Lasagna Carly A, Pleskac Timothy J, Burton Cynthia Z, McInnis Melvin G, Taylor Stephan F, Tso Ivy F
Department of Psychology, University of Michigan, Ann Arbor, Michigan.
Department of Psychiatry, University of Michigan, Ann Arbor, Michigan.
Comput Psychiatr. 2022;6(1):96-116. doi: 10.5334/cpsy.61. Epub 2022 May 24.
Bipolar disorder (BD) is associated with excessive pleasure-seeking risk-taking behaviors that often characterize its clinical presentation. However, the mechanisms of risk-taking behavior are not well-understood in BD. Recent data suggest prior substance use disorder (SUD) in BD may represent certain trait-level vulnerabilities for risky behavior. This study examined the mechanisms of risk-taking and the role of SUD in BD via mathematical modeling of behavior on the Balloon Analogue Risk Task (BART). Three groups-18 euthymic BD with prior SUD (BD+), 15 euthymic BD without prior SUD (BD-), and 33 healthy comparisons (HC)-completed the BART. We modeled behavior using 4 competing hierarchical Bayesian models, and model comparison results favored the Exponential-Weight Mean-Variance (EWMV) model, which encompasses and delineates five cognitive components of risk-taking: prior belief, learning rate, risk preference, loss aversion, and behavioral consistency. Both BD groups, regardless of SUD history, showed lower behavioral consistency than HC. BD+ exhibited more pessimistic prior beliefs (relative to BD- and HC) and reduced loss aversion (relative to HC) during risk-taking on the BART. Traditional measures of risk-taking on the BART (adjusted pumps, total points, total pops) detected no group differences. These findings suggest that reduced behavioral consistency is a crucial feature of risky decision-making in BD and that SUD history in BD may signal additional trait vulnerabilities for risky behavior even when mood symptoms and substance use are in remission. This study also underscores the value of using mathematical modeling to understand behavior in research on complex disorders like BD.
双相情感障碍（BD）与过度追求享乐的冒险行为有关，这些行为往往是其临床表现的特征。然而，BD中冒险行为的机制尚未得到充分理解。最近的数据表明，BD患者先前存在物质使用障碍（SUD）可能代表了冒险行为的某些特质水平的脆弱性。本研究通过对气球模拟风险任务（BART）中的行为进行数学建模，研究了BD中冒险行为的机制以及SUD的作用。三组——18名有先前SUD的心境正常的BD患者（BD+）、15名无先前SUD的心境正常的BD患者（BD-）和33名健康对照者（HC）——完成了BART。我们使用4种相互竞争的分层贝叶斯模型对行为进行建模，模型比较结果支持指数加权均值-方差（EWMV）模型，该模型包含并描绘了冒险行为的五个认知成分：先验信念、学习率、风险偏好、损失厌恶和行为一致性。两个BD组，无论SUD病史如何，其行为一致性均低于HC组。在BART的冒险过程中，BD+组表现出更悲观的先验信念（相对于BD-组和HC组），并且损失厌恶降低（相对于HC组）。BART上传统的冒险测量指标（调整后的打气次数、总点数、总爆破次数）未检测到组间差异。这些发现表明，行为一致性降低是BD中冒险决策的一个关键特征，并且BD中的SUD病史可能表明即使情绪症状和物质使用处于缓解期，冒险行为仍存在额外的特质脆弱性。本研究还强调了使用数学建模来理解BD等复杂疾病研究中的行为的价值。
