The U-shaped curve has long been recognized as a fundamental concept in psychological science, particularly in theories about motivational accounts and cognitive control. In this study (N = 330), we empirically tested the prediction of a nonmonotonic, curvilinear relationship between task difficulty and control adaptation. Drawing from motivational intensity theory and the expected value of control framework, we hypothesized that control intensity would increase with task difficulty until a maximum tolerable level, after which it would decrease. To examine this hypothesis, we conducted two experiments utilizing Stroop-like conflict tasks, systematically manipulating the number of distractors to vary task difficulty. We assessed control adaptation and measured subjective task difficulty. Our results revealed a curvilinear pattern between perceived task difficulty and adaptation of control. The findings provide empirical support for the theoretical accounts of motivational intensity theory and expected value of control, highlighting the nonlinear nature of the relationship between task difficulty and cognitive control. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

中文翻译：

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控制曲线：任务难度对认知控制的非单调影响。


U 形曲线长期以来一直被认为是心理科学的一个基本概念，尤其是在关于动机账户和认知控制的理论中。在这项研究 （N = 330） 中，我们实证检验了任务难度和控制适应之间非单调曲线关系的预测。借鉴激励强度理论和控制框架的期望值，我们假设控制强度会随着任务难度的增加而增加，直到达到最大可容忍水平，之后它会降低。为了验证这一假设，我们利用类似 Stroop 的冲突任务进行了两个实验，系统地操纵干扰因素的数量来改变任务难度。我们评估了控制适应并测量了主观任务难度。我们的结果揭示了感知任务难度和控制适应之间的曲线模式。研究结果为动机强度理论和控制期望值的理论解释提供了实证支持，突出了任务难度与认知控制之间关系的非线性性质。（PsycInfo 数据库记录 （c） 2024 APA，保留所有权利）。