This paper introduces a picture system that can be used in functional imaging experiments exploring interpersonal relations. This is important for psychotherapy research to understand the neural basis of psychological treatment effects. Pictures have many advantages for the design of functional imaging experiments, but no picture system illustrating interpersonal behavior patterns is, to date, available. We therefore developed, on the basis of a validated card-sorting test, the Interpersonal Relations Picture System. In summary, 43 pictures with 2 or more stick figures in different social situations and 9 control pictures were composed. To test the relation between each picture and the appropriate description, two successive online surveys, including 1058 and 675 individuals respectively, were conducted. Using two question types, the grade expressiveness of each picture was assessed. In total, 24 pictures and 6 control pictures met our criteria for sufficient strength and consistency with the appropriate description. Both measures are correlated with each other in all pictures illustrating interpersonal behavior, but not in the control pictures. Relations to other stimulus types and the applicability of the new picture system in functional neuroimaging methods are discussed. It is concluded that the new system will be helpful in studying the profound effect of relational change in psychotherapy.
Keywords: Interpersonal relationships; neuroimaging; picture system; psychotherapy research; social neuroscience.