Posted on behalf of Xavier Gutiérrez

Xavier Gutiérrez is an assistant professor of Applied Linguistics and Spanish at the University of Alberta in Canada. His latest article, published in Studies in Second Language Acquisition, published by Cambridge University Press, can be accessed today at no charge until October 12, 2013.

Researchers in the field of second language acquisition (SLA) have long been interested in finding out what type of mental representations of linguistic knowledge second language learners develop and how. In short, knowledge of language may be represented in two ways: as implicit, unconscious knowledge—the type usually involved in spontaneous language use such as casual conversations—or as explicit, conscious knowledge, which is involved in more controlled uses of language such as writing. Progress in this area has arguably been slow mainly due to challenges in obtaining valid and reliable measures of implicit and explicit knowledge.

One of the most popular instruments used in SLA to measure linguistic knowledge are grammaticality judgment tests (GJTs). GJTs typically consist of a number of grammatical and ungrammatical sentences, and learners are asked to indicate which ones are correct and which ones are not. Additionally, learners are sometimes asked to identify the error, correct it, and/or describe the grammatical rule violated in the sentence. In GJTs in which learners are only asked to determine the grammaticality of the sentences, there are still questions as to which type of knowledge the tests actually measure.

In recent years, several studies have used factor analysis to determine the validity of measures of implicit and explicit knowledge. Regarding GJTs, these studies have found that tests in which learners have time constraints to judge the sentences (i.e., timed GJTs) constitute measures of implicit knowledge, whereas tests without time limits (i.e., untimed GJTs) are measures of explicit knowledge. Additionally, some studies have noted that, in untimed GJTs, only ungrammatical sentences actually measure explicit knowledge. The study reported in this article takes this issue a step further and examines differences between both types of task stimuli (i.e., grammatical and ungrammatical sentences) in timed and untimed GJTs. The results of the study show that there are statistically significant differences between the learners’ responses to grammatical and ungrammatical sentences in both types of tests and that such differences can be interpreted as learners resorting to their implicit knowledge when judging grammatical sentences and to their explicit knowledge when judging ungrammatical ones. Furthermore, it was found that both time pressure and task stimulus have a significant effect on the learners’ performance on the GJTs. Given the popularity of GJTs in SLA, this study makes a potentially meaningful contribution to the debate on measures of implicit and explicit knowledge.