Reaction time and longevity.

Hagger-Johnson et al. note a correlation between reaction times (doing a button press as quickly as possible after a light flashes on a computer screen) and mortality in 5,145 adults ages 20 to 59 (measured in the late 1980s and early ’90s). The subjects were followed to see how many would be alive after 15 years. After controlling for smoking, drinking, and other factors, the authors found that those with slower reaction times (one standard deviation less than average) were 25 percent more likely to die of any cause, and 36 percent more likely to die of cardiovascular disease, than those with faster reactions. There was no correlation with cancer deaths. The reasons for the statistical correlation is not clear, but the obvious idea is that slower reaction times may reflect brain or nervous system problems that increase morbidity.