The effect of auditory input and voice familiarity on L2 listening comprehension
and the processing of grammatical forms: an eye–tracking study

Today’s learners have access to ample auditory pedagogical materials that come with wider speaker variability than traditional classroom materials. However, systematic experimental investigations of the effects of input modality and of voice familiarity on L2 syntax acquisition are sparse. This study examines the effects of auditory modality and training voice on the efficacy of Processing Instruction (PI), which has been demonstrated to facilitate improvement in both comprehension and production of novel grammatical forms (e.g.,VanPatten & Cadierno, 1993) more effectively than traditional drill practice. Previous research (Wong & Ito, 2018) showed that training with PI in the written modality on the French causative structure resulted in robust improvement in accuracy scores in a forced-choice picture selection task, and reduced L2 learners’ tendency to assign the role of agent to the first NP. The present study further investigates the effect of PI-training with auditory input and also tests the effect of voice familiarity on online L2 processing.

Two experiments used two voices (Experiment 1: female; Experiment 2: male) in a picture-selection eye-tracking task, and the same two voices for auditory PI-training. Participants listened to a sentence and had to choose between two scenes that exchanged the roles of two people performing an action. Eye movements were compared before and after PI-training with either the same or different voice than the voice used for the picture-selection task. A total of 114 L2 French learners from a 3rd-semester college French course participated in the experiments.

Both experiments confirmed a robust effect of auditory PI-training on picture-selection accuracy with an equivalent degree of improvement when compared with written PI-training. However, eye-movements showed that the timing of the shift to the correct picture occurred later when compared to written PI-training. The effect of voice familiarity was larger for the male voice, which produced shorter duration for the earlier grammatical cue but longer duration for the later grammatical cue to the target causative structure than the female voice. The findings suggest that auditory PI-training is equally effective as written PI-training. The consistency of input modality was not particularly beneficial to L2 learners, who may not allocate their limited L2 cognitive resource to the details of grammatical forms while processing auditory input for meaning. While hearing the same voice through the training and testing may generally facilitate the acquisition of target structures, the effect seems to depend on which part of speech conveys the salient grammatical cues.