Poppelreuter-Ghent's Overlapping Figures Test: its sensitivity to age, and its clinical use.

This study aims to identify the cognitive variables involved in a task of visual recognition of meaningful and meaningless two-dimensional line-drawings of shapes; the Poppelreuter-Ghent Overlapping Figures Test. It was found that the performance of healthy controls was influenced by age and education, but not sex. Age and education adjusted norms are set forth. Meaningful patterns were better recognised than meaningless ones. Number of overlapping patterns, direction, and degree of rotation were among the other variables considered. Only the latter variable significantly influenced the difficulty of the task. The clinical use of this test was verified on clinical populations of patients affected by Alzheimer's disease and right or left hemisphere damage. Left hemisphere damaged patients did not show deficits. Alzheimer and right hemisphere damaged patients were impaired and the degree of rotation significantly influenced their performance. In conclusion, the Poppelreuter-Ghent's Test is a multicomponential task, the visuo-spatial components of which were shown to be the most important.