Question: We often describe our emotional reaction to social rejection as "pain." A clever study asked whether social rejection causes activity in areas of the brain that are known to be activated by physical pain. If it does, we really do experience social and physical pain in similar ways. Subjects were first included and the deliberately excluded from a social activity while increases in blood flow i their brains were measured. After each activity, the subjects filled out questionnaires that assessed how excluded they felt.

Here are data for 13 subjects. The explanatory variable is "social distress" measured by each subject's questionnaire score after exclusion relative to the score after inclusion. (So values greater than I show the degree of distress caused by exclusion). The response variable is activity in the anterior cortex, a region of the brain that is activated by physical pain.

Plot brain activity against social distress. Describe the direction, form, and strength of the relationship, as well as any outliers. Do the data suggest the brain activity in the "pain" region really is directly related to the distress iron social exclusion?