Study looks at cloudy judgment of smokers

A defining feature of smoking addiction is that smokers pursue their habit even when it's clear they are forgoing other benefits, such as good health. Now, brain scans suggest that this dodgy decision-making may extend into other areas of their lives.

Pearl Chiu and her colleagues at the Baylor College of Medicine in Houston, Texas, studied 31 chronic smokers and 31 nonsmokers as they played a game inside an fMRI scanner.

The players had to invest money in a simulated stock market over several rounds. After each round, they were given feedback on the returns from their investment choices, including how they might have earned more had they invested differently.

While nonsmokers generally used this feedback to shape future rounds of investment, the smokers' behavior was barely affected. Brain scans revealed that they were processing the information but, unlike the nonsmokers, they could not seem to act on it to alter their performance (Nature Neuroscience).

The finding may help researchers hone in on brain differences in people who are prone to addiction.