Department of Psychology, The Ohio State University.
Psychol Rev. 2018 Jan;125(1):33-46. doi: 10.1037/rev0000080. Epub 2017 Oct 16.
It is important to identify sources of variability in processing to understand decision-making in perception and cognition. There is a distinction between internal and external variability in processing, and double-pass experiments have been used to estimate their relative contributions. In these and our experiments, exact perceptual stimuli are repeated later in testing, and agreement on the 2 trials is examined to see if it is greater than chance. In recent research in modeling decision processes, some models implement only (internal) variability in the decision process whereas others explicitly represent multiple sources of variability. We describe 5 perceptual double-pass experiments that show greater than chance agreement, which is inconsistent with models that assume internal variability alone. Estimates of total trial-to-trial variability in the evidence accumulation (drift) rate (the decision-relevant stimulus information) were estimated from fits of the standard diffusion decision-making model to the data. The double-pass procedure provided estimates of how much of this total variability was systematic and dependent on the stimulus. These results provide the first behavioral evidence independent of model fits for trial-to-trial variability in drift rate in tasks used in examining perceptual decision-making. (PsycINFO Database Record
识别处理过程中的变异性来源对于理解感知和认知中的决策非常重要。处理过程中的变异性有内部变异性和外部变异性之分，双通实验被用来估计它们的相对贡献。在这些和我们的实验中，精确的感知刺激在测试中稍后重复，然后检查两次试验的一致性是否大于偶然。在最近关于决策过程建模的研究中，一些模型仅在决策过程中实现（内部）变异性，而另一些模型则明确表示存在多种变异性来源。我们描述了 5 个感知双通实验，这些实验显示出大于偶然的一致性，这与仅假设内部变异性的模型不一致。从标准扩散决策模型对数据的拟合中，估计了证据积累（漂移）率（与决策相关的刺激信息）在总试验间变异性中的估计值。双通程序提供了关于这种总变异性中有多少是系统的和依赖于刺激的估计。这些结果提供了第一个行为证据，独立于模型拟合，证明了在用于检验感知决策的任务中漂移率的试验间变异性。
