Tower of London
Tower of London, introduced by Shallice (1982) and standardized in TOL-DX by Culbertson & Zillmer, measures prefrontal planning ability. Widely used in ADHD and executive-function research.
Intermediate: 8 problems, up to 6-step.
The top panel is the GOAL; the bottom is CURRENT. Move balls in the current panel to match the goal using as few moves as possible. Rules: (1) one ball at a time; (2) peg capacity must not be exceeded. Click a peg to pick up the top ball; click another to place it.
History
No training records yet
References: Shallice (1982); Culbertson & Zillmer (1998, 2005).
Tower of London · scientific basis
Tower of London was introduced by Tim Shallice (1982) to study planning deficits after frontal-lobe damage. Culbertson & Zillmer (1998/2005) developed the clinical TOL-DX standardization (MHS).
Expert-mode parameters
These are the standard parameters from the canonical paradigm (used by the "Expert" difficulty).
| Parameter | Standard value | Source |
|---|---|---|
| Problem count | 10 (TOL-DX) | Culbertson & Zillmer 2005 |
| Minimum moves | 3-7 (graded) | Culbertson & Zillmer 2005 |
| Time limit | 60 s per problem | Shallice 1982 |
| Apparatus | 2 towers, 3 pegs each, 3 colored balls | TOL-DX standard |
Healthy-population norms (by age)
Primary outcomes are Total Correct (problems out of 10 solved at minimum-move count) and Total Excess Moves. Accuracy = Total Correct / 10. Accuracy Excellent = mean + 1 SD. Based on Culbertson & Zillmer 1998 TOL-DX standardization sample (n≈400, ages 7-80). Assessment mode matches the band to your actual age.
| Age band | Accuracy Excellent | Accuracy Mean | Excess Moves Mean | Evidence |
|---|---|---|---|---|
| 8-9 | ~33% | ~20% | ~60 | moderate |
| 10-11 | ~52% | ~35% | ~40 | moderate |
| 12-13 | ~63% | ~45% | ~34 | moderate |
| 14-15 | ~71% | ~52% | ~30 | moderate |
| 16-17 | ~77% | ~58% | ~26 | moderate |
| 18-24 | ~82% | ~62% | ~24 | moderate-strong |
| 25-34 | ~84% | ~64% | ~23 | moderate-strong |
| 35-44 | ~83% | ~63% | ~23 | moderate-strong |
| 45-54 | ~80% | ~60% | ~25 | moderate-strong |
| 55-64 | ~76% | ~55% | ~28 | moderate |
| 65+ | ~70% | ~48% | ~33 | moderate-weak |
Standard output metrics
- ·Total Correct — Problems solved at minimum-move count
- ·Total Moves — Sum across problems (excess)
- ·Initiation Time — Planning time before first move
- ·Execution Time — First-move to completion
- ·Rule Violations — Peg-capacity violations
Citations
- Shallice, T. (1982). Specific impairments of planning. Philos Trans R Soc Lond B Biol Sci, 298(1089), 199-209. DOI
- Culbertson, W. C., & Zillmer, E. A. (1998). The construct validity of the Tower of London-DX. Assessment, 5(3), 215-226. DOI
- Culbertson, W. C., & Zillmer, E. A. (2005). Tower of London—Drexel University (TOL-DX) Technical Manual (2nd ed.). MHS. DOI
- Berg, W. K., & Byrd, D. L. (2002). The Tower of London spatial problem-solving task. J Clin Exp Neuropsychol, 24(5), 586-604. mhs.com
All reference ranges come from published peer-reviewed literature. For personal training reference only — not a medical diagnosis. Full methodology: docs/PARADIGMS.md.
This tool is for educational and entertainment purposes only and does not constitute medical advice or a clinical diagnosis.