Effects of Lexical Priming on Priming Type and Presence of Distractors in Persons with Mild Cognitive Impairment

Objectives: The purpose of the study is to examine if the lexical priming effect is valid in persons with mild cognitive impairment (MCI). In addition, this study attempted to examine the correlation between working memory and sentence production ability for MCI and healthy adults (HA). Methods: Fifteen individuals with MCI and sixteen HA described action pictures in sentences following lexical (agent or theme) primes. Priming effect was analyzed in terms of priming type and presence of distractor. Results: 1) Persons with MCI did show significantly lower proportion of passive sentences compared to HA. Overall, the proportion of passives were significantly higher in the theme primed condition versus the agent primed condition. 2) The difference in the presence of distractor stimuli in the agent primed condition was significantly larger than in the theme primed condition. 3) It was observed that the better the working memory ability of MCI participants, the higher the production of active sentences when compared with passive sentences in the theme primed condition. Conclusion: Persons with MCI used word-driven information as a strategy of sentence production like HA did. In addition, MCI participants showed difficulty in production of complex structures such as passive sentences. In previous research, most of the studies examined the priming effect through structural priming tasks for HA and aphasia patients. The results of this study also showed the effect of lexical priming in persons with MCI, and the finding of lower production of passive sentences in persons with MCI compared to HA emphasized the linguistic deficits that may appear in individuals with MCI.