It’s often called the mind’s eye. You look at something in the real world, then—after your eyes close—you can still picture it.
In a new study, Misryoum newsroom reported that imagined and perceived objects appear to activate the same neurons and use the same neural code. The work, described in the journal Science, focused on what was happening inside the ventral temporal cortex, a region tied to recognizing objects. Misryoum editorial desk noted that this goes beyond what brain scans can usually reveal, because tools like functional MRI don’t track the behavior of individual neurons.
“About 40% of those neurons reactivated when you were imagining the object,” said Varun Wadia, a brain scientist at Cedars-Sinai Medical Center and the California Institute of Technology. He was describing something that sounds almost too neat: when participants imagined specific items they had previously seen, a substantial fraction of the same cells that responded during real viewing lit up again. And—this is the part researchers seemed to care about—those neurons reactivated with roughly equal strength.
The experiments came from studying 16 patients with epilepsy. They were already in the hospital and already had electrodes implanted to help doctors locate the source of their seizures. That setup let Wadia and collaborators monitor the activity of more than 700 individual neurons in each participant while people watched images on a computer screen. Misryoum analysis indicates the team could then decode what “code” these cells used to convey visual information. Participants saw hundreds of images spanning broad categories—faces, animals, plants, and words—plus small objects such as sunglasses and water bottles.
Then came the imagination part. In a second phase, each participant closed their eyes and imagined one of the objects they’d seen earlier. While they did, the researchers tracked the same neurons that had been active during perception. Kalanit Grill-Spector, a psychology professor at Stanford University’s Wu Tsai Neurosciences Institute, said in an interview that this “has not been demonstrated before at the neural level.” You can almost feel the quietness of a lab at that moment—no bright stimulus on the screen, just someone picturing an airplane or a bottle somewhere behind their closed eyelids.
Because the overlap between perception and imagination was so strong, Misryoum newsroom reported that the team could tell which object a participant was imagining, including details about it—“like it’s so big and it’s at this angle, and it’s outside or inside,” Ueli Rutishauser explained. Rutishauser, whose lab at Cedars-Sinai carried out much of the work and who is also on the faculty at Caltech, emphasized how specific the reactivated patterns could be.
The findings also connect to a bigger, older idea: the brain might reuse parts of its visual system to “fill in” what isn’t currently in view. Thomas Naselaris, a neuroscientist at the University of Minnesota, said objects are three-dimensional and present themselves one side at a time, yet people intuitively model the parts they don’t see—like imagining the bumper on the back of a car. Visual imagination, he added, also lets people recombine familiar parts into unfamiliar configurations, like a unicorn.
There’s still a gap, though. Misryoum editorial team stated the research does not explain what happens in people with aphantasia, a condition that leaves them unable to voluntarily summon mental images. Rutishauser said he learned about the condition after giving a talk on imagination at a scientific meeting—afterward, a prominent and successful scientist told him, “I don’t know what you’re talking about. I don’t see anything when I close my eyes.” Scientists believe these individuals rely on words or concepts instead of images, but understanding how their neurons achieve that will require studies directly examining their brain activity. For now, the new data at least tighten the link between seeing and imagining—suggesting the same neural machinery might be doing double duty, even if the brain is working with a blank screen.
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