This is a map of someone’s brain, showing roughly which areas respond when they hear different words. For example, there’s a small area in the middle frontal gyrus that reliably responds to hearing the word ‘top’. But it’s not just one word, one location. A single word can activate a whole range of different brain regions. So, we find the word ‘top’ in a bit of brain that seems to respond to words associated with clothing and appearances. But also, here, with numbers and measurements. And here, with buildings and places. We usually think of language as being restricted to certain sections like the temporal lobe. So researchers were surprised to find activity all across the brain, and in both hemispheres. The map was made by scientists at the University of California, Berkely. They put volunteers in an MRI scanner and had them listen to stories for 2 hours. …She digs back in the front again – deep, deep – and she pulls out a pack of matches
that had been laundered at least once… By monitoring blood flow to different parts of the brain they worked out which places were responding to the meaning of the words: the semantics. They found that different bits of the brain responded to different kinds of words and concepts. And they could group them into rough
categories, shown here by the different colours. Dark green bits, for example, were most activated by words to do with numbers, red bits by social words. Here, in the right temporoparietal junction, this speck of brain, just a few millimetres across, was found to respond to words like
‘wife’, ‘mother’, ‘pregnant’ and ‘family’. And this bit just next door responds to some of the same social words, like ‘family’ and ‘wife’, but also words to do with places and people like ‘house’ and ‘owner’. Generally, the concepts represented in each brain region relate to other functions that scientists already know about; so, words to do with how things look, such as ‘stripes’, are likely to be found near the visual cortex. And although each individual’s map is different, looking at these three brains, it’s clear that different people have the same kinds of concepts in the same kinds of places. This is the first time we’ve been able to
map the semantic systems of the brain in such detail – discovering that words are grouped by meaning, and revealing just how complicated, and widespread, the word maps in our heads really are. And, the brain map is available online for anyone to explore.