Why are some car accidents caused by drivers who say they didn’t “see” an oncoming pedestrian, motorcyclist, or bike rider? There have been many roadside fights consisting of “I was right there in front of you, how could you not see?!” and many bewildered drivers answering apologetically that they didn’t see the obstacle in their path. It turns out that those drivers who claim they didn’t see the obstacle were not just failing to pay close enough attention to their surroundings while driving—new research has explained a “look but fail to see” phenomenon that occurs in our brains.
In a recent publication last week, researchers investigated what happens in the brains of drivers who are involved in “look but fail to see” (LBFTS) accidents. There are some psychological factors which can keep people from seeing obstacles at road junctions, such as inattentional blindness and change blindness. However, the team of researchers measured drivers’ eye movements and tested how well the drivers were able to report vehicles that were approaching in a driving simulator. The researchers noted that there was often a complete failure to report that the drivers saw approaching vehicles, particularly motorcycles.
This led researchers to investigate how memories are connected to the failure to see obstacles. They concluded that it isn’t that the drivers don’t actually see the obstacle or that their brain doesn’t register that there is an obstacle—but that the brain is forgetting about the obstacle after having seen it. In fact, drivers in the study failed to remember that there was an oncoming obstacle around 13-18% of the time.
The leading author of the study from the University of Nottingham, Peter Chapman, Ph.D., believes that our brains are overloaded with too much information to process visually when driving. Chapman believes that you may see the obstacle, but if you look at something else after you have seen the obstacle (such as double checking the traffic again), your brain’s short-term memory will fill up with new images, and it makes recalling the initial obstacle extremely difficult.
We’re not saying to stop double-checking traffic after you see an obstacle, but to be aware that this occurs. After you see the obstacle and look at something else, this “subsequent visual search” (which precedes the action to pull into the junction/intersection in your vehicle) will overload your memory with new information.
Chapman has offered a trick to help your brain remember that you have seen the obstacle. Naming the obstacle out loud when you first see it, such as “bike,” “motorcycle,” or “walker,” can place the visual information into your phonological short-term memory. This will help you remember, and hopefully reduce the number of “look but fail to see” accidents—which account for approximately 100,000 deaths per year internationally.
- Robbins CJ, Allen HA, Miller KA, Chapman P (2019) The ‘Saw but Forgot’ error: A role for short-term memory failures in understanding junction crashes? PLoS ONE 14(9): e0222905. https://doi.org/10.1371/journal.pone.0222905