Mind may be ‘read’
It may be possible to “read” a person’s memories just by looking at his/her brain activity. A study by scientists in Britain shows that memories are recorded in regular patterns.india Updated: Mar 13, 2009 19:04 IST
Wellcome Trust scientists in Britain say that it may be possible to “read” a person’s memories just by looking at his/her brain activity, as a study conducted by them has shown that memories are recorded in the regular patterns.
Demis Hassabis and Professor Eleanor Maguire at the Wellcome Trust Centre for Neuroimaging at University College London (UCL) say that their study has shown that how the hippocampus—a small brain area which is crucial for navigation, memory recall and imagining future events—records memory.
The researchers say that when people move around, neurons known as “place celles” are activated in the hippocampus to tell them where they are.
Hassabis, Maguire and their colleagues used an fMRI scanner, which measures changes in blood flow within the brain, to examine the activity of these places cells as a volunteer navigated around a virtual reality environment.
They later used a computer algorithm to analyse the data.
"We asked whether we could see any interesting patterns in the neural activity that could tell us what the participants were thinking, or in this case where they were. Surprisingly, just by looking at the brain data we could predict exactly where they were in the virtual reality environment. In other words, we could ''read'' their spatial memories," says Professor Maguire, a Wellcome Trust Senior Research Fellow.
Previous studies in mice have demonstrated that spatial memories—how people remember where they are—are recorded in the hippocampus.
Those experiments, however, implied that there was no structure to the way that these memories are recorded.
Hassabis and Maguire say that their current study seems to overturn that school of thought.
"fMRI scanners enable us to see the bigger picture of what is happening in people''s brains. By looking at activity over tens of thousands of neurons, we can see that there must be a functional structure – a pattern – to how these memories are encoded. Otherwise, our experiment simply would not have been possible to do," she says.
Professor Maguire believes that the new findings may help devise a way to see how actual memories are encoded across the neurons, looking beyond spatial memories to more enriched memories of the past or visualisations of the future.
"Understanding 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. It''s also a small step towards the idea of mind reading, because just by looking at neural activity, we are able to say what someone is thinking," added Demis Hassabis.
A study led by Professor Maguire several years ago showed that, in London taxi drivers, an area to the rear of the hippocampus was enlarged, suggesting that area to be involved in learning location and direction.
In the latest study, the researchers found that the patterns relating to spatial memory were located in the same area, suggesting that the rear of the hippocampus plays a key role in representing the layout of spatial environments.
A research article on the study has been published in the journal Current Biology.