Scientists Eavesdrop Inside the Mind

[TECH NEWS]

In a small study that might sound like science fiction, researchers could predict what people were hearing based on their brain activity. “As you listen to a sound, it activates certain parts of the auditory cortex of your brain,” said Brian Pasley, a UC Berkeley neuroscientist and lead author of the study published Jan. 31 in PLoS Biology. “We’re interested in how the brain converts sound into meaning, so we looked at an early step in a long process.” To study the relationship between sound and brain activity, Pasley and his team enlisted the help of 15 epilepsy patients who had electrodes implanted in their brains. As the patients listened to a series of words, such as “structure,” “doubt” and “property,” the researchers recorded their brain activity. They then developed a computer model to match the sounds with the brain signals. “You can think of the brain as a piano and the recordings as the keys,” said Pasley. “You could turn off the sound and an expert pianist would still have a good idea of what note was being produced. We’re trying to be the expert pianist.” When the researchers relied on the model to hear what the patients heard, they got an eerie version of the actual word. Pasley hopes to fine-tune the model to discern different types of words, and even their meanings.

Jan. 31, 2012, ABC News