Correlations between Semantic Priming, Word Recognition and Gray Matter Density

Introduction Semantic priming tasks provide a sensitive measure of word recognition and word meaning access. While functional MRI studies of semantic priming suggest involvement of a fronto-temporal network, regional gray matter volume associated with semantic priming in healthy older adults has not been considered. There is still some debate in the literature regarding whether semantic priming and lexical access varies with age, with reports suggesting that word recognition may slow but semantic priming may be unchanged or abnormally large. [1]. A comparison of repetition and semantic priming reveal distinct regions of activation [2], being largely fronto-temporal for semantic priming. Most neuroimaging studies of priming have employed a word pair paradigm that involves automatic spreading activation but also encourages both pre-lexical expectancy generation and postlexical semantic checking. List priming provides a means of reducing controlled processing influences as the relationship between primes and targets is less discernible to the participant. This study examines the individual differences in regional gray matter (GM) volume associated with priming in healthy older adults employing a list priming paradigm.