The Journal of Neural Engineering described an experiment with 18 test subjects wearing a cap wired with EEG sensors.
When the drivers in the simulator thought about slamming on the brakes, the car did so automatically a fraction of a second more quickly than they could, ABC News reported Friday.
Brain waves told the car to hit the brakes an average of 130 milliseconds faster than the driver's foot did, the researchers said.
In the experiments, that translated into a car doing 62 mph needing 12-15 fewer feet to come to a stop.
"Waiting for the driver's response can lead to a slow response in emergency situations," said Stefan Haufe of the Berlin Institute of Technology.
"Therefore, in order to obtain a faster confirmation, our study suggests that it is feasible to detect a driver's intention to brake, which naturally precedes any observable actions."
The researchers said the technology is far from real-world applications at this point.
"The EEG system has to cope with a multitude of artifacts" -- random electronic noises -- "that are stronger than the neural signals," they said.