A new collaborative study has discovered the process through which the brain stores the numerous intentions.
John-Dylan Haynes, a researcher from the Max Planck Institute for Human Cognitive and Brain Sciences, who conducted the study in collaboration with researchers from London and Tokyo, said that their findings became possible due to a new combination of functional magnetic resonance imaging and sophisticated computer algorithms.
The researchers let the subjects freely and covertly choose between two possible tasks - to either add or subtract two numbers – and then asked them to hold in mind their intention for a while until the relevant numbers were presented on a screen. <b1>
They were able to recognise the subjects intentions with 70 per cent accuracy based alone on their brain activity, even before the participants had seen the numbers and had started to perform the calculation. This ensured that the intention itself was being read out, rather than brain activity related to performing the calculation or pressing the buttons to indicate the response.
"It has been previously assumed that freely selected plans might be stored in the middle regions of the prefrontal cortex, whereas plans following external instructions could be stored on the surface of the brain. We were able to confirm this theory in our experiments", Haynes explained.
The trick by which the invisible is made visible lies in a new method called "multivariate pattern recognition", in which a computer is programmed to recognise characteristic activation patterns in the brain that typically occur in association with specific thoughts.
The study also revealed that different regions of the prefrontal cortex perform different operations, with regions towards the front of the brain storing the intention until it is executed.
"The experiments show that intentions are not encoded in single neurons but in a whole spatial pattern of brain activity", says Haynes.
"Intentions for future actions that are encoded in one part of the brain need to be copied to a different region to be executed," adds the researcher.
These findings published in the online edition of Current Biology raises hope for improvement of clinical and technical applications.