To be semantically-impaired or to be syntactically-impaired: Linguistic patterns in Chinese-speaking persons with or without dementia

Abstract Linguistic patterns of persons with Alzheimer's disease (AD) have been characterized by semantic-conceptual impairment vs. structural impairment. Few studies, however, examined the predictive power of semantic or structural attributes on the severity of dementia. The current paper investigates semantic and syntactic aspects in picture description by Chinese-speaking persons. Speech samples were collected from 30 AD patients and 32 elderly control participants. Conceptual-semantic and syntactic knowledge or errors were analyzed. Results indicated that persons with AD remained structurally rich with similar syntactic structure as the controls, though they conveyed less information and made more semantic errors. Multiple regression analyses on the linguistic attributes and the severity of dementia revealed that one semantic attribute (i.e. Objects) and two syntactic attributes (i.e. Conjoined sentences and Unintelligible sentences) could reliably predict the severity of dementia for Chinese-speaking population in Taiwan.