Latent semantic analysis: A new method to measure prose recall

Abstract

The aim of this study was to compare traditional methods of scoring theLogical Memory test of the Wechsler Memory Scale-III with a new method basedon Latent Semantic Analysis (LSA). LSA represents texts as vectors in a high-dimensionalsemantic space and the similarity of any two texts is measured by the cosineof the angle between their respective vectors. The Logical Memory test wasadministered to a sample of 72 elderly individuals, 14 of whom were classifiedas cognitively impaired by the Mini-Mental State Examination (MMSE). The resultsshowed that LSA was at least as valid and sensitive as traditional measures.Partial correlations between prose recall measures and measures of cognitivefunction indicated that LSA explained all the relationship between LogicalMemory and general cognitive function. This suggests that LSA may serve asan improved measure of prose recall.