Science once 'proved' that being happy makes you worse at learning, but it turns out the researchers just forgot that people get better with practice.
April 15, 2026
Original Paper
Practice Effects Confound the Emotion–Performance Link in Self-Regulated Learning: A Reanalysis of Lin et al. (2026)
PsyArXiv · weu9m_v1
The Takeaway
A famous study once claimed that positive emotions actually hindered performance in certain types of learning. However, a new reanalysis shows this was just a massive statistical error. The original researchers didn't account for 'practice effects'—the simple fact that people naturally improve at a task the more they do it. When you control for that, the supposed negative link between happiness and performance completely disappears. It’s a perfect example of how easily a 'surprising' scientific discovery can just be a math mistake. For us, it’s a reminder that being in a good mood is probably still the best way to get things done.
From the abstract
Lin et al. (*Journal of Educational Psychology*, 2026) proposed a computational model of the dynamic interplay between goal setting, performance, and emotions in self-regulated learning. In a repetitive math task (Study 1), they reported that positive emotions predicted lower subsequent performance, interpreting this via the coasting hypothesis. We argue that this finding may instead reflect a temporal confound: in a repetitive task, performance improves due to practice while emotional engagemen