The Yerkes-Dodson Law: The Relationship Between Performance And Motivation

The Yerkes-Dodson law suggests that performance and arousal are directly related. This law was developed by psychologists Robert M. Yerkes and John Dillingham Dodson in 1908.

The Yerkes-Dodson law dictates that performance increases with physiological or mental arousal, but only up to a point. When arousal levels become too high, performance decreases. According to this law, the best way to boost motivation and performance is to work with objective tasks that allow us to be alert.

In their experiment, Yerkes and Dodson discovered that rats could be motivated to complete a maze with mild electric shocks. However, when the crashes were of a higher degree, their performance level decreased and they simply ran with the intention of escaping. The experiment made it clear that arousal levels helped focus attention on the task at hand, but only up to an optimal point.

How the Yerkes-Dodson Law Works

An example of how the Yerkes-Dodson Act works is the anxiety you experience before a test. An optimal level of stress can help you focus on the test and remember the information. However, too much test anxiety can affect your ability to focus, making it harder to remember.

Another great example of how the Yerkes-Dodson law works is athletic performance. When an athlete is ready to make a major move, a certain ideal level of arousal – adrenaline release – can boost their performance and allow them to make the move. But when the athlete is overly stressed, they could get stuck or perform the movement in an energetic but imprecise way.

So what determines what level of arousal is ideal? In reality, there is no fixed answer to this question, since this level of arousal can vary from task to task.

For example, performance levels are known to decrease from a lower level of activation. This means that if you are doing a relatively simple task you can deal with a much larger range of activation levels.

Simple tasks, like making photocopies or doing housework, are less likely to be affected by very low or very high arousal levels. However, when performing much more complex tasks, performance would be much more influenced by low and high activation levels.

If the levels of arousal are too low, it is possible to have the feeling that there is a lack of energy to carry out the work. But arousal levels that are too high could be just as problematic, making it difficult to focus long enough to complete the task.

Inverted U model

The process described by Yerkes and Dodson is often graphically illustrated as a bell-shaped curve that increases and then decreases with higher levels of arousal. This is why the Yerkes-Dodson law is also known as the inverted U model.

Due to task differences, the shape of the curve can be highly variable. For simple or well-learned tasks, the relationship is monotonous, and performance improves as arousal increases. However, for complex, unknown, or difficult tasks, the relationship between arousal and performance reverses after a point, and performance decreases as arousal increases.

The rising part of the inverted U can be thought of as the energizing effect of arousal. The descending part is caused by the negative effects of arousal (or stress) on cognitive processes such as attention, memory, and problem solving.

According to the inverted U model, maximum performance is achieved when people experience a moderate level of pressure. When they experience too much or too little pressure, their performance decreases, sometimes severely.

• The left side of the graph shows the situation where people are unchallenged, see no reason to work hard on a task, or are in danger of approaching their work in a careless and unmotivated way.
• The middle of the graph shows where you are working most effectively, when you are motivated enough to work hard without being overloaded.

• The right side of the graph shows where you are beginning to give in to pressure, to be overwhelmed.

The four influencing factors

The inverted U-curve model is different from individual to individual depending on the situation. There are actually four influencing factors that can affect this curve, which are skill level, personality, anxiety trait, and task complexity.

The skill level of an individual also affects his performance in the given task. A highly trained individual, who is confident in his ability, is more likely to cope well with situations where pressure is high, as the person could rely on his well-rehearsed responses.

An individual’s personality also affects the way they handle pressure. Psychologists believe that extroverts are better at handling pressure than introverts. Also, introverts do better in the absence of pressure.

Regarding the anxiety trait,  the confidence that a person has in himself also affects the way he handles any situation. A person is more likely to maintain their composure under pressure if their self-confidence is high and they do not repeatedly question their own abilities.

Finally, the level of difficulty of the task is another factor that influences an individual’s performance. The difficulty of making photocopies is not the same as having to write a report or an essay. In any case, the level of complexity of any task varies from person to person.

Final comments

Despite being over a century old, the Yerkes-Dodson Act is very useful today. In fact, research has continued in this line, especially to apply it to work and sports performance.

Research conducted between the 1950s and 1980s has confirmed that there is a correlation between elevated levels of stress and improved motivation and focus, although an exact cause for the correlation has not been established.

As recently as 2007, researchers suggested that the correlation is related to the brain’s production of stress hormones which, when measured during memory performance tests, demonstrated a curve similar to the Yerkes-Dodson experiment. Furthermore, the research showed a positive correlation with good memory performance, suggesting that these hormones may also be responsible for the Yerkes-Dodson effect.