Judges are more lenient after a meal

An interesting experiment was conducted in Israel. The decisions of judges granting parole (i.e., allowing a prisoner to get out of jail after serving a certain amount of a prison sentence) depended very much on when the case for parole came up for hearing. In those cases that came up just after the judge had eaten a meal (in the morning after breakfast, in the afternoon after lunch, and in the evening after tea), the judge was much more lenient. However, cases heard towards the end of the session when judges had not eaten showed judges were much harsher in their verdicts.

Researchers Danziger, Levav, and Avnaim-Pesso “found that the probability of a favorable decision drops from about 65% to almost 0% from the first ruling to the last ruling within each session and that the rate of favorable rulings returns to 65% in a session following a food break.”

A finite amount of mental energy

There was much debate after the research on judges was published. Some findings said that the order of cases affected the results and that more complex cases or those where a lawyer did not represent the defendant came up for hearings later in a session. The social sciences require one to be extra careful in coming to conclusions.

However, the original hypothesis has evidence that, in large part, what seemed to be happening is that the judges suffered from “decision fatigue.” Just as our muscles get tired after too much exercise, our brains get tired after working for some time. The decisions we make depend very much on how fresh or tired our brains are.

While some might say that this is obvious, recent experiments have shown a physical basis behind decision fatigue. Professor Roy F. Baumeister and his colleagues showed that mental activity such as self-control relies on glucose being used in the brain as an energy source:“Acts of self-control reduced blood glucose levels

  1. “Acts of self-control reduced blood glucose levels
  2. Low levels of blood glucose after an initial self-control task predicted poor performance on a subsequent self-control
  3. Initial acts of self-control impaired performance on subsequent self-control tasks, but consuming a glucose drink eliminated these impairments.
  4. Self-control requires a certain amount of glucose to operate unimpaired.
  5. A single act of self-control causes glucose to drop below optimal levels, thereby impairing subsequent attempts at self-control.”

Further experiments found that the brain’s overall use of energy remains the same but that certain activities such as self-control cause activity to increase in some parts of the brain and reduce in others. When tired, the brain works more for short-term rewards and finds it difficult to make decisions for the longer term.

So what do we do?

Understanding the above research, psychologists suggest that when tired, we “do nothing.” The psychologists suggest avoiding major decisions when tired and postponing the task. This may be obvious, but how often have we ignored our mental states, become angry or unkind, and rushed into a decision? Professor Baumeister says that “the best decision-makers are the ones who know when not to trust themselves.”

While brain fatigue can be temporarily reversed by taking in some sugars (glucose), this provides only a short spike, after which the brain gets into an even worse state of fatigue. The suggestion is to get a steady supply of glucose throughout the day. This is obtained from eating proteins and nutritious foods in small quantities spaced out through the day. We are so used to two or three big meals a day that this is not easy to do. However, the science seems to say it is the more efficient way and that it results in us making better choices. Good luck with the decision you make!

© Kaikhushru Taraporevala