If you’ve ever wondered where exactly words are in your brain, scientists from the University of California at Berkeley have something to show you. In a paper published Wednesday (April 27) in the journal Nature (paywall), researchers describe the results of an experiment where they had test subjects listen to The Moth Radio Hour for two hours each. While the show played, they recorded the listener’s reaction using an fMRI machine. Their results show what specific parts of the brain react to different groups of words.
The researchers organized words heard in the show into twelve groups based on meaning. For example, they created a “numeric” group for number words and a “violent” group for words implying conflict. They then divided the brain into small regions that activate together when hearing a word. By cross-referencing these two datasets they were able to identify the correlations between the meanings of words and the parts of the brain that react to them.
Though the they only tested seven individuals, the fMRI data showed that all their reactions were similar. The authors speculate this could be due to common upbringing, but it may also indicate that there is a biological explanation for how meaning is organized in the brain.
The authors used their data to create a three-dimensional model of what regions are associated with which meanings. They’ve made that model available online. Try clicking around in the brain to see the individual clusters of words. Also “unfold” the brain to see what words are lurking inside those gray folds.