Recording Dreams

(Photo: Kaptain Kobold vis Flickr)

Imagine waking up from a vivid, wonderful dream that you can play back for others just like a video.

Recent work by California researchers could pave the way to reproduce and play back the movies in our minds that is, our dreams and memories.

Members of the research team at the University of California, Berkeley served as test subjects in their own study.

While sitting in an functional Magnetic Resonance Imaging (fMRI) scanner, they watched two separate sets of Hollywood movie trailers while the fMRI measured blood flow through the visual cortex, the part of our brains that processes visual information.

Smoothed view of brain showing visual cortex (in orange and yellow) (Photo: Mark Lythgoe & Chloe Hutton-Wellcome Images)

Since the brain is so complex to study as a whole, computers with the team’s special programming were used to divide the brain into small, three-dimensional cubes known as volumetric pixels, or “voxels.”  Each individual “voxel” described how shape and motion information in the viewed movie was mapped into brain activity.

The subject’s brain activity was then recorded for each set of videos they watched.

From the first set of videos the brain activity data was fed into a program that learned, on a second by second basis, how to associate visual patterns contained within the movie with the corresponding brain activity.

Then the brain activity created by the second set of clips was fed into the computer to test the team’s movie reconstruction algorithm, which contained some 18 million seconds of random YouTube videos. By scanning this tremendous amount of video, the reconstruction program was able to predict the brain activity that each film clip would most likely evoke in each subject.

Finally, the 100 clips that the computer program decided were most similar to the clip that the subject had probably seen were merged together to produce a blurry yet continuous reconstruction of the original movie.

With further study and experimentation, researchers hope the practical applications of this technology will also lead to a better understanding of what goes on in the minds of people who cannot communicate verbally, such as stroke victims, coma patients and those with neurodegenerative diseases.

The study has been published online in the journal “Current Biology.”