CAMBRIDGE, Mass. In the 1983 movie "A Man with Two Brains," Steve Martin kept his second brain in a jar. In reality, he had two brains inside his own skull as we all do, one on the left and one on the right hemisphere. When it comes to seeing the world around us, each of our two brains works independently and each has its own bottleneck for working memory.
Normally, it takes years or decades after a brand new discovery about the brain for any practical implications to emerge. But this study by MIT neuroscientists could be put to immediate use in designing more effective cognitive therapy, smarter brain games, better "heads up displays," and much more. The study will appear on the website of the Proceedings of the National Academy of Sciences on Monday, June 20, 2011.
Researchers have known for over a hundred years that we can only hold about four things in our minds at once. This capacity limitation of our working memory (our mental sketchpad) varies somewhat among individuals, and the more you can hold in mind at once, the more complex your thoughts and the higher your IQ tends to be. But although this limitation is a fundamental feature of cognition and intelligence, researchers knew nothing about its neural basis.
Monkeys, amazingly, have the same working memory capacity as humans, so Earl Miller, the Picower Professor of Neuroscience in MIT's Picower Institute for Learning and Memory, and Timothy Buschman, a post doctoral researcher in his lab, investigated the neural basis of this capacity limitation in two monkeys performing the same test used to explore working memory in humans. First the researchers displayed an array of two to five colored squares, then a blank screen, and then the same array in which one of the squares changed colored. The task was to detect this change and look at the changed square.
As the monkeys performed this task, Buschman recorded simultaneously from neurons in two brain areas relate
|Contact: Marta Buczek|
Massachusetts Institute of Technology