A long−known symptom of depression is that sufferers no longer derive pleasure from the everyday activities that used to make them happy. Now researchers are able to see the changes in the brain, via functional Magnetic Resonance Imaging (fMRI), that accompany this phenomenon. The findings come from the Lawson Health Research Institute in Ontario.
While patients were listening to their choices, both favorite and neutral, the researchers scanned their brains with fMRI.
Elizabeth Osuch and her team had 16 patients recently diagnosed with major depression and 15 non−depressed participants listen to their favorite music as well as music for which they had no strong liking or disliking (the participants had made lists of their musical selections for the researchers beforehand). While patients were listening to their choices, both favorite and neutral, the researchers scanned their brains with fMRI. This technique measures changes in local oxygen consumption in the brain, thereby signaling which structures are active and which are not.
In the depressed patients, the researchers saw considerably less activity in the parts of the brain that are known to be associated with pleasure and reward processing than they saw in the control group. Osuch says that her “results revealed significant responses within the areas of the brain that are associated with reward processing in healthy individuals. They also showed significant deficits in these neurophysiological responses in recently depressed subjects compared to the healthy subjects."