The content of dreams provides a complicated, hazy window into a person’s mind: What’s the meaning of all that visual junk that slips to the surface from the subconscious and usually lacks any sort of logical narrative? And why do people dream the things they do, when they do?
Researchers in Japan are chipping away at some of these questions with a new MRI-based technique they say predicts the content of their subjects’ dreams with up to 60% accuracy. The BBC reports:
The team used MRI scans to monitor three people as they slept. Just as the volunteers started to fall asleep inside the scanners, they were woken up and asked to recount what they had seen. Each image mentioned, from bronze statues to keys and ice picks, was noted, no matter how surreal. This was repeated more than 200 times for each participant.
The researchers used the results to build a database, where they grouped together objects into similar visual categories. For example, hotel, house and building were grouped together as “structures”.
The scientists then scanned the volunteers again, but this time, while they were awake and looking at images on a computer screen. With this, they were able to see the specific patterns of brain activity that correlated with the visual imagery.
After the connections were established between visual imagery and brain activity, the researchers monitored the participants’ brains during additional rounds of sleep tests, noting what the brain activity looked like and linking it with the correlated visual imagery. When the participants woke up, their reports on what they were dreaming corresponded with the hypotheses of the researchers 60% of the time.
Mark Stokes, an Oxford cognitive neuroscientist, told the BBC that the research portended a future where one day there would be “dream-reading machines.” “It’s obviously a long way off, but there is no reason why not in principle,” he said.
But such a machine would have to be custom built for each person (a new cottage industry?), since it’d need the data on what individual brain activity looks like. Stokes added, “You would never be able to build something that could read other people’s thoughts without them knowing about it, for example.”