According to the May 1, 2012 EurekAlert article Differences in dopamine may determine how hard people work, 'The study found that people who chose to put in more effort '” even in the face of long odds '” showed greater dopamine response in the striatum and ventromedial prefrontal cortex, areas of the brain important in reward and motivation.'
And, 'In contrast, those who were least likely to expend effort showed increased dopamine response in the insula, a brain region involved in perception, social behavior, and self-awareness.'
Their research paper will be published in the May 2, 2012 issue of The Journal of Neuroscience.
Within their experiment, Treadway and Zald asked human participants to press a button in order to earn various amounts of money. They had to press the button more rapidly to earn more money.
The participants decided how rapidly to press the button but the faster they pressed it the more money they won.
Some were motivated to various degrees, some less and others more.
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