People's Brains "Coupled" to Each Other in Good Conversation

Ever feel like you're really in sync with the person you're speaking with and can almost predict his or her words? We've probably all experienced this from time to time, and when it happens, there's good evidence that the brain patterns of the speaker and listener are virtually the same. A new study uses brain scans to explore this phenomenon called "neural coupling".

Sometimes the listener's brain pattern actually changed before the speaker's, which raises the possibility that the listener may actually have been predicting what the speaker was about to say.

Greg J. Stephens and his team at Princeton University had 11 people listen to a recording of a woman telling an "ad lib" story about when she was a high school freshman. The participants' brains were scanned using a fMRI scanner (the listeners were scanned while they were hearing the story, and the speaker's had been scanned while she recorded it). Afterwards, the listeners were quizzed on how well they understood the story.

The team found that the very same areas of the brain were active in both the speaker while she told the story and the listeners as they heard it. As expected, most of the time the listeners' brains showed a small delay, which makes sense, since there is a tiny lag between a speaker's formation of his or her thoughts and the listener grasping them. But sometimes the listener's brain pattern actually changed before the speaker's, which raises the possibility that the listener may actually have been predicting what the speaker was about to say.

Another remarkable finding was that the people who understood the story the best (those who scored the highest on the questionnaire following the tale) showed the strongest neural coupling with the speaker.

For all the skeptics out there, the researcher did a nice follow-up experience to illustrate that rather than just hearing what was being said, the listener's comprehension was really the basis of the phenomenon. The participants also listened to a story being told in Russian (none of the listeners spoke the language), and again their brain activity was compared to the speaker's. As expected, there was no neural coupling involved in this situation, which again suggests that understanding what is being said is really at the heart of the similarities in the brains of speaker and listener.

So for all the couples who can finish each other's sentences, there's a good chance that your brains are truly "coupled" as well.

The study was published in the July 26, 2010 online issue of Proceedings of the National Academy of Sciences.