Department of Psychology, Simon Fraser University, Burnaby, BC, Canada.
Q J Exp Psychol (Hove). 2022 Aug;75(8):1561-1570. doi: 10.1177/17470218211054750. Epub 2021 Oct 26.
When the visual system is busy processing one stimulus, it has problems processing a subsequent stimulus if it arrives soon after the first. Laboratory studies of this second-stimulus impairment-known as ()-have employed two targets (T1, T2) presented in rapid sequence, and have found identification accuracy to be nearly perfect for T1, but impaired for T2. It is commonly believed that the magnitude of the AB is related directly to the difficulty of T1: the greater the T1 difficulty, the larger the AB. A survey of the experimental literature disconfirms that belief showing it to have arisen from artificial constraints imposed by the 100% limit of the response scale. Removal of that constraint, either using reaction time (RT) instead of accuracy as the dependent measure, or in experiments in which the functions of T2 accuracy over lags do not converge to the limit of the response scale, reveals parallel functions for the easy-T1 and the hard-T1 conditions, consistent with the idea that T1 difficulty does not modulate AB magnitude. This finding is problematic for all, but the Boost and Bounce (B&B) and the Locus Coeruleus-Norepinephrine (LC-NE) theories in which T1 acts merely as a trigger for an eventual refractory period that leads to the failure to process T2, rendering T1 difficulty and its relationship to the AB an irrelevant consideration.
当视觉系统忙于处理一个刺激时，如果第二个刺激很快就出现，它就会处理第二个刺激有困难。对这种第二种刺激损伤的实验室研究（）-采用了两个目标（T1、T2）的快速序列呈现，并发现 T1 的识别准确性几乎是完美的，但 T2 的识别准确性受损。人们普遍认为，AB 的大小与 T1 的难度直接相关：T1 难度越大，AB 越大。对实验文献的调查否定了这一信念，表明这一信念源于反应量表 100%限制所施加的人为约束。消除这种约束，无论是使用反应时间 (RT) 代替准确性作为因变量，还是在 T2 准确性滞后的函数不收敛到反应量表限制的实验中，都揭示了容易 T1 和困难 T1 条件的平行函数，这与 T1 难度不会调节 AB 大小的观点一致。这一发现对所有理论都是一个问题，除了 Boost 和 Bounce（B&B）和蓝斑去甲肾上腺素（LC-NE）理论，在这些理论中，T1 只是作为一个最终的不应期的触发因素，导致无法处理 T2，使 T1 的难度及其与 AB 的关系成为一个无关的考虑因素。
