CNRS UMR 9193-SCALab-Sciences Cognitives et Sciences Affectives.
School of Psychology.
J Exp Psychol Anim Learn Cogn. 2022 Jul;48(3):190-202. doi: 10.1037/xan0000334.
In a signal detection theory approach to associative learning, the perceived (i.e., subjective) contingency between a cue and an outcome is a random variable drawn from a Gaussian distribution. At the end of the sequence, participants report a positive cue-outcome contingency provided the subjective contingency is above some threshold. Some researchers have suggested that the mean of the subjective contingency distributions and the threshold are controlled by different variables. The present data provide empirical support for this claim. In three experiments, participants were exposed to rapid streams of trials at the end of which they had to indicate whether a target outcome O1 was more likely following a target cue X. Interfering treatments were incorporated in some streams to impend participants' ability to identify the objective X-O1 contingency: interference trials (X was paired with an irrelevant outcome O2), nonreinforced trials (X was presented alone), plus control trials (an irrelevant cue W was paired with O2). Overall, both interference and nonreinforced trials impaired participants' sensitivity to the contingencies as measured by signal detection theory's d', but they also enhanced detection of positive contingencies through a cue density effect, with nonreinforced trials being more susceptible to this effect than interference trials. These results are explicable if one assumes interference and nonreinforced trials impact the mean of the associative strength distribution, while the cue density influences the threshold. (PsycInfo Database Record (c) 2022 APA, all rights reserved).
在联想学习的信号检测理论方法中,线索与结果之间的感知(即主观)关联是从正态分布中抽取的随机变量。在序列结束时,如果主观关联高于某个阈值,参与者就会报告正的线索-结果关联。一些研究人员认为,主观关联分布的均值和阈值由不同的变量控制。本研究数据为这一观点提供了经验支持。在三个实验中,参与者会在快速的试验流中接受刺激,在试验结束时,他们必须指出目标结果 O1 是否更有可能出现在目标线索 X 之后。在一些试验流中加入了干扰处理,以影响参与者识别客观 X-O1 关联的能力:干扰试验(X 与不相关的结果 O2 配对)、非强化试验(X 单独呈现),以及控制试验(无关线索 W 与 O2 配对)。总的来说,干扰和非强化试验都降低了参与者对关联的敏感性,这可以通过信号检测理论的 d'来衡量,但它们也通过线索密度效应增强了对正关联的检测,而非强化试验比干扰试验更容易受到这种效应的影响。如果假设干扰和非强化试验影响关联强度分布的均值,而线索密度影响阈值,那么这些结果是可以解释的。