The influence of age and verb transitivity on written sentence production.

In this paper we explore the influences of normal ageing and verb transitivity on sentence production. The underlying aim is to provide a foundation for further research on sentence production in Alzheimer's disease (AD). We used a computer-based written sentence production task, designed to elicit intransitive, monotransitive and ditransitive sentences. Data was collected using keystroke logging, a technique to capture the entire typing process. Data of ninety healthy elderly was analysed focusing on the following writing process variables: time on task, production time and pause times. Results show that age influences time on task, pause time before sentences and within words. Verb transitivity influences time on task, production time and pause time between words. For pause time before sentences and between words, an interaction effect between age and verb transitivity was found as well. These results indicate that a follow-up study with AD patients should not attribute a slowdown in one of these variables to the disease in its entirety but should instead be compared with the slowdown in age-matched healthy peers.