognitively enhanced animals in a bid to understand memory and learning.

“There’s something magical about taking a mind and making it work better,” says Alcino Silva, a professor of neuroscience at the University of California, Los Angeles, and one of the pioneers in the field of enhanced cognition.

Researchers have now created or identified at least 33 mutant mouse strains that, like Doogie, have enhanced cognitive abilities. The animals tend to learn faster, remember events longer and solve complex mazes better than ordinary mice. And because the molecular pathways used in the brain to form long-term memories are almost identical in humans and rodents, the hope is that the work will inform research into treatments for a wide variety of learning and memory problems, from dyslexia to dementia.
Sounds promising, eh? But what might the risks be?
Little is known about the side effects and tradeoffs of both the current usage or the drugs in development, but initial clues offered by smart mice raise concerns. The Hras strain developed in Silva’s lab might be good at learning, but its fear response for a relatively benign stimulus would be counterproductive for a wild mouse. Its enhanced memory is both a blessing and a burden. Silva cites other strains of smart mice that excel at solving complex exercises, such as the Morris water maze, but that struggle with simpler mazes. “It’s as if they remember too much,” he says — possibly taking in irrelevant information such as the position of windows or lights but missing the big clues.

Farah sees a parallel between these mice and one of the few case studies of an individual with profoundly enhanced memory. In the early 1920s, the Russian neurologist Alexander Luria began studying the learning skills of a newspaper reporter called Solomon Shereshevsky, who had been referred to the doctor by his editor. Shereshevsky had such a perfect memory that he often struggled to forget irrelevant details. After a single read of Dante’s Divine Comedy, he was able to recite the complete poem by heart. Although this flawless memory occasionally helped Shereshevsky at work — he never needed to take notes — Luria also documented the profound disadvantages of such a capacious memory. Shereshevsky, for instance, was almost entirely unable to grasp metaphors, as his mind was so fixated on particulars. When he tried to read poetry, for example, “the obstacles to his understanding were overwhelming”, Luria wrote in his book The Mind of a Mnemonist. “Each expression gave rise to a remembered image; this, in turn, would conflict with another image that had been evoked.”
Read the whole fascinating article.

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