【31】, optical illusion can cut highway crashes. Japan is a case【32】. It has reduced automobile crashes on some roads【33】 nearly 75 percent using a simple optical illusion. Bent stripes, called chevrons【34】 the roads make drivers think that they are driving faster than they really are, and thus drivers slow down. Now the American Association Foundation for Traffic Safety in Washington D. C. is planning to【35】 Japan's success. Starting next year, the foundation will paint chevrons and other patterns of stripes on selected roads mound the country to test how well the patterns reduce highway crashes. Excessive speed plays a major role【36】 one fifth of all fatal traffic accidents, according to the foundation.【37】 those accidents, the foundation will conduct its tests in areas where speed-related hazards are【38】-- curves, exit slopes, traffic circles, and bridges. Some studies suggest that straight, horizontal bars painted across roads can initially【39】 the average speed of drivers in half【40】 , traffic often returns to full speed within, months as drivers become used to seeing the painted bar.
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