Everyone knows the popular adage “the night is advice”, which recommends waiting until the next day before making a decision. But is it really effective? A new scientific study provides the answer.
How many times have we hesitated before making a choice or an important decision? No matter how much we turned the situation around, asking for advice here and there, it was impossible to decide. Most of the time, it is often advisable to take a step back and carefully weigh the pros and cons. So, we have all heard, at least once in our lives, the expression “The night gives advice”.
This means that you have to leave yourself a night before making an important decision, because the night's sleep becomes a break that allows you to take the necessary distance from events before acting accordingly. In the morning, we know what to do. But is this adage true?
According to a new study published in September 2024, carried out by a team of researchers from Duke University (United States), sleep helps us make more rational and informed decisions, and not let ourselves be influenced by a misleading first impression.
To reach this conclusion, the researchers asked participants to take part in a garage sale game, by searching virtual boxes which contained objects, before estimating their value. Some items weren't worth much, while others were. In some boxes, valuables were on top, so they could be immediately spotted when unpacked.
After rummaging through several boxes, participants were asked to choose their favorite box and earn a cash reward equivalent to the value of the items in the box. It turns out that the vast majority tended to select their boxes not based on their overall contents, but rather based on the first items that appeared. In other words, these participants were influenced by the early information they encountered and did not consider later information in their decision. On the other hand, after having had a night's sleep, they made more rational choices, taking into account the whole box, without being influenced by the position of the objects inside.
For what ? “When it comes to forming an overall opinion about something, it turns out that we are unduly influenced by the first information we encounter, even when new facts emerge”explain the researchers. “This is an example of a psychological phenomenon called primacy bias”. On the other hand, by letting a certain amount of time pass, we no longer fall into the trap.
Previous experiments showed that participants could solve problems much more easily after sleeping, including those they were stuck on. They understood the underlying structures of events, managed to make more subtle associations, etc. Conversely, lack of sleep greatly reduces the ability to make informed decisions. You'll think about it the next time you spend the night working!
