How we change what others think, feel, believe and do
When we are fresh and alert, we make the best decisions we can with the information we have available. However, as we become tired, the quality of our decisions fade, such that a later reflection may result in us regretting the choices we made.
When there is a sequence of decisions to make, the greater the effort required for each decision, the greater will be the decay in decision quality. When there are many easier decisions, the quality will fade more slowly over time, but will still decline as decision fatigue sets in.
Decision fatigue is not like physical fatigue. You probably do not feel tired. But your decisions become distinctly less rational.
A couple are looking at houses to buy. They see a lot during one day. In the morning, they look carefully and compare things against their checklist. By the end of the afternoon they are just having a quick look around. In the evening, they find it very hard to work out which house would be best for them.
A business management board has a series of decisions to make during the day. Towards the end of the day they make several decisions that they later regret.
Making decisions takes effort and uses up blood glucose. And just as in the analogy of willpower as muscle, we tire as we make each decision, with harder decisions tiring us more. As we become tired, our self-control and other cognitive functioning fades, making us less able to accurately weigh up all the factors involved. As a result, we tend to make more subconscious and less careful conscious choices, with more 'gut feel' and rules of thumb that are less likely to give a good decision that careful conscious consideration.
Decision fatigue is not the same as physical fatigue. You are unlikely to feel tired and may not know you are fatigued. This can lead to bad decisions being made without realizing this is happening.
In a review of 1100 parole cases in Israeli prisons, Levav and Danziger found that prisoners were more likely to get paroled if they appeared before judges first thing in the morning. In fact they found a huge disparity, with prisoners appearing in the early morning being paroled about 70 percent of the time, while those who were up before the judges late in the afternoon received paroled less than 10 percent of the time.
When people are personally involved in the outcome of the decision, where it is very important to them, they will put more exhausting effort into the decision and suffer more from consequent anticipated regret if they worry that they may have made a wrong decision. A lack of involvement can also be tiring when the person is forced to decide. This is because they also have to battle against their own desire to give up or choose randomly.
The exhaustion that reduces self-control and results in poorer decisions is sometimes called ego depletion. It has been found that this is related to more activity in the nucleus accumbens and less in the amygdala (which helps in impulse control). When exhausted the brain thinks differently, not less. Ego depletion tips the balance more towards short-term rewards and away from longer-term benefits.
Once an exhausting decision is made and people become depleted they resist further discussion or choice, preferring just to get on with the job. This can also be seen in the careless inaction of people who have decided to give up on something.
Decision fatigue is used in situations such as cults, where exhaustion is used to confuse and suggest new ways of thinking. It is also useful in interrogation where the cognitive effort of lying means targets eventually become worn down and make errors.
The confusion principle in changing minds may use decision fatigue as a mentally exhausted person is more easily confused and so persuaded.
If you want to make good decisions, make them early in the day or when you are fresh. Do not make too many decisions at the same time or close together.
If you want others to make decisions they would not normally make, give them lots of other decisions to make beforehand and then guide them with suggestions as they enter decision fatigue and so tend more towards short-term rewards.
One way of knowing that a person is exhausted is where they seek and accept any advice. In this way shoppers who have tried (or been offered) everything will often ask the advice of the sales person.