Imagine if we could create a new pattern of activity in a person’s brain that enables faster learning or improves the treatment of psychiatric and developmental disorders such as depression or autism. Now, a picture can achieve this without brain surgery or physical manipulation. Does that sound like science fiction?
It still holds. Coraline Iordan, an assistant professor of brain and cognitive sciences and neuroscience at the University of Rochester, has made significant strides in demonstrating that learning new visual categories of objects is possible. This marks the first time such an achievement has been shown.
Learning typically occurs when our brains change due to experience, study, or instruction. However, Iordan and his colleagues at Yale and Princeton have successfully tested a novel approach to teaching the brain to learn through external manipulation and neural feedback, which they call “sculpting” brain activity patterns.
“Our method allows us not only to influence complex patterns in the brain by guiding them toward known patterns but also—for the first time—to insert a new pattern into the brain directly. We can then measure the effects this has on a person’s behaviour,” says lead author Iordan.
Brain sculpting—a new approach to learning?
The scientists employed real-time neuroimaging and second-by-second neurofeedback to alter how the brain represents and processes information about visual objects. In a functional magnetic resonance imaging (fMRI) machine, study participants viewed objects projected onto a mirror above their heads resembling a small screen. The object—an abstract shape that some participants interpreted as a petal, plant bulb, or butterfly—pulsed gently on the mirror until participants learned to “move” it by using their thoughts. This movement was based on a specific pattern of brain activity, which the scientists had chosen in advance and was monitored via fMRI in real-time. The researchers instructed participants to “generate a mental state” that would reduce the shape’s oscillation, but they did not teach the participants how to achieve this mental state.
“One of the study’s notable findings is that neural responses and related behaviours to new categories happened without explicit awareness of those categories. This demonstrates that a long-standing tradition in psychology regarding implicit processing—defined as the capacity to respond meaningfully to information without conscious awareness—also applies to the learning and forming new neural representations,” says coauthor Jonathan Cohen, a cognitive neuroscientist at Princeton University.
The immediate feedback provided to the study participants allowed them to stop the wobbling image in the mirror once they successfully altered their representation of a visual object to align more closely with a brain activity pattern designated by the researchers. This approach did not involve directly teaching participants what the categories of visual objects were; instead, the scientists developed a method that changed how participants’ brains processed and represented the individual objects within those categories. Essentially, they facilitated the learning of new object categories by modifying the participants’ brain activity.
“Instead of teaching you something and measuring how your brain changes, we wrote a new category into your brain that would have appeared had you learned it yourself,” explains Iordan. “Then we tested whether you saw the new category that we had inserted. Turns out you did.”
To ensure study participants were highly motivated to succeed, they were rewarded monetarily if they managed to stop the image wobble, which over six daily sessions could amount to a sizeable bonus.
Future applications
Scientists are working to better understand what exactly happens to brain function in people with a variety of neuropsychiatric, developmental, or psychological disorders, such as major depression, visual agnosias (the inability to recognize everyday items), and autism. According to Iordan, a method like theirs may eventually play a role in clinical treatment by modifying the brain patterns of patients to make theirs look more similar to the brain patterns found in the neurotypical population, which down the road could lead to new approaches for treatment, either by itself or in conjunction with already existing therapies.
“This study is one of the most powerful demonstrations yet of brain training with real-time fMRI. Dr. Iordan used neurofeedback to help humans create a category in their mind that then influenced their behavior,” says coauthor Nicholas Turk-Browne, a psychologist at Yale University. “In the future, this discovery could inform the development of brain-computer interfaces and clinical interventions.”
At its core lies the scientists’ ability to access the brain in a way that hasn’t been done before.
“We essentially turned learning on its head and taught your brain something that caused you to vicariously gain information, even though you were never explicitly given that information,” says Iordan. “That tells us we have access to the building blocks of learning in the brain in a way that we haven’t had before—for learning things that are much more complicated, such as entire categories of items, complex visual things, or potentially even beyond that someday.