Department of Psychology, University of Freiburg, Engelbergerstraße 41, Freiburg, 79085, Germany.
University of Otago, Otago, New Zealand.
Mem Cognit. 2018 Jul;46(5):699-715. doi: 10.3758/s13421-018-0802-z.
In the present study, we introduce a novel, self-organized task-switching paradigm that can be used to study more directly the determinants of switching. Instead of instructing participants to randomly switch between tasks, as in the classic voluntary task-switching paradigm (Arrington & Logan, 2004), we instructed participants to optimize their task performance in a voluntary task-switching environment in which the stimulus associated with the previously selected task appeared in each trial after a delay. Importantly, the stimulus onset asynchrony (SOA) increased further with each additional repetition of this task, whereas the stimulus needed for a task switch was always immediately available. We conducted two experiments with different SOA increments (i.e., Exp. 1a = 50 ms, Exp. 1b = 33 ms) to see whether this procedure would induce switching behavior, and we explored how people trade off switch costs against the increasing availability of the stimulus needed for a task repetition. We observed that participants adapted their behavior to the different task environments (i.e., SOA increments) and that participants switched tasks when the SOA in task switches approximately matched the switch costs. Moreover, correlational analyses indicated relations between individual switch costs and individual switch rates across participants. Together, these results demonstrate that participants were sensitive to the increased availability of switch stimuli in deciding whether to switch or to repeat, which in turn demonstrates flexible adaptive task selection behavior. We suggest that performance limitations in task switching interact with the task environment to influence switching behavior.
在本研究中，我们引入了一种新颖的、自组织的任务转换范式，可以更直接地研究转换的决定因素。与经典的自愿任务转换范式（Arrington & Logan, 2004）中指示参与者随机在任务之间转换不同，我们指示参与者在自愿任务转换环境中优化任务表现，在这种环境中，与先前选择的任务相关的刺激在延迟后每次试验中出现。重要的是，随着这种任务的每次额外重复，刺激呈现时间间隔（SOA）进一步增加，而任务转换所需的刺激始终是立即可用的。我们进行了两项具有不同 SOA 增量的实验（即，实验 1a = 50 毫秒，实验 1b = 33 毫秒），以观察这种程序是否会引起转换行为，并探索人们如何权衡转换成本与任务重复所需刺激的可用性增加之间的关系。我们观察到参与者根据不同的任务环境（即 SOA 增量）调整了他们的行为，并且当任务转换中的 SOA 大致与转换成本相匹配时，参与者会进行任务转换。此外，相关分析表明，参与者之间的个体转换成本和个体转换率之间存在关系。总之，这些结果表明，参与者能够根据开关刺激的可用性增加来决定是否进行切换或重复，这反过来又证明了灵活自适应的任务选择行为。我们认为，任务转换中的性能限制与任务环境相互作用，影响转换行为。
