Vanderbilt scientists conducted an experiment to gauge whether work ethic can be determined by chemicals in the brain.
The study, which was published in Journal of Neuroscience, examined the brains of 25 young adults, ranging in age from 18 to 29.
The subjects were tested on a variety of topics and offered a monetary reward for successfully completing the tasks. The questions and tasks were scaled based on difficulty; the more complicated the questions, the higher the reward.
Researchers found that those who exhibited a higher willingness to work, or "go-getters," tend to release high levels of a chemical called dopamine in areas of the brain that are associated with motivation and reward.
Conversely, those who are tabbed as "slackers" had higher dopamine levels in areas of the brain that control emotion and risk perception.
"At this point, we don't have any data proving that this 20-minute snippet of behavior corresponds to an individual's long-term achievement," said Vanderbilt Professor of Psychology Davis Zald.
"But if it does measure a trait variable such as an individual's willingness to expend effort to obtain long-term goals, it will be extremely valuable."
Further research is needed to examine whether dopamine levels also explain altered motivation seen in mental illnesses such as depression and addiction.