Last year researchers reported they were able to use real-time images of a person’s brain activity to tell what version of an ambiguous shape they were looking at. Now Leun Otten and colleagues report that they can use measures of the brain’s surface electrical activity to predict whether someone will remember a word that they’re about to look at.
Participants were repeatedly presented with a symbol and then a word. The symbol indicated whether the participant had to judge if the ensuing word was a living thing, or if they had to decide whether its first and last letters were in alphabetical order. From the brain activity that occurred after the symbol, Otten’s team found that they could tell whether participants would remember the ensuing word when it was presented to them again 45 minutes later. Specifically, more negative electroencephalographic waveforms at the front of the brain after a symbol was shown, indicated the ensuing word was more likely to be remembered later.
“These findings demonstrate that neural activity preceding a stimulus event can influence memory for the event up to at least 45 minutes later”, the researchers said. The finding adds to previous research by showing that it’s not only brain activity elicited by a to-be-remembered stimulus that is important. Preceding brain activity “that in some sense provides a ‘neural context’ for the event”, is also crucial, the researchers explained.
Lead researcher Leun Otten said: “It sounds a bit like clairvoyance in the sense that we’re able to predict whether someone will remember a word before they even see it. That’s really new – scientists knew that brain activity changes as you store things into memory but now we have found brain activity that tells how well your memory will work in advance”. Spooky.
Otten, L.J., Quayle, A.H., Akram, S., Ditewig, T.A. & Rugg, M.D. (2006). Brain activity before an event predicts later recollection. Nature Neuroscience. In Press. DOI: 10.1038/nn1663.