Researchers are increasingly using magnetic resonance imaging (MRI) scans to see which areas of the brain are associated with certain activities, thought processes and characteristics. Researchers at the University of Chicago used MRI scans to look at the links between brain activity and 'perceived social isolation,' i.e. loneliness. They tested 23 female undergraduates to find out how lonely they were. They then put the participants through an MRI scanner while showing them pictures. The lonely participants showed much less activity in a part of the brain called the ventral striatum (which is associated with rewards) when they looked at pictures of people in pleasant settings and much less activity in a region called the tempoparietal junction (which is associated with empathy) when they saw pictures of people in unpleasant settings. But it is unclear whether it is loneliness that affects brain structure or brain structure that makes it more likely that some people will be lonelier than others.
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