Problem solving ability in aging and dementia: normative data on a non-verbal test.

A non-verbal problem solving task, viz. a simplified version of Shallice's London Towers Test, was given to 131 normal subjects to obtain normative data relating to age, education and sex. The test was built up in its easiest possible feature in order to be administrable also to demented patients, therefore possibly becoming part of the neuropsychological diagnostic procedures of the demential syndromes. Although this version of the test proved to be very easy and therefore likely to yield a statistically treatable wide distribution of scores in demented patients, the age-related decline of performance in normals was apparent. Education and sex showed no significant influence on the test-performance. With correction of the raw scores for age and with knowledge of the distribution of scores in the normal population, this test is now ready to assess the normality of the scores of a new subject according to his age, giving information on this otherwise still uncovered sector of cognitive abilities.