Lexical decision reaction time study of reading Chinese in patients with mild Alzheimer’s disease and mild cognitive impairment / 中华神经科杂志

ABSTRACT

Objective To delineate the changes in pattern and time course of semantic and phonological processing during Chinese language cognition study in patients with mild Alzheimer’s disease (AD) and mild cognitive impairment (MCI). Methods Patients with mild AD(n=32)and MCI (n=39) as well as normal controls (NC, n=40) matched with age, gender, level of education were enrolled in the study. Subjects completed Chinese compound word decision task applying both short and long stimulus onset asynchrony (SOA). Semantic, homophonic, semihomophonic and unrelated primes preceded the real words as well as nonwords targets. Subjects were asked to judge whether the targets were real words or nonwords. The reaction time and accuracy were recorded for each response. Semantic and phonological priming effects were analyzed by comparing the related primes versus unrelated primes. Analyses of variance (ANOVA) and t-test were conducted for reaction time and accuracy respectively. Results The mean reaction times of mild AD and MCI groups were prolonged (411 ms and 234 ms) for all types of priming in contrast with NC(P