Faculty of Arts and Social Sciences, Sabanci University, Istanbul, Turkey.
School of Psychology, University of Kent, Canterbury, UK.
J Behav Ther Exp Psychiatry. 2021 Dec;73:101672. doi: 10.1016/j.jbtep.2021.101672. Epub 2021 Jun 25.
People high in trait anxiety or depression overestimate the probability of negative events, and underestimate the probability of positive events, relative to people low in trait anxiety and depression. Although this probability bias may be fundamental to some emotional disorders, its causes are not well understood. The dominant explanations are based on the availability heuristic: people relatively high in anxiety or depression find it relatively easy to imagine reasons why bad things might happen to them, and this affects their probability estimates. We tested, for the first time, whether individual differences in the availability of such reasons mediate the relationships between trait anxiety or depression and probability bias, in a nonclinical sample.
Two hundred and seventy-eight undergraduates generated reasons why a set of positive and negative events might vs. might not happen to them, before rating those events' probability and potential impact on their lives.
Individual differences in the availability of reasons why good and bad events might vs. might not happen did not mediate the sizeable relationships between trait anxiety and probability bias, and between trait depression and probability bias; these relationships remained significant when availability was controlled. Results for the impact of events ('cost bias') were less clear.
Replication with patient groups would be invaluable; different operationalisations of availability may change the results.
Availability can influence probability estimates, but it does not explain why we see probability bias in people with high trait anxiety or depression.
相对于低特质焦虑和低特质抑郁的人，高特质焦虑或抑郁的人会高估负面事件的发生概率，低估正面事件的发生概率。虽然这种概率偏差可能是某些情绪障碍的基础，但它的原因尚不清楚。主流解释基于可得性启发式：相对焦虑或抑郁程度较高的人，他们会相对容易想象出可能导致自己遭遇坏事的原因，而这会影响他们的概率估计。我们首次在非临床样本中测试了，特质焦虑或抑郁与概率偏差之间的关系是否可以通过此类原因的可得性个体差异来进行中介。
278 名大学生在对一系列正面和负面事件发生的可能性及其对生活的潜在影响进行评分之前，先生成这些事件可能发生和不可能发生的原因。
在特质焦虑与概率偏差之间，以及在特质抑郁与概率偏差之间，好的和坏的事件可能发生和不可能发生的原因的可得性个体差异，均不能中介概率偏差的大小；当控制可得性时，这些关系仍然显著。对于事件影响的结果（“成本偏差”）则不太明确。
患者群体的重复验证将是非常宝贵的；不同的可得性操作可能会改变结果。
可得性能影响概率估计，但它并不能解释为什么我们会在高特质焦虑或抑郁的人中看到概率偏差。
