Home > Public Resources > Trauma Blog > 2022 - July > Applying Behavioral Economics to Our Understanding of PTSD Applying Behavioral Economics to Our Understanding of PTSD Olin, McDevitt-Murphy, Murphy, Zakarian, Roache, Young-McCaughan, Litz, Keane, & Peterson July 1, 2022 As humans, we tend to seek and prefer simple explanations for our own behavior. Human behavior, however, rarely fits simple, linear patterns. If it did, many of us in psychological science would be out of a job. Behavioral economics is a metatheory that combines operant learning theory with microeconomics, and it is particularly helpful for theorizing about and explaining patterns of behavior that seem counterintuitive or complex (Kahneman, 2003). For example, reinforcer pathology is a concept within behavioral economics that has been used to describe why people persist in behavior patterns that do not appear to serve them (e.g., drug or alcohol use, unhealthy eating, etc.). It is theorized that this occurs because people overvalue or have an excessive preference for a “reinforcer” (e.g., drug, food, gambling) that is available immediately, despite having some potential for negative consequences in the long term (Bickel et al., 2014). These patterns share a key feature: the problem behavior’s reinforcement occurs immediately and its harmful or maladaptive consequences tend to be delayed in time. When there is also a shortage of competing rewards available in the environment, this increases the tendency to choose the immediately reinforcing activity. Posttraumatic stress disorder (PTSD) is another disorder that we often conceptualize behaviorally, framing avoidance and other trauma-related symptoms as the result of classical and operant conditioning (Keane & Kaloupek, 1982; Keane et al., 1985, Mowrer, 1960). In the present study, we examined whether avoidance among individuals with PTSD could be conceptualized within this behavioral economic reinforcer pathology framework as well. Avoidance is negatively reinforced by the relief experienced in the temporary reduction of arousal that occurs when one avoids a trigger. In the long term, however, this pattern can actually contribute to worsening PTSD severity. To assess this theory, we examined the relationships between PTSD severity and three behavioral economic constructs: delay discounting, future orientation, and reward availability. Delay discounting is the extent to which a person reduces (or discounts) the value of a reward based on when it will be available to them. For example, you might prefer to receive $75 now, compared to $100 a week from now, because the value you place on each sum of money is affected by the delay in receiving them. You discount the $100 based on the delay. The more you devalue the reward available later, the more “steeply” you discount that delayed reward (Mazur, 1987; Rachlin et al., 1991). We theorized that PTSD severity would be related to steeper discounting, corresponding to preference for the immediate relief of avoidance, as opposed to long term rewards that are eliminated by avoidance (e.g., social connections). A related construct, future orientation, reflects the extent to which people take into account the future consequences of their choices, versus focusing primarily on the here-and-now (Strathman et al., 1994). Due to the tendency for PTSD to result in a sense of foreshortened future (Haag et al., 2017), we anticipated that PTSD severity would be related to low future orientation. Reward availability refers to the accessibility of rewards in your environment, as well as your capacity to seek out and enjoy those rewards (Carvalho et al., 2011). Among those with PTSD, we predicted that over time, the preference for the immediate relief of avoidance would result in loss of access to and enjoyment of other rewards. We examined these relationships in a sample of 110 combat veterans and found that worse PTSD severity was significantly related to lower future orientation, fewer rewards available in participants’ environments, and less pleasure derived from rewards. Unexpectedly, though, it was not related to delay discounting. Also surprisingly, when examined by PTSD symptom cluster, avoidance was not the driving force behind these relationships. We draw from these findings that PTSD does appear to be related to over-valuing the present over the future (i.e., not taking future consequences into account in decision making). Perhaps more interestingly, though, the strongest relationships in our findings are those between PTSD severity and the lack of available rewards in one’s environment. We theorize that this may represent the narrowing of one’s world that occurs as a result of constant heightened arousal and intrusions, causing avoidance of an ever-expanding network of triggers over time. Imagine you have PTSD: as more and more of your world becomes triggering, you have to avoid more and more people, places, enjoyed activities. Over time, this narrowing makes the present feel even more appealing and the future feel less relevant, so you pick the immediate reward of less distress over the long-term reward of a fuller life. As such, PTSD appears to fit well within the framework of reinforcer pathology and behavioral economics. Target Article Olin, C.C., McDevitt-Murphy, M.E., Murphy, J.G., Zakarian, R.J., Roache, J.D., Young-McCaughan, S., Litz., B.T., Keane, T.M., & Peterson, A.L., for the Consortium to Alleviate PTSD (2022). The association between PTSD and delay discounting, future orientation, and reward availability: A behavioral economic model of PTSD. Journal of Traumatic Stress. Discussion Questions The present study focused on three constructs from the behavioral economics literature, but the literature on reinforcer pathology and behavioral economics is vast. What other constructs, methodological approaches, statistical examinations, etc. might allow further development of our understanding of PTSD from a behavioral economic perspective? How might this behavioral economic conceptualization of PTSD impact psychotherapy and psychotherapy research? Reinforcer pathology offers a transdiagnostic concept for understanding psychopathology from a behavioral perspective. It was originally applied to substance misuse and has since been applied to various other psychological disorders. How might we use this framework for understand comorbidity and the impact of comorbid disorders on individuals post-trauma? About the Authors Cecilia C. Olin, M.S., (she/her) is a doctoral student in The University of Memphis Clinical Psychology Program. Her research focuses on mechanisms of severity in PTSD, substance use disorders, and depression. She has a particular interest in transdiagnostic mechanisms and models of psychopathology, such as behavioral economics and reward functioning. She would like to extend this research to understanding mechanisms of treatment response. For more information, Cecilia can be contacted at [email protected]. Meghan E. McDevitt-Murphy, Ph.D., is a Professor of Psychology at The University of Memphis. Her research focuses primarily on PTSD and co-occurring substance use. Her recent work has focused on the utility of behavioral economics in understanding PTSD. Dr. McDevitt-Murphy can be reached at [email protected] and on twitter @megintn James G. Murphy, Ph.D., is a Professor of Psychology at The University of Memphis. His research focuses primarily on alcohol and drug use disorder assessment, prevention, and treatment, with a particular focus on applications of behavioral economic theory. Dr. Murphy can be reached at [email protected] and on twitter @JgmurphyJim Rebecca J. Zakarian, M.S., (she/her) is a doctoral student at the University of Memphis, currently completing internship at VA Boston. Rebecca's research interests include the negative affect associated with PTSD, including anger, shame, and guilt. Her clinical interests include providing trauma-focused care for people with posttraumatic stress reactions and providing affirming care for LGBTQ+ people. Rebecca can be reached at [email protected]. John D., Roache, Ph.D., is a Professor of Psychiatry and also Pharmacology at The University of Texas Health Science Center at San Antonio and Chief of the Division of Alcohol & Drug Addiction. For nearly 40 years, his research interests have focused on Phase I, II, and III clinical trials designed to understand the causes, consequences, and treatments for substance use disorder. Stacey Young-McCaughan, Ph.D., R.N., is a Professor in the Department of Psychiatry & Behavioral Sciences at The University of Texas Health Science Center at San Antonio. She also serves as the Director of Research for STRONG STAR Consortium and the Consortium to Alleviate PTSD, which supported Dr. Olin’s research. Dr. Young-McCaughan’s research focuses on interventions for disorders such as PTSD among military personnel and veterans. Dr. Young-McCaughan can be reached at [email protected]. Brett T. Litz, Ph.D., is a Professor in the Department of Psychiatry at Boston University School of Medicine and the Department of Psychological and Brain Sciences in the Boston University School of Arts & Sciences, as well as the Director of the Mental Health Core of the Massachusetts Veterans Epidemiological Research and Information Center at the VA Boston Healthcare System. He also serves as Assessment Core Director for the STRONG STAR Consortium and the Consortium to Alleviate PTSD. Dr. Litz is internationally recognized as an expert on PTSD, military trauma, and the early intervention and treatment of trauma, traumatic loss, and moral injury. Dr. Litz can be reached at [email protected]. Terence M. Keane, Ph.D., is Professor of Psychiatry and Clinical Psychology at Boston University. Assistant Dean of VA Research, Keane is also the Associate Chief of Staff for Research and Development at VA Boston Healthcare System and Director of the National Center for Posttraumatic Stress Disorder’s Behavioral Science Division. He is recognized as a world leader in the field of traumatic stress. His current work and interests are in the development of a national VA registry of PTSD patients and the construction of an internet-based treatment program to assist in the readjustment of returning war veterans with post-deployment behavioral health problems. Dr. Keane can be reached at [email protected]. Alan L. Peterson, Ph.D., ABPP, is Aaron and Bobbie Elliott Krus Endowed Chair in Psychiatry and Professor and Chief of the Division of Behavioral Medicine in the Department of Psychiatry and Behavioral Sciences at The University of Texas Health Science Center at San Antonio. He is Director of the STRONG STAR Consortium and the Consortium to Alleviate PTSD. His research and publications focus on posttraumatic stress disorder, tobacco cessation, pain management, weight management, insomnia, temporomandibular disorders, tic disorders, aerophagia, and blepharospasm. Dr. Peterson can be reached at [email protected]. References Cited Amlung, M., Marsden, E., Holshausen, K., Morris, V., Patel, H., Vedelago, L., Naish, K. R., Reed, D. D., & McCabe, R. E. (2019). Delay Discounting as a transdiagnostic process in psychiatric disorders: A meta-analysis. JAMA Psychiatry, 76(11), 1176–1186. Bickel, W. K., Johnson, M. W., Koffarnus, M. N., MacKillop, J., & Murphy, J. G. (2014). 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