The Role of Perception in Differential Substitution

Abstract This article examines differential substitution of the L2 English voiceless interdental fricative, [θ]. The L1s investigated in this study—European French, Québec French, and Japanese—have been reported to substitute [s], [t], and [s] respectively in production. Two main hypotheses are explored: 1) Transfer is perceptually based; 2) Substitution involves an assessment of non-contrastive in addition to contrastive features. Results of an AXB task show that advanced learners are unable to perceive certain non-contrastive distinctions; however, unlike Japanese listeners, French listeners do perceive Strident and Mellow, features which are non-contrastive in their L1. Results indicate a clear perceptual basis for the Japanese substitute. The difference between Québec and European French is less clear; however, there is a trend which suggests a perceptual basis for the European French substitute. Another finding is that confusion of [f] and [θ] is greater for French than it is for Japanese listeners. It is proposed that the composition of the L1 phonetic inventory influences which features listeners attend to during perception.