Personalized Dream Scan

If you’re one of the many people who have trouble remembering your dreams, Japanese researchers may have found a way to decode them for you. By monitoring the brain’s visual centers during sleep, it may someday be possible to reconstruct dream content, even if it’s forgotten upon awakening.

The technique uses a functional magnetic resonance imaging scanner (fMRI) which measures neuronal activity in the brain by detecting changes in localized blood flow. Participants were allowed to doze off and, just as they started to fall asleep, were awakened and asked to describe what they had been “seeing.” Over the course of the test, this procedure was repeated a minimum of 200 times at approximately six minute intervals. Responses were categorized and similar images were shown to participants while they were awake, again recording fMRI images of brain activity at the corresponding moment in time.

By matching up the fMRI images with the categories, the computer could be “trained” to pick out the brain signature of each one. In a second round of testing, the system predicted dream visualizations with an accuracy of about 60 percent.