Brain imaging reveals mental movies

Sometimes life really does imitate art. In the 1980s sci-fi classic Brainstorm, scientists recorded a person’s thoughts and sensations so that others could experience them. While science is decades from that achievement, it may be on its way, thanks to a cutting-edge blend of brain imaging and computer simulation.

Scientists at the University of California said recently that they might one day be able to tap into the mind of a coma patient or allow people to watch their own dreams on YouTube.

Using functional magnetic resonance imaging, also known as fMRI, in conjunction with computational models, they decoded and reconstructed people’s dynamic visual experiences – in this case, watching Hollywood movie trailers. For now, the technology can only reconstruct movie clips people have already viewed. However, the breakthrough paves the way for reproducing the movies inside our heads that no one else sees, such as dreams and memories.

Previously, the group recorded brain activity in the visual cortex while a subject viewed black-and-white photographs. A computational model was built that enabled them to predict with overwhelming accuracy which picture the subject was looking at.

In the latest experiment, published online Sept. 22 in Current Biology, the team actually decoded brain signals generated by moving pictures. The work involved feeding 18 million seconds of random YouTube videos into the computer program so it could predict the brain activity that each clip would most likely evoke. The 100 clips that were most similar to the one the subject saw were merged to produce a blurry, continuous reconstruction of the original movie.

Members of the research team served as subjects for the experiment, because the procedure requires volunteers to remain still inside the MRI scanner for hours at a time.

Eventually, practical applications of the technology could include a better understanding of stroke victims, coma patients and people with neurodegenerative diseases.