Alloy and Abramson: Demystifying Bipolar Disorder

Lauren B. Alloy delivers her James
McKeen Cattell Fellow Award Address.

It was standing room only as Lauren B. Alloy of Temple University delivered her James McKeen Cattell Fellow Award Address (unfortunately, award co-recipient Lyn Abramson of the University of Wisconsin-Madison was not able to be there). Her talk began with an overview of bipolar disorder (including the statistics that 4.4 percent of adults have a form of bipolar disorder at some point in their lives and that it is the 6th leading cause of disability worldwide) and the observation that “Bipolar disorder is at the same time both puzzling and fascinating to researchers and lay people alike because of the extreme contrast in mood and behavior that occur in the same individual.” Alloy also noted that although bipolar disorder results in severe problems in work performance and often leads to substance abuse, bipolar disorder is also associated with high achievement and creativity.

The focus of Alloy and Abramson’s research has been the ways in which the Behavioral Approach System (BAS) may help answer questions about bipolar disorder and provide some insight into the disease. The BAS normally regulates motivation and goal-directed behavior to attain rewards and avoid punishment. This system involves dopaminergic projections from the ventral tegmental area to a variety of reward-associated regions (such as the amygdala, ventral striatum, and prefrontal cortex).

Alloy and Abramson have suggested vulnerability to bipolar disorder may be related to an overly sensitive BAS. A hypersensitive BAS can lead to excessive BAS activation (in response to events involving rewards) or excessive BAS deactivation (in response to negative events). Too much BAS activation then results in excessive emotions and behaviors in the presence of goal relevant cues. These excessive behaviors are reflected in manic and hypomanic symptoms, including inflated self-esteem, euphoria, and racing thoughts. Conversely, excessive BAS deactivation leads to depressive behavior, including low motivation, hopelessness, and sadness.

Alloy presented data gathered in conjunction with the Longitudinal Investigation of Bipolar Spectrum (LIBS) Project, which involved screening 20,000 college students for potential bipolar spectrum disorders. The students completed a variety of assessments, designed to measure sensitivity of their BAS along with manic and depressive symptoms, and then underwent follow-up interviews. Among bipolar participants, higher BAS sensitivity predicted shorter time to onset of the next hypomanic/manic episode more so than lower BAS sensitivity. Interestingly, a number of participants in the LIBS study had symptoms that progressed, including 16.6 percent of Bipolar II participants progressing to Bipolar I Disorder. “High BAS sensitivity predicts greater likelihood and faster time of onset of hypomanic/manic episodes and it predicts greater likelihood of progression,” Alloy stated.

Alloy and her colleagues also studied the effect of BAS-relevant life events (e.g., striving for a goal) on bipolar symptoms and episodes. To investigate this question, they examined students in the middle of a semester and during final exam time. Results showed that out of the bipolar group, 42 percent of students had an episode during the exam period. In addition, a separate study showed that both high BAS activating events (e.g., striving to reach a goal) and high BAS deactivating events (e.g., failure to meet goals) predicted bipolar episodes in high BAS sensitive individuals. These results indicate that BAS-relevant life events may be able to trigger bipolar episodes and symptoms.

In addition, Alloy described a study linking high BAS sensitivity with vulnerability for bipolar spectrum disorders. Teenage participants were identified as high-risk or low-risk for bipolar disorder based on high or moderate BAS sensitivity and had follow-up interviews conducted every six months. Participants in the high BAS group were more likely than those in the moderate BAS group to have had a prior history of bipolar spectrum disorders. Alloy noted that one of their most exciting findings was that “among individuals with no prior history of bipolar disorder, high BAS sensitivity predicted the development of bipolar spectrum disorders.”

Alloy concluded by mentioning important implications of this research: “It may be possible to identify adolescents at risk for bipolar spectrum disorders with self-report and  behavioral, cognitive, and neurophysiological indicators of BAS hypersensitivity and reactivity. And if so, one could intervene early with these at-risk adolescents to prevent the onset of bipolar spectrum disorder. Or if you can’t prevent the onset, at least improve the course of an impending bipolar spectrum disorder.”