Anhedonia is the inability to experience pleasure and is one of the main symptoms of depression. A brain-scan study by researchers at the University of Wisconsin-Madison has been looking into the neuroscience of anhedonia. The researchers studied 46 people, 27 of whom had depression. The participants were shown positive and negative images and asked to think about them for a while to accentuate the emotions they produced. The areas of the brain associated with positive emotions were just as easily activated in the people with depression but they were unable to sustain the levels of activity in these areas over time, compared to the control group.
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