基础定义

耶克斯-多德森定律(The Yerks_Dodson Law)表明，学内容越困难，学习效果越容易受到较高激动水平的干扰。激动水平处于适宜强度时，工作效率最佳；激动水平过低时，缺乏参与活动的积极性，工作效率不可能提高；激动水平超过顶峰时，工作效率会随强度增加而不断下降，因为过强的激动水平会使机体处于过度焦虑和紧张的心理状态，干扰记忆、思维等心理过程的正常活动。

中文定义

Yerkes-Dodson Law（耶克斯-多德森定律/耶克斯-多得森定律）是心理学家耶克斯（R.M Yerkes）与多德森（J.D Dodson）经实验研究归纳出的一种法则，用来解释心理压力、工作难度与作业成绩三者之间的关系。动机水平与工作效率之间的关系不是一种线性关系，而是倒U形曲线。中等强度的激动水平最有利于任务的完成。动机水平的最佳水平不是固定的，依据任务的不同性质会有所改变。在完成简单的任务中，动机水平高，效率可以达到最佳水平；在完成难度适中的任务中，中等的动机水平效率最高；在完成复杂和困难的任务中，偏低动机水平下的工作效率最佳。

英文原文

The Yerkes-Dodson law demonstrates an empirical relationship between arousal and performance. It dictates that performance increases with cognitive arousal, but only to a certain point: when levels of arousal become too high, performance will decrease. A corollary is that there is an optimal level of arousal for a given task.

It is a scientific principle developed by psychologists Robert M. Yerkes and J. D. Dodson in 1908 and is grounded within the discourses of biopsychology and neuroscience.

The process is often demonstrated graphically as an inverted U-shaped curve (curvilinear), increasing and then decreasing with higher levels of arousal. (However, there is also a linear component which proposes that in a simple task, performance increases with arousal. Therefore, in a simple task the relationship between arousal and performance is linear. According to the Yerkes-Dodson law, only in a difficult task is the relationship between arousal and performance curvilinear.)

It has been proposed that different tasks may require different levels of arousal. For example, difficult or intellectually demanding tasks may require a lower level of arousal for optimal performance (to facilitate concentration), whereas tasks demanding stamina or persistence may be performed better with higher levels of arousal (to increase motivation).

The effect of the difficulty of tasks later on led to the hypothesis that the Yerkes-Dodson Law can be decomposed into two distinct factors. The upward part of the converted U can be thought of as the energizing effect of arousal. The downward part on the other hand is caused by negative effects of arousal (or stress) on cognitive processes, like attention ("tunnel vision"), memory, and problem-solving.

There has been research indicating that the correlation suggested by Yerkes and Dodson exists (such as that of Broadhurst, 1959; Duffy, 1962; Anderson, 1988), but a cause of the correlation has not yet successfully been established (Anderson, Revelle, & Lynch, 1989).

Despite some evidence to the contrary, the law is generally respected.

所得结论

1、各种活动都存在一个最佳的动机水平。

2、动机水平的最佳水平随任务性质的不同而不同。

3、在难度较大的任务中，较低的动机水平有利于任务的完成。[1] 

什么人更能取得较好的作业成绩：

很显然，是那些可以灵活调整自己动机强度的人。因为在现实环境中，没有一个人总是在执行固定难度的任务，而是总会遇到不同性质的任务，显而易见，只有能够根据任务性质调整自己的动机的人才能够取得较好的成绩。

这需要做到以下几点：