Car safety studies don’t get much stranger than this.

The latest crash test results from the Institute for Highway Safety show that cars are safer than ever thanks to modern technology. Out of the 2021 model-year cars that were crash-tested last month, 49 earned the highest Top Safety Pick+ award. We’re used to seeing the IIHS testing cars to destruction, but now the organization has conducted an unusual safety experiment to test how Level 2 semi-autonomous driver technology such as Tesla’s Autopilot and GM’s Super Cruise can affect a driver’s awareness of their surroundings.

Level 2 systems can control acceleration, braking, steering, and speed in certain scenarios, but they still require the driver to be alert and intervene if necessary. With the technology taking over control of the car, some drivers find it harder to focus on the road and become complacent with the technology, which has resulted in several fatal crashes.

Insurance Institute for Highway Safety

2019-2021 Mercedes-Benz C-Class Sedan Front View DrivingMercedes-Benz

To put this to the test, the IIHS strapped a giant stuffed teddy bear dressed in a high-visibility jacket to the back of a car and compared the reactions of three different groups of drivers to see if they noticed it drive past. Car safety studies don’t get much stranger than this.

“There are a number of laboratory methods for measuring situational awareness, but they don’t work so well on the road,” IIHS Research Scientist Alexandra Mueller explained. “The giant teddy bear on the back of the vehicle helps give us an objective measure of the driver’s focus that’s relevant to driving and doesn’t interfere with how that person normally drives.”

2019-2021 Mercedes-Benz C-Class Sedan Rear Angle ViewMercedes-Benz

2019-2021 Mercedes-Benz C-Class Sedan Side ViewMercedes-Benz

To test how attentive they were when using semi-autonomous tech, 31 people drove a 2019 Mercedes-Benz C300 for around an hour on a stretch of highway. One set of drivers who regularly use Level 2 drove with the semi-autonomous driving assist switched on. Another set of drivers who had little to no experience with these driver assists also drove with it switched on, while another who was also unfamiliar with the technology drove the Mercedes with the tech turned off.

During the journey, a car with the pink teddy strapped to the back overtook each driver three times and stayed in front for around 30 seconds. Cameras then recorded the driver’s reaction. Each driver was then asked if they noticed anything unusual. If the answer was yes, they were asked how many times they saw the bear.

2019-2021 Mercedes-Benz C-Class Sedan DashboardMercedes-Benz

2019-2021 Mercedes-Benz C-Class Sedan Front SeatsMercedes-Benz

The IIHS found that over twice as many people in the experiment who don’t regularly use Level 2 autonomous tech failed to notice the bear. By contrast, nearly every driver who regularly uses the technology and had it switched on saw the bear. This group was also more likely to correctly identify how many times it appeared.

Of course, the test sample was very small so the study wasn’t conclusive, but the IIHS believes the results show that “partially automated driving systems have the potential to improve drivers’ situational awareness” once the driver becomes accustomed to the technology. Drivers less experienced with using autonomous technology, on the other hand, “may have more difficulty keeping track of what’s going on around them when using the unfamiliar technology.”

2019-2021 Mercedes-Benz C-Class Sedan Rear Perspective DrivingMercedes-Benz

2019-2021 Mercedes-Benz C-Class Sedan Driving Front AngleMercedes-Benz