Great stuff. We could go a step further and change all the red traffic lights and brake lights to white. Because by the same logic, it takes wider range of the spectrum, so it would be easier to recognize. Let's do it overnight and don't tell anybody about it, that will really help.<br>Sure, we can ignore the years of evolution and social convention that taught us to associate red with blood and sharp tones with attention (microwave, bell on the church, etc); so both are used to indicate danger. Let's throw all that out and make the reverse beep a white noise. The same white noise that our brains learned to filter out in the city life. <br><br>And while we are at it, let's make the car horns do a white noise as well, at least it will piss the drivers off as well, so they will use it only when necessary, not when they are angry.<br><br>Sarcasm off.<br>Whoever did that "research" must have done it in some university lab, where the beep / white noise was the only sound. There it may be better to detect. But in city soundscape, we filter that out.