Scientists from the University of Cambridge have discovered the building blocks allowing us to understand spoken language in real time.
A new study, published in Proceedings of the National Academy of Sciences of the United States of America (PNAS), developed novel computational models of the meanings of words, and subsequently tested these directly against real time brain activity in volunteers.
“Our ability to put words into context, depending on the other words around them, is an immediate process and it’s thanks to the best computer we’ve ever known: the brain in our head. It’s something we haven’t yet managed to fully replicate in computers because it is still so poorly understood,” said Lorraine Tyler, Director of the Centre for Speech, Language and the Brain at the University of Cambridge, which ran the study.
By saying a phrase and monitoring how a volunteer’s brain responded, the researchers could track the dynamic patterns of information flow between critical language regions in the brain.
The study published under the University of Cambridge, highlighted “the rapid comprehension of speech is a remarkable but poorly understood human capacity. Central to this process is the integration of the meaning of each word, as it is heard, into the listener’s interpretation of the utterance.”
For example, when word A is heard, it primes the brain to form rules on how it interprets the next world in the sentence, therefore the brain understands that the following word, word B, is going to be related to word A. The study shows that these rules directly effect the understanding of the next word in the sentence, revealing the natural mechanism underpinning this essential property of spoken language. Human ability to combine sequences of words into meaningful expressions, millisecond by millisecond as the speech is heard.
“The way our brain enables us to understand what someone is saying, as they’re saying it, is remarkable,” said Professor Tyler. “By looking at the real time flow of information in the brain we’ve shown how word meanings are being rapidly interpreted and put into context.”