“Early on in my career, I saw a lot of motor vehicle crashes, kids being ejected from cars, a lot of young people seriously injured and too many killed,” he recalls. But beyond the tragedy, Vaca also saw an opportunity for prevention. His experience motivated him to pursue research in injury prevention and public health, with a focus on driving and young people.
The son of a nurse and auto mechanic, Vaca has come full circle as a professor of emergency medicine specializing in safety and injury research. In his work at Yale School of Medicine, he combines his knowledge of risk factors for motor vehicle crashes with research on adolescent development and behavior. To tackle the growing problem of fatal crashes, Vaca has collaborated with colleagues at the Yale Child Study Center to establish an innovative research lab: the Developmental Neurocognitive Driving Simulation Research Center, or the DrivSim Lab.
Housed in the Department of Emergency Medicine at Yale, the DrivSim Lab applies expertise in crash injury and prevention, adolescent psychology, and brain science to the study of crash risk among teens and young adult drivers. “The mission of the lab is to understand behavior, brain development, and how the brain functions for adolescents and young adults as they learn to drive,” he says. The end-goal: to curb the number of injury crashes among the young and to make them safer drivers sooner.
Driving and the developing brain
Last year was one of the deadliest for fatal car crashes in the United States according to the National Safety Council, with a 6% rise in deaths over 2015. Teens and young adults are the most at risk, says Vaca, in part because their brains are still developing when they start learning to drive. Brain development, which continues into the mid-20s, tends to lag behind the complex demands facing novice drivers, he explains.
Vaca’s partners at the Child Study Center, including its chair Dr. Linda Mayes, agree. “The part of the brain involved in reward processing and reacting to emotions and stress — the part that makes decisions to go after something that is highly satisfying or salient without thinking about it — develops earlier than the prefrontal cortex in adolescents,” says Mayes. This misalignment in the parts of the brain that seek reward and weigh consequences is a key part of what sets young drivers apart from more seasoned ones, she notes.
It’s like the perfect storm, the researchers say: Teens and young adults who might not hesitate to take a risk engaging in one of the riskiest activities of all: driving.
“When you have a young novice driver, crash rates for the first year are twice that of experienced drivers,” says Vaca. Yet, they do eventually develop better driving skills. “The really fascinating thing is learning clearly occurs very rapidly over the first 6 to 10 months. Even in the first few months, you see crash rates steadily come down.”
But the science has not yet uncovered what exactly new drivers are learning to make them safer drivers and how to speed up that process, Vaca said. One goal of his lab is to use their research findings to shrink the window of time it takes for a teen or young adult to drive more safely.
The science of driving
In the DrivSim lab, a 19-year-old student volunteer hops in the half-car simulator and maneuvers down a virtual rural road — a two-lane byway dotted with an occasional traffic sign as well as other vehicles moving in either direction. After a few minutes, a car suddenly enters the scene from the right. The driver quickly veers out of the way before pulling over at the end of the simulation. He knew the vehicle would be coming because he’s done the simulation before, but another young driver might not have been so lucky, says Vaca.
The rural drive is one of many simulations the DrivSim lab can create. Hooked up to a software program, the half-car simulator is situated in front of a high-fidelity screen where researchers can project challenging and even dangerous driving scenarios for the teen to navigate, all in a safe research environment. Volunteer drivers wear an EEG net on their heads to record brain activity, as well as eye-tracking glasses to follow their gaze. The vehicle has all of the features of a real car — ignition, gear shift, steering wheel, signals, pedals, and mirrors. Additionally, it’s equipped with video to capture a range of metrics and driving behavior.
Unlike other driving simulation labs at research institutions across the country, DrivSim captures data about the brain while driving. “It’s not just a lab to study driving; it’s a lab to unpack cognition,” said Michael Crowley, assistant professor at the Child Study Center. The lab will initially focus on collecting and analyzing data in order describe how the young driver responds to different challenges.
For example, in one experiment, as volunteers are navigating a simulated road, the researchers will use sound, emitted in one ear, to mimic the distraction of taking a phone call. “By using sounds to one ear or the other, we can have a very precise event that draws your attention away from the roadway,” said Crowley. “We can look at the impact of distracted attention on your driving.”
The listening test can tell researchers how much input a driver can absorb before their driving becomes affected. On a more basic level, it will show them what areas of the brain “light up” in response to noises. With this information, Vaca and his colleagues can begin to describe how the developing brain, including brain regions that are not fully understood, responds and how these responses change over the time the teen learns to become a safe driver.
“Our focus is trying to understand these brain areas that are not characterized from a research perspective in a driving context, and then apply that knowledge to the development of programs that could help train youth to become better drivers sooner,” he explains.
Building a better driver
Another focus for the DrivSim Lab is the influence of peers. For example, research has indicated that if a young male driver is accompanied by another male passenger, the risk of a fatal crash rises. But if a woman sits in the passenger seat, the risk goes down. “Young males have greater risk than young females. They are wired differently in the brain. We need to understand that at the level of the brain, characterize it, and put it to use for prevention,” Vaca notes.
With the insights they acquire, the researchers can begin to inform and develop training programs to help young drivers improve their skills. “Imagine you’re driving and doing the listening test,” says Crowley, “and because you’re not a facile driver, it takes a lot of your brain resources to do both. That would indicate you need more practice. It could indicate that there is something about your attention that puts you more at risk. Maybe we would devise training that would train that aspect of your driving behavior.”
Vaca envisions training programs that young people could access online. Unlike many existing driver education programs, such training would be based on the science DrivSim develops and also be appropriate according to developmental stage. “Most driving training assumes one size fits all,” says Mayes. “It’s not developmentally driven.” The lab’s contribution to science and to the community is both the developmental approach to driving training and the evidence-based approach to analyze the impact of that training, she notes.
To meet that goal, the DrivSim Lab researchers are in the process of recruiting adolescents and young adults of driving age from the New Haven community to be test drivers. They are also partnering with other academic institutions, including UMass Amherst, MIT, and Harvard on a collaborative grant to apply their collective resources to a range of different driving research projects.
A frequent contributing expert to news stories about driving safety, Vaca would like the DrivSim Lab to also become a resource for the community, including youth, parents, educators, and policymakers. While the researchers run pilot simulations and recruit for studies, a website has been set up to disseminate breaking news about driving and safety.
“We believe that it’s really important because it’s such a key issue for the health and well-being of young people,” says Vaca. “They’re our future. We want to keep them safe, and that keeps the roadways safe for all of us.”
Source : Yale University