Sort cards by a hidden rule that changes without warning. Discover the rule through feedback and adapt quickly — a digital variant of the Wisconsin Card Sorting Test (Berg, 1948).
1. Four reference cards are displayed at the top — each with a unique color, shape, and number.
2. A test card appears in the center. Click the reference card that matches it by the hidden rule.
3. Use feedback (correct / wrong) to deduce the rule — color, shape, or number of symbols.
4. Adapt! The rule changes silently after several correct sorts. You must notice and shift strategies.
The key challenge is perseveration — continuing to sort by the old rule after it has changed. The WCST measures this in clinical neuropsychology.
Each card has a unique color, shape, and number — one rule always gives a clear match.