Cavus H A, Msetfi Rachel M
Centre for Social Issues Research, Department of Psychology, University of Limerick, Limerick, Ireland.
Centre for Social Issues Research, Department of Psychology, University of Limerick, Limerick, Ireland; Health Research Institute, University of Limerick, Limerick, Ireland.
Acta Psychol (Amst). 2016 Nov;171:47-56. doi: 10.1016/j.actpsy.2016.09.005. Epub 2016 Sep 20.
When there is no contingency between actions and outcomes, but outcomes occur frequently, people tend to judge that they have control over those outcomes, a phenomenon known as the outcome density (OD) effect. Recent studies show that the OD effect depends on the duration of the temporal interval between action-outcome conjunctions, with longer intervals inducing stronger effects. However, under some circumstances OD effect is reduced, for example when participants are mildly depressed. We reasoned that working memory (WM) plays an important role in learning of context; with reduced WM capacity to process contextual information during intertrial intervals (ITIs) during contingency learning might lead to reduced OD effects (limited capacity hypothesis). To test this, we used a novel dual-task procedure that increases the WM load during the ITIs of an operant (e.g., action-outcome) contingency learning task to impact contextual learning. We tested our hypotheses in groups of students with zero (Experiments 1, N=34), and positive contingencies (Experiment 2, N=34). The findings indicated that WM load during the ITIs reduced the OD effects compared to no load conditions (Experiment 1 and 2). In Experiment 2, we observed reduced OD effects on action judgements under high load in zero and positive contingencies. However, the participants' judgements were still sensitive to the difference between zero and positive contingencies. We discuss the implications of our findings for the effects of depression and context in contingency learning.
当行为与结果之间不存在偶然性，但结果频繁出现时，人们往往会判断自己能够控制这些结果，这一现象被称为结果密度（OD）效应。最近的研究表明，OD效应取决于行为 - 结果联结之间的时间间隔时长，间隔越长，效应越强。然而，在某些情况下OD效应会减弱，例如当参与者处于轻度抑郁状态时。我们推测工作记忆（WM）在情境学习中起着重要作用；在偶然性学习过程中的试验间隔期（ITIs），若处理情境信息的WM能力下降，可能会导致OD效应减弱（有限容量假说）。为了验证这一点，我们采用了一种新颖的双任务程序，在操作性（如行为 - 结果）偶然性学习任务的ITIs期间增加WM负荷，以影响情境学习。我们在零偶然性（实验1，N = 34）和正偶然性（实验2，N = 34）的学生群体中检验了我们的假设。研究结果表明，与无负荷条件相比，ITIs期间的WM负荷降低了OD效应（实验1和2）。在实验2中，我们观察到在高负荷下，零偶然性和正偶然性条件下对行为判断的OD效应均降低。然而，参与者的判断仍然对零偶然性和正偶然性之间的差异敏感。我们讨论了我们的研究结果对偶然性学习中抑郁和情境效应的影响。
