RT Journal Article
SR Electronic
T1 Healthy Aging and Sentence Production: Disrupted Lexical Access in the Context of Intact Syntactic Planning
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 327304
DO 10.1101/327304
A1 Sophie M. Hardy
A1 Katrien Segaert
A1 Linda Wheeldon
YR 2018
UL http://biorxiv.org/content/early/2018/10/10/327304.abstract
AB Fluent sentence production requires rapid syntax generation and word retrieval. We investigated how healthy aging affects these processes in two timed picture description tasks. In Experiment 1, young and older adults produced a syntactically related or unrelated prime prior to a target sentence (e.g., “the bell and the glove move up”). Both groups displayed significant facilitatory effects of priming on sentence onset latencies. In Experiment 2, participants produced sentences with initial coordinate or simple noun phrases (e.g., “the owl and the car move above the harp” / “the owl moves above the car and the harp”). On half the trials, the second picture (car) was previewed; critically, this previewed picture only fell within the initial phrase in the coordinate condition. Without preview, both age groups were slower to initiate sentences with larger coordinate phrases, suggesting a similar phrasal planning scope. However, age group differences did emerge in the preview conditions. Young adults displayed speed benefits of preview both within and outside the initial phrase. Whereas, older adults only displayed speed preview benefits within the initial phrase, and preview outside the initial phrase caused them to become significantly more error-prone. Thus, while syntactic planning scope appears unaffected by age, older adults do appear to encounter problems with managing the activation and integration of lexical items into syntactic structures. Taken together, our findings indicate that healthy aging disrupts the lexical, but not the syntactic, processes involved in sentence generation.