Sensorimotor Neuroscience and Ageing Research Group, School of Psychological Sciences, College of Health and Medicine, University of Tasmania, Hobart, Australia.
School of Psychology, University of Newcastle, Newcastle, Australia.
PLoS One. 2023 Jul 7;18(7):e0288085. doi: 10.1371/journal.pone.0288085. eCollection 2023.
Rapid-choice decision-making is biased by prior probability of response alternatives. Conventionally, prior probability effects are assumed to selectively affect, response threshold, which determines the amount of evidence required to trigger a decision. However, there may also be effects on the rate at which evidence is accumulated and the time required for non-decision processes (e.g., response production). Healthy young (n = 21) and older (n = 20) adults completed a choice response-time task requiring left- or right-hand responses to imperative stimuli. Prior probability was manipulated using a warning stimulus that informed participants that a particular response was 70% likely (i.e., the imperative stimulus was either congruent or incongruent with the warning stimulus). In addition, prior probability was either fixed for blocks of trials (block-wise bias) or varied from trial-to-trial (trial-wise bias). Response time and accuracy data were analysed using the racing diffusion evidence-accumulation model to test the selective influence assumption. Response times for correct responses were slower on incongruent than congruent trials, and older adults' responses were slower, but more accurate, than young adults. Evidence-accumulation modelling favoured an effect of prior probability on both response thresholds and nondecision time. Overall, the current results cast doubt on the selective threshold influence assumption in the racing diffusion model.
快速选择决策受到反应替代方案先验概率的影响。传统上，先验概率效应被认为会选择性地影响决定的响应阈值，该阈值决定了触发决策所需的证据量。然而，它也可能会对证据积累的速度和非决策过程（例如，响应产生）所需的时间产生影响。健康的年轻（n=21）和年长（n=20）成年人完成了一个需要对强制性刺激做出左手或右手反应的选择反应时任务。使用警告刺激来操纵先验概率，告知参与者特定的反应有 70%的可能性（即，强制性刺激与警告刺激一致或不一致）。此外，先验概率要么在试验块中固定（块-wise 偏差），要么从试验到试验变化（试验-wise 偏差）。使用竞争扩散证据积累模型分析反应时间和准确性数据，以检验选择性影响假设。正确反应的反应时间在不一致试验中比一致试验中慢，而年长成年人的反应比年轻成年人慢，但更准确。证据积累模型支持先验概率对响应阈值和非决策时间都有影响。总的来说，当前的结果对竞争扩散模型中选择性阈值影响假设提出了质疑。
