A moderate financial incentive can increase effort, but not intelligence test performance in adult volunteers

A new paper-and-pencil test of spatial visualization was constructed from the figures used in the chronometric study of Shepard and Metzler (1971). In large samples, the new test displayed substantial internal consistency (Kuder-Richardson 20 = .88), a test-retest reliability (.83), and consistent sex differences over the entire range of ages investigated. Correlations with other measures indicated strong association with tests of spatial visualization and virtually no association with tests of verbal ability.