In our fast-paced world, people are often advised to make snap decisions based on first impressions. However, a recent study suggests that taking time to “sleep on it” before making important choices may result in more thoughtful, balanced decisions.
Published on September 9 in the Journal of Experimental Psychology: General, a study led by Duke University researchers explores how first impressions affect decision-making and whether delaying judgment improves outcomes. The research offers valuable insights into the age-old debate of whether it’s better to start strong with a good first impression or finish well.
In the study, participants were asked to evaluate items from an imaginary garage sale. The items were presented in boxes, with some more valuable than others. The challenge was to estimate the total value of the boxes and choose which ones to “sell.” The twist: while the total value of the boxes was the same, the sequence in which valuable items appeared varied. Some boxes presented valuable items upfront, while others hid the gems in the middle or the bottom.
The results were telling. Participants who made immediate judgments were heavily influenced by the first few items they encountered—a cognitive bias known as “primacy bias.” They overestimated the value of boxes with treasures on top by about 10%, often forgetting key details about other items within the box.
Allie Sinclair, the lead author and now a postdoctoral fellow at the University of Pennsylvania, explained, “We found that people are strongly biased by first impressions. When valuable items appeared first, participants were more likely to select those boxes, even though the total value was the same as others.”
However, participants who delayed their decision until the next day were less likely to fall prey to this bias. Instead of favoring boxes that “started strong,” they made more rational choices, equally considering boxes with valuable items placed throughout.
“Sleeping on it led to more balanced decisions,” Sinclair noted. “People who took time were better at weighing all the items and weren’t overly swayed by what they saw first.”
Dr. Alison Adcock, the study’s senior author and a professor of psychiatry and behavioral sciences at Duke, added, “Judging from first impressions may be useful for quick decisions—like whether to keep watching a movie after the first scene. But for decisions with long-term consequences, such as hiring someone or deciding on a second date, taking more time often leads to better choices.”
The study highlights the importance of allowing the brain time to process information. Dr. Adcock elaborated, “Our brains consolidate and summarize experiences overnight, helping us make more informed choices the next day.”
This research was funded by a Duke Health Scholars Award and represents a significant contribution to our understanding of how the brain processes information and makes decisions. While trusting first impressions can be useful in the moment, the study suggests that in cases where long-term outcomes matter, the advice to “sleep on it” may be worth following.
As we continue to navigate a world filled with fast decisions, this study serves as a reminder that sometimes, taking a pause may lead to better choices in the end.