Brady Phelps


It takes two to be(come) multiple: An examination of the social contingencies contributing to the behaviors labeled as dissociative identity disorder.


Skinner (1974) stated “Complex contingencies of reinforcement create complex repertoires, and as we have seen, different contingencies create different persons in the same skin, of which so-called multiple personalities are only an extreme manifestation” (p. 171-172). Except for this reference, Skinner did not elaborate on the topic of “multiple personalities.” Arguments will be made that personality is behavior, and this behavioral repertoire could exhibit sufficient variability to be described as the display of multiple role enactments. DID can be conceptualized as overt behavior as well as complex verbal behavior, primarily in the sense of inappropriate tacting of one’s experiences, emotional responses and bodily states. But, as Skinner alluded, such behavior would result from complex contingencies. The behaviors of reporting to be different individuals, with different histories, and having differential abilities are likely operants resulting from atypical positive and negative reinforcement contingencies, as well as inappropriate rule-governances. These mechanisms control a repertoire that is reinforcing for both patient and therapist.


Dr. Brady J. Phelps taught undergraduate courses in behavior analysis at South Dakota State University for 29 years before retiring in May of 2021. Dr. Phelps conducted research in the areas of behavior analysis and basic behavioral neuroscience using an invertebrate animal model. Some of his most-read articles pertain to the topics of personality and self from a behavior analytic perspective. He is also one of the very few behavior analysts to address the behaviors of dissociative identity disorder or DID. Dr. Phelps has described himself as an avid consumer of as much of the literature pertaining to DID as he can stand to read.