The role of acoustic familiarity in the perception of L2 contrasts

Abstract

Difficulties in L2 perception are often attributed to assimilation of the L2 contrast by an L1 category or to interference by L1‐relevant acoustic cues [Iverson et al. ‘‘Phonetic training with acoustic cue manipulations: A comparison of methods for teaching English /r/‐/p/ to Japanese adults,’’ J. Acoust. Soc. Am. 118, 3267–3278 (2005)]. These approaches assume that cue weights change slowly over developmental time and are relatively constant for short time scales. An alternative view is that cue extraction and weighting are dependent on the overall familiarity of the current sound, with more familiar sounds facilitating more robust cue extraction and better discrimination [e.g., McFadden and Callaway, JEP:HPP, 25, 543 (1999)]. This hypothesis was tested with the perception of English sounds by Japanese adults. The Japanese listeners are insensitive to a cue (F3 onset) when it is part of (putatively unfamiliar) English /ra/ and /la/ sounds. The effect of familiarity was evaluated by fixing the range of F3 onsets and manipulating the rest of each sound in two ways: (1) by changing the transition durations to be more suitable for a moraic rhythm and (2) by changing the F1, F2, and amplitude trajectory to be more like the Japanese /r/. Discrimination improved markedly with the latter manipulation, suggesting that cue sensitivity is conditioned upon overall acoustic familiarity. [Work supported by NIH MH64445.]