Ask A Scientist: Can Brain Scanners 'See' a Kid's Imagination at Work?
Dr. John S. Hutton, pediatrician and clinical research fellow at Cincinnati Children's Hospital, is the lead author of a recent study that pinpointed the part of the brain that helps young children visualize stories grown-ups read to them. Essentially, Hutton and his team have found a way to "see" kids' imaginations at work.
Perhaps not surprisingly, children who are read to often at home and who have many books in their homes are better at visualizing what they're hearing. And that's important, Hutton said, because the part of their brains they are using for that task is the same one older people use to picture what they are reading.
Social scientists have long touted the importance of reading with young children, and brain scientists have previously shown its importance to cognitive development generally. But Hutton's study is one of the first to prove the theory with actual brain imaging from an fMRI scan. Nineteen children were able to stay still enough to produce valid readings for this study, which is actually a solid sample size for a study of this kind, said Hutton.
Hutton recently explained the study in greater detail to us. The conversation below has been edited for clarity and length.
So what exactly happened during this experiment? And what were you trying to figure out?
We sampled a group of preschool children, ages 3 to 5, intended to represent the general population variety of racial and socioeconomic backgrounds. We had them all undergo functional magnetic resonance imaging, or FMRI. In the scanner, we used what's called a story listening task. For alternating one-minute blocks, the child heard a simple age-appropriate story and then just plain, speech-like tones. We want to be able to look at the activation of the brain during the story and subtract off the activation that comes from hearing the sound. What's left is the activation in the brain that's specifically related to the child processing the story that they're hearing.
Interesting. You basically found a way to see what happens in a child's brain is when he hears a story that goes beyond what would happen just from processing language. And what were your findings?
[We saw activity in] specific parts of the brain that involve processing—processing words in the temporal lobes, understanding in some other areas. Then actually quite a bit of the activation is in visual parts of the brain that are called visual association areas.
The kids in the scanner weren't seeing any pictures; they were just hearing. So all the visual areas that lit up were interpreted as reflecting their imagination as they were imagining what they're hearing.
From there, we asked families a series of questions about the home environment and the child's exposure in three different categories. One was everyday conversation; one was learning a specific skill; and the other was all about reading. We applied the scores in each of these scales to the brain-imaging results, and that basically caused us see a physical association between the scores on the surveys and how kids' brains light up in the scanner.
What we found was that only the reading subscale was significantly associated with activation of the brain during the story-listening task.
So you found that kids who read more at home had more brain activation when they were read a story?
Yeah. Basically, it was there was a specific part of the brain that lit up more for kids who had higher levels of shared reading at home with their parents, a greater frequency of reading, a higher number of books in the home and who were read a greater variety of books. Those kids seemed to activate this one particular part of the brain more significantly than kids that had less reading exposure at home.
The parts of the brain specifically related to the reading environment was an area called the parietal-temporal-occipital or PTO association cortex. That's on the left side, kind of in the back. And it's a part of the brain that's involved with integrating a multisensory affirmation. It helps the brain process words that are heard with visual images.
Here there are imaginary visual images and [the PTO association cortex] puts it all together to understand what it is that the child is hearing.
The way I describe it is that if child's hearing a story that says, "the frog jumps over the log," the visual part of their brain says, "OK, I know what a frog looks like. I know what a log looks like. Let's put it all together." And then they get a mental picture.
Later, this part of the brain is recruited for reading once kids actually learn to read [by themselves]. It's the part of the brain that, if you're reading a Harry Potter book, would help you imagine what Hogwarts looks like.
So it sounds like kids who have a lot of exposure to storytelling and reading at home are doing a particularly good job with picturing things in their "mind's eye," and that's beneficial because when they learn to read later it's the part of the brain they'll need to understand what they're reading.
Yeah. That's sort of the way we describe it. Kids with more practice flexing that muscle when they're little, hearing a lot of stories on their parents' lap, [will get stronger]. They develop this part of their brain that allows them to really bring these stories to life as they get older too.
Is this proof that it's important to read with your kids, then? Because a stronger brain muscle in this particular area is important both for language and for reading?
It's really the first brain imaging that's looked in there and tried to figure out what part of the brain is involved [in processing stories]. For years, people have said, "reading builds brains. Reading is good for your brain." And we're trying to point out that it's actually inside this one part of the brain. There's still a whole lot of work to be done on that, but it's an initial signal that, "yes, this is important." [Reading] is not just a nice thing to do with kids, it's really important for their brain development.
What's the biggest takeaway for teachers and parents from this research?
It reinforces the importance of developing a consistent ritual of shared reading. [It should be] something that becomes an important part of the day, a priority. Especially these days, it underscores the importance of that early analog experience. Just keep giving kids the opportunity to practice using their imagination and resisting videos. Reading on an iPad is fine as long as it's a static thing and not a bunch of cartoons jumping around. Old-fashioned story time is really an important practice for them.
Photos: 1. John S. Hutton 2. A 3D rendering of the brain's left hemisphere with a cut out showing the area of activation in the study (posterior, parietal-temporal-occipital association cortex).