Exploring input processing in the classroom: An experimental comparison of processing instruction and enriched input

The research reported here tests the claim made in the Input Processing approach to second language (L2) acquisition that interpreting the meaning of language form is essential for learning. This claim has been put forward as an underlying part of the pedagogical package known as Processing Instruction (PI) (VanPatten, 1996, 2002a, 2004). Two experiments compared PI with a type of "Enriched Input" (operationalized as the same brief grammar explanation as in PI, followed by equal numbers of exemplars of the target features but where attention to the forms or their meanings was not necessary to the task). In a pretest, posttest, delayed posttest design, first language (L1) English speakers' oral and written interpretation and production of L2 French verb inflections for tense, number, and person were examined. The impact of proficiency level on the necessity of making integrated form-meaning connections was also examined, by carrying out the same experiment with two groups at different levels of proficiency. Results from both experiments were generally compatible with the Input Processing claim earlier, although contextual- and measurement-dependent factors affected the results from the writing and oral measures in the second experiment.