Perceptual development of a new phoneme contrast by adult and 12-year-old listeners

How does the perception of a new phoneme contrast develop? Are differences found across age groups? In answering these questions, we use two alternative hypotheses: i) Acquired Distinctiveness: before learning, differences between and within phoneme categories are relatively hard to discriminate. Through training, the phoneme boundary is learned. ii) Acquired Similarity: before learning, differences between and within phoneme categories are relatively well discriminated. Due to training, only the phoneme boundary remains discriminable. We will discuss two perception experiments. In experiment I, Dutch adults learned the British-English pseudowords ‘thif ’ and ‘sif ’ (the first consonant in ‘thif’, /θ/, is not a phoneme of Dutch). Between pretest and posttest with materials from one speaker, participants were trained with speech from five other speakers. This forced them to form abstract phoneme categories. The results show that trained listeners seemed to perform better than control listeners in the posttest. However, in general, the control group, who received no training, was difficult to distinguish from the trained listeners. In experiment II, a small group of 12-year-old Dutch children was tested on the same contrast. They received a restricted amount of training. With respect to our question of how the perception of a new phoneme contrasts develops, it appeared that similar learning paths were used by both age groups: discrimination levels increased as a result of learning