Turm von London

Tower of London (Shallice, 1982) is the standard executive planning task in clinical neuropsychology.

Three pegs hold colored balls. You must reach a goal configuration in a minimum number of moves.

Solving optimally requires looking ahead 3+ moves before acting — pure planning load.

Performance differentiates frontal-lobe injury from healthy controls more reliably than almost any other task.

Each test is constructed using Item Response Theory (IRT) and Classical Test Theory (CTT) to ensure reliable measurement of knowledge and ability across different difficulty levels.

Questions undergo rigorous review including difficulty calibration, discrimination analysis, and distractor effectiveness evaluation to maintain high assessment quality.

1. Look at the goal configuration on the left.
2. Tap a peg to pick up its top ball, then tap another peg to drop it.
3. Plan your full sequence before moving. Trial-and-error costs efficiency.
4. Each puzzle has a known minimum — your score reflects how close you get.