Quick hand at Egyptian Rat Screw predicts long life

Longer Life, Reaction Time and IQ

According to the ancient Greeks, Zeus had 3 daughters who were known as the three Fates. One spun the thread of life, the second measured its length, and the third snipped it off. In our attempt to understand some of the rules of science, researchers have tried to offer a more plausible explanation for why some of us live longer than others. Researchers from the Universities of Edinburgh and Glasgow in Scotland have made a discovery even the Greeks couldn't have imagined - reaction time may be a core indicator of long life. They measured both the IQs and the reaction times of middle-aged subjects and conclude that both tests of mental ability were associated with life span, but reaction time was the stronger indicator.

These findings appear in Psychological Science, a journal of the American Psychological Society. This study builds upon earlier studies that show that individuals with lower IQs tend to die at younger ages than those with higher IQs. Investigators built upon this idea by adding what they define as a more fundamental measure of mental ability - efficiency in processing information. They believe that IQ tests might relate to physical health because people with higher IQs typically are more likely to be in occupations with safer environments. Reaction time is moderately related to IQ, but is a simpler assessment of the brain's information-processing ability - one that doesn't bear so much on other, possibly confounding factors like knowledge, education, or background.

They evaluted 412 male and 486 female 54- to 58-year-olds who took both an IQ test measuring their verbal and numeric cognitive abilities and a reaction-time test that measured how quickly they pressed a button after seeing a number on a screen. The researchers also recorded the participants' gender, employment, education, and smoking status. Over a 14 year period 185 participants died, and researchers compared their test results to see if the IQ or reaction-time responses predicted their mortality.

Results showed that those with higher IQ scores lived longer, a result consistent with other studies. The study also showed that characteristics significantly related to death included male gender and smoking. But they also found something new - faster reaction times seemed an even better predictor of long life than IQ.

There are different ways the results could be interpreted. Slow reaction times could reflect a degeneration of the brain, which in turn could reflect degenerating physical health (an obvious possible cause of earlier mortality). But in another study the IQs of 11-year-old subjects also were found to predict life span length, just as accurately as it did for the middle-aged participants in this 14-year study. Future studies of reaction times in younger-aged people may shed more light on the IQ-mortality connection.