The intimate imaginings of our minds are exactly that – intimate. We have no idea what others may or may not see in their mind's eye. But now, scientists have developed a way to interpret these mental pictures by looking at brain wave patterns.
In a study published in Communications Biology, researchers from Osaka University tweaked existing electrocorticogram technology – which detects electrical activity in the brain – to capture people’s brain waves as they mentally pictured an image. They were then able to determine what the participants were imagining, even when they were looking at something else.
“Attention is known to modulate neural representations of perceived images,” lead author Ryohei Fukuma said in a statement.
“However, we didn’t know whether imagining a different image could also change these representations.”
The participants – nine epilepsy patients who already had electrodes fitted in their brains – were shown images while being instructed to picture something else entirely, such as a face, word, or landscape.
Researchers could then record the electrical activity in their brains in real-time using the electrocorticogram technique. They found a marked distinction between the imagined image and the viewed image.
“The results clarified the relationship between brain activities when people look at images versus when they imagine them,” senior author Takufumi Yanagisawa added.
“The electrocorticogram readouts of the imagined images were distinct from those provoked by the actual images viewed by the patients. They could also be modified to be even more distinct when the patients received real-time feedback.”
The time it took to distinguish the viewed and imagined images differed when participants pictured a word or a landscape, perhaps due to the different areas of the brain where these two things are imagined.
The new breakthrough brings the possibility of mind-reading, or at least mind’s eye reading, a little closer. For the vast majority of people who have the ability to picture things in their minds, at least. Around 2 percent of people are aphantasic, which means they lack the ability to do so. (And if that blows your mind, there are people who have no internal monologue either.)
The technology could, the authors hope, be developed as a communication device for people with paralysis. For sufferers of amyotrophic lateral sclerosis (ALS), who rely on communication devices that require some motor control to function, for example, this could be a game-changer.
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