Learning Simple and Complex Second Language Rules Under Implicit, Incidental, Rule-Search, and Instructed Conditions

Abstract

This study examines the generalizability of claims by Reber (1989, 1993) about the implicit learning of artificial grammars to the context of adult second language acquisition (SLA). In the field of SLA Krashen (1981, 1982, 1985, 1994) has made claims parallel to those of Reber regarding the differential effectiveness of conscious learning of rules and unconscious incidental acquisition of rules. Specifically addressed are Reber's and Krashen's claims that (a) implicit learning is more effective than explicit learning when the stimulus domain is complex, and (b) explicit learning of simple and complex stimulus domains is possible if the underlying rules are made salient. One hundred four adult learners of English as a second language were randomly assigned to implicit, incidental, rule-search, or instructed computerized training conditions. Speed and accuracy of judgments of novel tokens of easy and hard rule sentence types presented during training were used as dependent measures. Results do not support the first of Reber's and Krashen's claims but do support the second. Implicit learners do not outperform other learners on complex rules, but instructed learners outperform all others in learning simple rules. Analyses of the effect of sentence type and grammaticality on learning suggest a transfer-appropriate processing account of the relationship among consciousness, rule awareness, training, and transfer task performance.