Can Brain Scans Detect Memory?
The functional magnetic resonance imagery scanner (fMRI) is proving to be an exceptional and valuable tool for neuroscientists in trying to map out brain patterns and the paths the brain takes to process certain functions.
Recently the MRI has been used to read a person’s mind by detecting a person’s location in a virtual environment. Subjects were shown a building on a screen and were asked to navigate through the rooms in the building as researchers decoded their location. The researchers were able to read exactly where their subjects were at the time in their virtual tour.Â The neuroscientists, from the University College London, believe that it may be possible, with more practice using the technology, that eventually they may even be able to detect memories of past events from a human brain.
Dr. Eleanor Maguire, who led the research team, had their scanner trained on the hippocampus region of the brain, where memories are formed and stored. In animals, specialized cells in the hippocampus fire off regularly as the animal moved from place to place. In order for these firing patterns to be read, Maguireâ€™s team adapted a computer technique that had previously been used to predict what a person was looking at, and even what they intended to do with that item.
According to Maguire, past research looked at predictable areas of the brain, whereas this study was more challenging. â€œThe visual cortex is very interesting but quite well behaved, whereas the hippocampus is a bit more mysterious,â€ she says. Place cells are random throughout the hippocampus, showing no obvious arrangement.
For this study, the brains of four young men were scanned as they moved around eight different locations, four different but equal locations in two differently colored rooms. They were told to look down at the floor when they go to the designated areas so their brain could not give away their exact spot. When the computer analyzed the activity they found predictable patterns in each of their hippocampus. Because of the predictability, the researchers were able to determine the locations each of the men were in.
â€œThis is a very interesting case because it was previously believed impossible to decode [spatial] information,â€ says John-Dylan Haynes, a neuroscientist at the Bernstein Center for Computational Neuroscience in Berlin, Germany. â€œThere must be some hidden structure in the spatial organization of cells with activity related to each of the places in the environment,â€ agrees Edvard Moser, a neuroscientist at the Norwegian University of Science and Technology in Trondheim.
The fMRI scanner resolves the activity of thousands of neurons at a time, so pinning down a specific location, or other types of memories may be more difficult. Haynes says, â€œOne day a new imaging technique could come along and you’d be at the right place to decode even in these challenging cases,â€ he adds.
Maguire isnâ€™t waiting for new technology, however. Her team is already investigating the possibility of reading more vivid memories of movement and events. We’ve done some work about how the hippocampus is involved in planning the future â€“ where you’re going and what you’re doing,â€ she says. It all shows up on brain scans. “By looking at activity over tens of thousands of neurons, we can see that there must be a functional structure â€“ a pattern â€“ to how these memories are encoded,” Maguire said. “Otherwise, our experiment simply would not have been possible to do.”
Although computational neuroscience and systems biology are still a ways away from developing the technology to read minds, the tools today can read trends. â€œUnderstanding how we as humans record our memories is critical to helping us learn how information is processed in the hippocampus and how our memories are eroded by diseases such as Alzheimer’s,â€ added Maguire.
About the author:
Ron White is a two-time U.S.A. Memory Champion and memory expert. As a memory speaker he travels the world to speak before large groups or small company seminars, demonstrating his memory skills and teaching others how to improve their memory, and how important a good memory is in all phases of your life.
Fox News â€“ Brain Scans Can Read Memories, Scientists Find: http://www.foxnews.com/story/0,2933,509141,00.html
New Scientists â€“ Brain Scans Reveal Memories of Where Youâ€™ve Been: http://www.newscientist.com/article/dn16751-brain-scan-reveals-memories-of-where-youve-been.html