Language Analytic Ability, Print Exposure, Memory and Comprehension of Complex Syntax by Adult Native Speakers.

Nativist theories of language development assume that all native speakers of a particular language ultimately converge on (more or less) the same grammar, and argue that this is only possible because they are born with a genetic blueprint for language. However, a number of recent studies have found that there are, in fact, considerable individual differences in adult native speakers' grammatical attainment. In this study, we examine some possible reasons for these differences. We examine both learner internal cognitive factors (implicit and explicit memory for sequences, non-verbal working memory, and language analytic ability) as well as an experiential factor (print exposure). In contrast to many earlier studies which focused on the temporal aspects of language processing, we are interested in the extent to which individuals are able to use grammatical cues to extract meaning from complex sentences. To minimize the effect of performance factors, sentences remained on screen while participants responded to comprehension questions (thus easing working memory load) and participants were given as much time as they needed to respond. Our findings revealed large effects of language analytic ability and print exposure, and a much smaller effect of implicit learning. While the effect of implicit learning fits in well with current theories of language acquisition and processing, the first two findings do not. The strong relationship between print exposure and comprehension suggests that the ability to process complex syntax may depend on a particular type of language experience which is not available to all speakers. Finally, the effect of language analytic ability challenges the wide-held conviction that the ability to identify and explicitly reason about linguistic patterns is only relevant in adult second language learning.