Department of Psychology, University of Otago, Dunedin, 9054, New Zealand.
Atten Percept Psychophys. 2021 Jan;83(1):356-388. doi: 10.3758/s13414-020-02143-7. Epub 2020 Sep 30.
Four experiments investigated the extent to which a limited pool of resources can be shared between different tasks performed simultaneously when it is efficient to do so. The experiments used a prioritized processing paradigm, in which stimuli for both a primary task and a background task were presented in each trial. If the primary-task stimulus required a response in a trial, participants made only that response. If the primary-task stimulus did not require a response, participants responded to the background task. The main manipulation was the relative probability that a response would be required to the primary versus background task. In some blocks, the majority of trials required responses to the primary task (Experiments 1 and 2: 80%; Experiments 3 and 4: 60%), whereas in other blocks the majority required responses to the background task. Background-task responses were substantially faster in blocks where they were more likely to be required, consistent with the idea that more capacity was allocated to them in these blocks. Backward compatibility effects on primary-task responses and stimulus-onset asynchrony effects on background-task responses provided further evidence of greater capacity allocation to the background task when there was a higher probability of responding to it. The results support the view that two tasks can be processed in parallel, with resources divided between them, when it is efficient to do so.
四个实验研究了当同时进行的不同任务之间的资源共享是有效时，资源在多大程度上可以共享。这些实验使用了优先级处理范式，其中每个试验都呈现了主要任务和背景任务的刺激。如果主要任务刺激需要在试验中做出响应，参与者只需做出该响应。如果主要任务刺激不需要响应，则参与者响应背景任务。主要的操作是响应主要任务与背景任务的相对概率。在一些块中，大多数试验都需要对主要任务做出响应（实验 1 和 2：80%；实验 3 和 4：60%），而在其他块中，大多数试验需要对背景任务做出响应。在更有可能需要背景任务响应的块中，背景任务响应要快得多，这与在这些块中分配更多容量的观点一致。对主要任务响应的向后兼容性效应和对背景任务响应的刺激起始异步效应进一步证明了当更有可能响应背景任务时，会向其分配更多的容量。结果支持这样一种观点，即当这样做有效时，两个任务可以并行处理，资源在它们之间分配。
