Reimer Christina B, Schubert Torsten
Department of Psychology, Martin-Luther-Universität Halle-Wittenberg, Emil-Abderhalden-Str. 26-27, 06108, Halle (Saale), Germany.
Department of Psychology, Humboldt-Universität zu Berlin, Rudower Chaussee 18, 12489, Berlin, Germany.
Psychol Res. 2019 Apr;83(3):459-475. doi: 10.1007/s00426-017-0906-2. Epub 2017 Sep 15.
Both response selection and visual attention are limited in capacity. According to the central bottleneck model, the response selection processes of two tasks in a dual-task situation are performed sequentially. In conjunction search, visual attention is required to select the items and to bind their features (e.g., color and form), which results in a serial search process. Search time increases as items are added to the search display (i.e., set size effect). When the search display is masked, visual attention deployment is restricted to a brief period of time and target detection decreases as a function of set size. Here, we investigated whether response selection and visual attention (i.e., feature binding) rely on a common or on distinct capacity limitations. In four dual-task experiments, participants completed an auditory Task 1 and a conjunction search Task 2 that were presented with an experimentally modulated temporal interval between them (Stimulus Onset Asynchrony, SOA). In Experiment 1, Task 1 was a two-choice discrimination task and the conjunction search display was not masked. In Experiment 2, the response selection difficulty in Task 1 was increased to a four-choice discrimination and the search task was the same as in Experiment 1. We applied the locus-of-slack method in both experiments to analyze conjunction search time, that is, we compared the set size effects across SOAs. Similar set size effects across SOAs (i.e., additive effects of SOA and set size) would indicate sequential processing of response selection and visual attention. However, a significantly smaller set size effect at short SOA compared to long SOA (i.e., underadditive interaction of SOA and set size) would indicate parallel processing of response selection and visual attention. In both experiments, we found underadditive interactions of SOA and set size. In Experiments 3 and 4, the conjunction search display in Task 2 was masked. Task 1 was the same as in Experiments 1 and 2, respectively. In both experiments, the d' analysis revealed that response selection did not affect target detection. Overall, Experiments 1-4 indicated that neither the response selection difficulty in the auditory Task 1 (i.e., two-choice vs. four-choice) nor the type of presentation of the search display in Task 2 (i.e., not masked vs. masked) impaired parallel processing of response selection and conjunction search. We concluded that in general, response selection and visual attention (i.e., feature binding) rely on distinct capacity limitations.
反应选择和视觉注意在容量上都是有限的。根据中央瓶颈模型，在双任务情境中两个任务的反应选择过程是顺序进行的。在联合搜索中，需要视觉注意来选择项目并绑定它们的特征（例如颜色和形状），这导致了一个串行搜索过程。随着项目添加到搜索显示中（即集大小效应），搜索时间会增加。当搜索显示被掩蔽时，视觉注意的部署被限制在一段短暂的时间内，并且目标检测会随着集大小的增加而降低。在这里，我们研究了反应选择和视觉注意（即特征绑定）是依赖于共同的还是不同的容量限制。在四个双任务实验中，参与者完成了一个听觉任务1和一个联合搜索任务2，它们之间以实验调制的时间间隔呈现（刺激开始异步，SOA）。在实验1中，任务1是一个二选一的辨别任务，联合搜索显示没有被掩蔽。在实验2中，任务1中的反应选择难度增加到四选一的辨别，搜索任务与实验1相同。我们在两个实验中都应用了松弛位点方法来分析联合搜索时间，也就是说，我们比较了不同SOA下的集大小效应。不同SOA下相似的集大小效应（即SOA和集大小的相加效应）将表明反应选择和视觉注意的顺序处理。然而，与长SOA相比，短SOA下显著更小的集大小效应（即SOA和集大小的次相加交互作用）将表明反应选择和视觉注意的并行处理。在两个实验中，我们都发现了SOA和集大小的次相加交互作用。在实验3和4中，任务2中的联合搜索显示被掩蔽。任务1分别与实验1和2相同。在两个实验中，d'分析表明反应选择不影响目标检测。总体而言，实验1 - 4表明，听觉任务1中的反应选择难度（即二选一与四选一）以及任务2中搜索显示的呈现类型（即未被掩蔽与被掩蔽）都不会损害反应选择和联合搜索的并行处理。我们得出结论，一般来说，反应选择和视觉注意（即特征绑定）依赖于不同的容量限制。
