People who have no motivation to work hard may have their brain to blame. A new study reported in the latest issue of the Journal of Neurosciences says, the way your brain handles dopamine may predict whether you are a hard worker or a slacker.
Dopamine is a neurotransmitter in the brain involved with movement, motivation, memory, processing emotions, and feeling pleasure or pain. Some diseases tied to dopamine dysfunction include Parkinson’s disease and schizophrenia.
Psychologist Michael Treadway, from Vanderbilt University in Nashville, who co-led the research, said “Past studies in rats have shown that dopamine is crucial for reward motivation. But this study provides new information about how dopamine determines individual differences in the behaviour of human reward-seekers.”
Researchers took 25 healthy men and women between the ages of 18 to 29 and asked them to complete button-pushing tasks for a monetary reward.
Some were difficult tasks while others were easy. For example, a hard task would require pushing a button 100 times in 21 seconds with a non-dominant pinky finger. An easy task was pushing a button 30 times in seven seconds, using a dominant index finger.
The rewards varied, from $1 for an easy task to over $4 for the hard tasks.
Researcher Michael Treadway, PhD, a clinical fellow at McLean Hospital and Harvard Medical School says, “If you look around at the people you know, yourself included, and think of the people always driven to work hard vs. the people who prefer to take it easy, what this study shows is that the range in motivation is in part due to how the dopamine system functions.”
Those who worked the hardest had higher levels of dopamine in the striatum and ventromedial prefrontal cortex areas of the brain, both known to be important in reward and motivation.
Treadway found that those not willing to work hard for the money reward had high levels of dopamine in the insula part of the brain which is involved in emotion and risk perception.
Michael Treadway, PhD says, “The folks with relatively more striatal dopamine were focused on the reward. The folks with more insular dopamine were thinking about how tired their pinky was. They were focused on the costs.”
Why is this study so important? Study leader Professor David Zald, also from Vanderbilt University said, “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. With objective measures we could treat the underlying conditions instead of the symptoms.”