Hauser Tobias U, Moutoussis Michael, Iannaccone Reto, Brem Silvia, Walitza Susanne, Drechsler Renate, Dayan Peter, Dolan Raymond J
Wellcome Trust Centre for Neuroimaging, University College London, London, United Kingdom.
Max Planck UCL Centre for Computational Psychiatry and Ageing Research, London, United Kingdom.
PLoS Comput Biol. 2017 Apr 12;13(4):e1005440. doi: 10.1371/journal.pcbi.1005440. eCollection 2017 Apr.
Patients with obsessive-compulsive disorder (OCD) can be described as cautious and hesitant, manifesting an excessive indecisiveness that hinders efficient decision making. However, excess caution in decision making may also lead to better performance in specific situations where the cost of extended deliberation is small. We compared 16 juvenile OCD patients with 16 matched healthy controls whilst they performed a sequential information gathering task under different external cost conditions. We found that patients with OCD outperformed healthy controls, winning significantly more points. The groups also differed in the number of draws required prior to committing to a decision, but not in decision accuracy. A novel Bayesian computational model revealed that subjective sampling costs arose as a non-linear function of sampling, closely resembling an escalating urgency signal. Group difference in performance was best explained by a later emergence of these subjective costs in the OCD group, also evident in an increased decision threshold. Our findings present a novel computational model and suggest that enhanced information gathering in OCD can be accounted for by a higher decision threshold arising out of an altered perception of costs that, in some specific contexts, may be advantageous.
患有强迫症(OCD)的患者可被描述为谨慎且犹豫不决,表现出过度的优柔寡断,这阻碍了高效决策。然而,在决策时过度谨慎在某些特定情况下,即深思熟虑成本较小的情况下,也可能导致更好的表现。我们将16名青少年强迫症患者与16名匹配的健康对照者进行比较,让他们在不同的外部成本条件下执行一项顺序信息收集任务。我们发现,强迫症患者的表现优于健康对照者,赢得了更多分数。两组在做出决定前所需要的平局次数上也存在差异,但在决策准确性方面没有差异。一种新颖的贝叶斯计算模型表明,主观抽样成本作为抽样的非线性函数出现,与不断升级的紧急信号非常相似。强迫症组这些主观成本出现得较晚,这在决策阈值增加中也很明显,这最能解释两组在表现上的差异。我们的研究结果提出了一种新颖的计算模型,并表明强迫症中增强的信息收集可以通过对成本的感知改变而产生的更高决策阈值来解释,在某些特定情况下,这可能是有利的。