In 1908 psychologists Robert Yerkes and John Dodson performed a set of experiments on mice, and changed the way we understand stress.
Using mild electric shocks, they taught the mice to learn tasks and adopt habits more quickly.
Their original hypothesis was that as cognitive arousal is increased, the ability to perform tasks and form habits would increase in turn. However, this was only true up to a certain point, later referred to as the optimal level.
Beyond that point, as the strength of the shocks was increased, the ability of the mice to learn tasks diminished due to the excess mental overhead of trying to avoid the shock while simultaneously attempting the task.
The second part might seem common sense on the surface.
If I was getting electric shocks I’m sure I’d be terrible at performing tasks too.
The interesting part though, is that there is a certain level of cognitive stress we can undertake that actually improves our performance.
This arousal is sufficient motivation to make us focus. The little buzz in the back of your head when confronted with a stimulating challenge that makes you sit up and pay attention.
If you don’t get enough stress or cognitive arousal, you’ll feel bored and unfulfilled.
But when that state of arousal is too strong, anxiety rises and performance deteriorates.
Unfortunately in practice, you can’t magically pinpoint the optimum level of cognitive arousal that will maximise your output.
The optimal level will differ from person to person, and also based on the task at hand.
Complex tasks will require a lower level of arousal while simpler tasks might require much higher amounts. You just need a sufficient level of stimuli to induce focus.