Thinking of a simple word such as apple creates a unique response in our minds that can be captured by brain scans.
Machines could also soon be able to understand hundreds of complex thoughts, because they can predict what they will look like in our minds, according to researchers at Carnegie Mellon University, in Pittsburgh, whose study is published in the journal Science tomorrow.
The scientists developed a computer system which can accurately forecast what activity patterns will be created in our brains by certain words.
They “trained” the machine to recognise the unique images created by thinking of 60 nouns associated with senses, including sight, touch, taste or smell.
The model was also taught how millions of English words are used in practice
In tests on nine volunteers the computer could accurately predict what brain patterns would be created by simple nouns for which it had never seen images.
“We believe we have identified a number of the basic building blocks that the brain uses to represent meaning,” said Tom Mitchell, a computer scientist, who helped to lead the study.
These building blocks could be used to predict patterns for any concrete noun, he added.
Marcel Just, a professor of psychology at the university, said the computer model gave a clearer insight than previously existed into how humans think.
“We are fundamentally perceivers and actors,” he said.
“So the brain represents the meaning of a concrete noun in areas of the brain associated with how people sense it or manipulate it.
"The meaning of an apple, for instance, is represented in brain areas responsible for tasting, for smelling, for chewing. An apple is what you do with it.”
The scientists hope that their work could eventually lead to the use of brain scans to identify a range of thoughts and be used in the study of conditions like autism or schizophrenia.
