Harry Potter swoops around on his broom, faces the bully Malfoy and later runs into a three-headed dog. For scientists studying brain activity while reading, it’s the perfect excerpt from the young wizard’s many adventures to give their subjects.
Reading that section of “Harry Potter and the Sorcerer’s Stone” activates some of the same regions in the brain that people use to perceive real people’s actions and intentions. Scientists then map what a healthy brain does as it reads.
Most neuroscientists painstakingly have tracked how the brain processes a single word or sentence, looking for clues to language development or dyslexia by focusing on one aspect of reading at a time. But reading a story requires multiple systems working at once: recognizing how letters form a word, knowing the definitions and grammar, keeping up with the characters’ relationships and the plot twists. Measuring all that activity is remarkable, said Georgetown University neuroscientist Guinevere Eden, who helped pioneer brain-scanning studies of dyslexia but wasn’t involved in the new work.
No turning pages inside a brain-scanning MRI machine; you have to lie still. So at Carnegie Mellon, eight adult volunteers watched for nearly 45 minutes as each word of Chapter 9 of “Harry Potter and the Sorcerer’s Stone” was flashed for half a second onto a screen inside the scanner.
The research team analyzed the scans, second by second, and created a computerized model of brain activity involved with different reading processes. The research was published on Wednesday by the journal PLoS One. “For the first time in history, we can do things like have you read a story and watch where in your brain the neural activity is happening,” said senior author Tom Mitchell, director of Carnegie Mellon’s Machine Learning Department.
