In 2024 Oxford University Press chose “brain rot” as its Word of the Year: the foggy, scattered feeling after hours of low-effort content. It is a vivid phrase. What does the research behind it actually say?
The review
In 2025, Psychological Bulletin published a systematic review and meta-analysis of short-form video use (the short clips on apps such as TikTok and Instagram Reels). It pooled 71 studies with 98,299 participants.
71
studies
98,299
people
r = −.34
use and thinking
What it found
- Thinking. More use went with poorer cognition overall (r = −.34). The links were strongest for attention (−.38) and inhibitory control, the ability to stop yourself (−.41).
- Mood. A weaker link with poorer mental health (r = −.21), strongest for stress (−.34) and anxiety (−.33).
- No link with body image or self-esteem.
- The pattern held for young people and adults and across platforms.
r runs from −1 to 1. Zero means no link; a negative number means that as one goes up the other tends to go down. −.34 is a moderate link.
What it does not say
A link is not a cause. Many studies in this area measure people once, which cannot show which came first. People who already find it hard to focus may watch more short video, or something else may drive both. The review cannot settle that.
So “brain rot” is a good name for a feeling, but the science does not show that short video rots anything. It shows that, across many studies, the two tend to go together.
A cheap experiment
You do not need the science to be settled to test it on yourself. Take the short-video apps out of reach for two weeks. Notice whether it is easier to read, to finish a task, to stay with a thought. If nothing changes, you have lost very little. If something does, you have learned it from the one source that counts, your own life.
Reference
- Feeds, feelings, and focus: A systematic review and meta-analysis examining the cognitive and mental health correlates of short-form video use. Psychological Bulletin, 151(9), 1125–1146 (2025). doi:10.1037/bul0000498