The Eyes Have It
The eyes are the windows to the soul, so the saying goes, but in Professor George Spilich’s cognitive neuroscience seminar, they’re providing insight into an equally mysterious and elusive place—the brain. You start to see how in what’s called the eye-gaze lab, where Erika Duenas ’14 positions her classmate Colleen Bancroft ’15 just so in front of a computer monitor. Mounted at its base is what looks like the business end of a pair of binoculars. It’s actually a specialized camera that’s recording every flicker of Bancroft’s eyes.
Duenas types in a few commands, and the monitor comes alive with a quickly blinking image of a military plane on a tarmac surrounded by disembarking soldiers. Somewhere in the image, something big is vanishing in one frame and reappearing in the next, over and over.
“Tell me when you see the change,” Duenas says, clipboard in hand. For 45 seconds the image blinks, while an infrared beam scans Bancroft’s eyes 60 times per second as they dart around the screen. Duenas times how long it takes Bancroft to say, “Oh, got it! It’s the turbine,” which is, indeed, disappearing and reappearing. Once you see it, you can’t believe it would be so hard to miss.
But for people who’ve suffered traumatic brain injuries (TBIs, or concussions), it can be easy to miss. “How can your brain take that big object that’s moving back and forth and just gate it out?” Spilich asks. “What we’re finding is that concussed people just have a harder time seeing these.”
Spilich, his colleague, Department Chair Lauren Littlefield ’91, and their students study the biology of mind and consciousness. This includes behavioral neuroscience, as well as the behavior behind consciousness, like memory, speech, and reading. The department’s three-year study of TBI’s long-term effects on cognitive functions, using about 150 student volunteers who’ve suffered concussions through various accidents, has yielded one of the largest data sets of its type in the country, Spilich says.
Research and real-world experience are at the center of the curriculum; hence, students get to use technology like the eye-gaze lab as they study how the brain works. Duenas’ research examines “change blindness,” a measure of how your brain distributes its resources to decide what bears notice and what doesn’t. She tested 40 volunteers who have had multiple TBIs (she herself has had four concussions in about five years, mostly through playing sports). She’s finding that the brains of people who’ve suffered multiple TBIs have a harder time finding the change in the images, which could have a bearing, for instance, on their reactions behind the wheel of a car.
Meantime, Bancroft, Jenna Schmaljohn ’13, and Natasha Berryman ’14 are using a protocol developed to test elderly people’s acuity while driving to help determine whether people with multiple TBIs have similar visual perception and peripheral vision issues. Both of these projects, Spilich says, are yielding intriguing results that the students will help present at a professional conference in the spring—a feather in their academic caps as well as on their resumes.
“The kids get hands-on. They use the equipment, they do the projects. You can’t learn to play baseball by watching the game,” he says, “can you?”