Stereotypical bias
Memory that drifts toward stereotypes, so we recall details that fit what we expect of a group and forget or change details that do not.
The evidence is mixed: many studies find that people remember stereotype-breaking details better, and the pull toward stereotypes shows up mostly when memory is hazy and people fill in the gaps.
In everyday life
After a meeting, you recall the older colleague struggling with the video software, though it was actually the young intern who needed help.
You remember the librarian you met at a party as quiet and bookish, but friends remind you she told the loudest stories of the night.
Why your mind does this
We could never store the details of every person and event we meet, so the brain boils experience down into categories and rough summaries. These let us make fast guesses about new people and situations with little effort. Holding on to bad experiences, while letting old pain soften, also helped us learn from danger without being crushed by it.
Its family, in 30 seconds: Generalities
How to spot it
Ask whether the details you remember about someone match what they really did or just what you expected of people like them.
How to counter it
Write down specific facts about people right after a meeting or event, before your expectations fill in the gaps.