Department of Psychology, University of Texas, 5.316 Neural and Molecular Sciences Bldg., 2506 Speedway Boulevard, Austin, TX, USA.
J Exp Psychol Hum Percept Perform. 2012 Apr;38(2):489-97. doi: 10.1037/a0026065. Epub 2011 Nov 21.
Two Bayesian observer models were recently proposed to account for data from the Eriksen flanker task, in which flanking items interfere with processing of a central target. One model assumes that interference stems from a perceptual bias to process nearby items as if they are compatible, and the other assumes that the interference is due to spatial uncertainty in the visual system (Yu, Dayan, & Cohen, 2009). Both models were shown to produce one aspect of the empirical data, the below-chance dip in accuracy for fast responses to incongruent trials. However, the models had not been fit to the full set of behavioral data from the flanker task, nor had they been contrasted with other models. The present study demonstrates that neither model can account for the behavioral data as well as a comparison spotlight-diffusion model. Both observer models missed key aspects of the data, challenging the validity of their underlying mechanisms. Analysis of a new hybrid model showed that the shortcomings of the observer models stem from their assumptions about visual processing, not the use of a Bayesian decision process.
最近提出了两种贝叶斯观测者模型，以解释艾瑞克森侧翼任务中的数据，其中侧翼项目会干扰对中央目标的处理。一种模型假设干扰源自于一种知觉偏差，即把附近的项目视为相容的，而另一种模型则假设干扰是由于视觉系统中的空间不确定性（Yu、Dayan 和 Cohen，2009）。这两种模型都能够产生经验数据的一个方面，即对不一致试验的快速反应的准确性低于机会水平的下降。然而，这些模型尚未拟合侧翼任务的全部行为数据，也没有与其他模型进行对比。本研究表明，没有一种模型能够像比较聚光灯扩散模型那样很好地解释行为数据。两种观测者模型都忽略了数据的关键方面，这对其潜在机制的有效性提出了挑战。对一种新的混合模型的分析表明，观测者模型的缺点源于它们对视觉处理的假设，而不是对贝叶斯决策过程的使用。
