Slacker or go-getter – how hard you’re willing to work is strongly influenced by the chemistry in three specific areas of the brain say researchers in America.
A new brain imaging study using the mapping technique positron emission tomography has found that go-getters who are willing to work hard for rewards had higher levels of dopamine in the striatum and ventromedial prefrontal cortex – areas important in reward and motivation.
Conversely, slackers who are less willing to work hard had high dopamine levels in another area of the brain that plays a role in emotion and risk perception – the anterior insula.
“Past studies in rats have shown that dopamine is crucial for reward motivation, but this study provided new information about how dopamine determines individual differences in the behaviour of human reward-seekers,” said Michael Treadway from Vanderbilt University.
Dopamine’s role in the anterior insula came as a complete surprise and suggests more of the neurotransmitter in the area is associated with a reduced desire to work – even if it means earning less money.
Researchers took 25 healthy volunteers aged 18 to 25 and asked them to perform button-pushing tasks to determine their willingness to work for a monetary reward. First they selected an easy ($1 reward) or hard task (up to $4 reward), and were then told they had a high, medium or low chance of getting the reward. Tasks lasted 30 seconds, and participants were asked to perform them repeatedly for 20 minutes.
“At this point, we don’t have any data proving that this 20-minute snippet of behaviour corresponds to an individual’s long-tern achievement, 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,” said Professor of Psychology David Zald.
This research is part of a larger project searching form objective measures for depression and other psychological disorders where motivation is reduced – like attention-deficit disorder and schizophrenia.
“Imagine how valuable it would be if we had an objective test that could tell whether a patient was suffering from a deficit or abnormality in an underlying neural system,” said Zald. “With objective measures we could treat the underlying conditions instead of the symptoms.”