19 March 2009
"The brain's center of memory and navigation, once considered too disorganized to decode, may soon be unlocked. Using a brain scanner, researchers were able to determine the location of people standing in a virtual room from the activity in their brains.
"We could read their spatial memories, so to speak," said study co-author Eleanor Maguire, a University College, London, cognitive neuroscientist. "There must be a structure to how this is coded in the neurons. Otherwise we couldn't have predicted this."
Maguire's team focused on the hippocampus, a region of the forebrain responsible for processing spatial relationships and short-term memories. As people move, hippocampal activation helps them know where they are. In Alzheimer's patients, disorientation and memory loss go hand in hand...
Maguire's study, published Thursday in Current Biology, challenges that notion. And though it's far too soon to pull memories directly from a brain, the findings suggest future avenues of research on Alzheimer's and other forms of dementia.
"How these millions of hippocampal neurons work is a fundamental question in neuroscience," said Maguire. "We still don't know how the hippocampal neural code is organized to support memory and activation."
The researchers used an fMRI machine to measure hippocampal blood flow in four subjects who navigated a room in virtual reality. They focused on groups of neurons identified by Maguire in an earlier study of London taxi drivers, whose hippocampi were hyperdeveloped by years of mental navigation through the city's mazelike streets.
After analyzing activation patterns and correlating them with a record of test subjects' movements, Maguire's team found that patterns could actually be used to predict location."
By Brandon Keim
From Denny: Pretty wild stuff! While they are still a long way from fully understanding the complete process of laying down memory or even how memory deteriorates, this small study is an intriguing first step.