Emotional-motivational responses in subclinical bipolar disorder

Abstract

This study tested two general hypotheses concerning emotional-motivational responses by individuals with subclinical bipolar disorder. The "intensity hypothesis" stated that bipolar individuals have more intense emotional-motivational responses in general than normal individuals. The "quality hypothesis" stated that bipolar individuals have qualitatively different emotional-motivational responses to certain situations than normal individuals. The theory and research leading to these hypotheses was reviewed within Staats' paradigmatic-behaviorist frame of reference. Two major grounds for the hypotheses were: (a) The paradigmatic model of psychopathology has implied the involvement of emotional-motivational basic behavioral repertoires in the etiology of bipolar disorder. (b) There is indirect evidence that bipolar symptoms are responsive to psychosocial stimulus conditions, which is in keeping with the notion that psychosocial stimuli produce different emotional responses among bipolar individuals than among normal individuals. The design of the study involved the administration of the General Behavior Inventory (GBI), Pleasant Events Schedule (PES), and Unpleasant Events Schedule (DES) to 240 undergraduate student volunteers. Using GBI cut-off scores subjects were classified as "bipolar" or "noncase." Eleven bipolar and 19 noncase subjects were available for individual testing of their emotional responses to the positive mood form of the Velten Mood Induction Procedure. Subjects' pre- and posttreatment mood was assessed in terms of a writing speed task, the Multiple Affect Adjective Check List (MAACL), the Profile of Mood States (POMS), skin temperature, and skin conductance. The primary group comparison statistics yielded null results. However, subsequent exploratory analyses yielded findings that were compatible with the intensity hypothesis. Among the results from the exploratory analyses were a significant canonical correlation between the GBI mood symptoms and the intensity levels of the PES and DES item ratings. Also, a stepwise discriminant analysis procedure showed that bipolar individuals rated significantly less UES items as "moderately unpleasant" than noncase subjects. No significant group differences in response to the Velten Mood Induction Procedure were detected. The results were discussed in terms of their implications for theory, treatment, and future research.