20 June 2011

The Matrix reality: Scientists successfully implant artificial memory system

It seems the sci-fi industry has done it again. Predictions made in novels like Johnny Mnemonicand Neuromancer back in the 1980s of neural implants linking our brains to machines have become a reality.
Back then it seemed unthinkable that we’d ever have megabytes stashed in our brain as Keanu Reeves’ character Johnny Mnemonic did in the movie based on William Gibson’s novel. Or thatThe Matrix character Neo could have martial arts abilities uploaded to his brain, making famous the line, “I know Kung Fu.”   (Why Keanu Reeves became the poster boy of sci-fi movies, I’ll never know.)  But today we have macaque monkeys that can control a robotic arm with thoughts alone. We have paraplegics given the ability to control computer cursors and wheelchairs with their brain waves. Of course this is about the brain controlling a device. But what about the other direction where we might have a device amplifying the brain? While the cochlear implant might be the best known device of this sort, scientists have been working on brain implants with the goal to enhance memory. This sort of breakthrough could lead to building a neural prosthesis to help stroke victims or those with Alzheimer’s. Or at the extreme, think uploading Kung Fu talent into our brains.
Decade-long work led by Theodore Berger at University of Southern California, in collaboration with teams from Wake Forest University, has provided a big step in the direction of artificial working memory. Their study is finally published today in the Journal of Neural Engineering. A microchip implanted into a rat’s brain can take on the role of the hippocampus—the area responsible for long-term memories—encoding memory brain wave patterns and then sending that same electrical pattern of signals through the brain. Back in 2008, Berger told Scientific American, that if the brain patterns for the sentence, “See Spot Run,” or even an entire book could be deciphered, then we might make uploading instructions to the brain a reality. “The kinds of examples [the U.S. Department of Defense] likes to typically use are coded information for flying an F-15,” Berger is quoted in the article as saying.
In this current study the scientists had rats learn a task, pressing one of two levers to receive a sip of water. Scientists inserted a microchip into the rat’s brain, with wires threaded into their hippocampus. Here the chip recorded electrical patterns from two specific areas labeled CA1 and CA3 that work together to learn and store the new information of which lever to press to get water. Scientists then shut down CA1 with a drug. And built an artificial hippocampal part that could duplicate such electrical patterns between CA1 and CA3, and inserted it into the rat’s brain. With this artificial part, rats whose CA1 had been pharmacologically blocked, could still encode long-term memories. And in those rats who had normally functioning CA1, the new implant extended the length of time a memory could be held.
The next step is to test the device in monkeys, and then in humans. Of course at this early stage a breakthrough like this brings up more questions than solutions. Memory is hugely complex, based on our individual experiences and perceptions. If we have the electrical pattern for the phrase, See Spot Run, mentioned above, would this mean the same thing for you as it does for me? How would such a device work within context? As writer Gary Stix asked in the Scientific American article, “Would “See Spot Run” be misinterpreted as laundry mishap instead of a trotting dog?” Or as the science journalist John Horgan once put it, you might hear your wedding song, but I hear a stale pop tune.
We are provided with the same structural blueprint for our brains, but its circuitry is built from experience and genetics, and this is a tapestry unique to each of us. Something that many scientists feel we’ll never be able to fully crack and decode, let alone insert into it an experiential memory.

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