— Cognitive concept
Performance IQ
The cognitive ability index measuring spatial, perceptual, and non-verbal reasoning.
Performance IQ (PIQ) is the non-verbal counterpart to verbal IQ in older Wechsler test batteries. It measures spatial reasoning, perceptual organisation, and visual-motor problem-solving — abilities that don't depend on language.
What performance IQ measures
Classic performance IQ subtests included:
- Block design — reproducing abstract patterns with coloured blocks
- Picture completion — identifying missing details in images
- Picture arrangement — sequencing scenes to tell a story
- Object assembly — completing visual puzzles
- Digit symbol coding — speed of symbol-symbol pairing
Why it was created
Performance IQ was developed partly to allow IQ testing of people with limited English (or English literacy). The non-verbal nature of the tasks reduced bias from language background.
Modern equivalents
The verbal/performance split was retired in WAIS-IV (2008) and replaced with four indices that measure cognition more granularly: verbal comprehension, perceptual reasoning, working memory, and processing speed. "Performance IQ" as a single index is no longer reported on current Wechsler tests.
How Core Brain measures these abilities
Core Brain measures the abilities historically captured by Performance IQ across three of its six axes: spatial reasoning, pattern recognition, and abstract matrix reasoning. You see your score on each axis separately rather than as a single composite.
Related concepts
- Fluid Intelligence
- Crystallised Intelligence
- The g-factor (general intelligence)
- The Flynn Effect
- Verbal IQ