Acquisition of English Dental Fricatives by Pakistani Learners

This paper is based on a study of the acquisition of dental fricatives by advanced Pakistani learners of English. The results are analyzed in light of predictions of the speech learning model (SLM: Flege 1995) using Optimality Theory (Prince & Smolensky 2004). In Pakistani English, dental fricatives [θ ð] are substituted with dental stops [t̪ d̪]. The current study aims to find out if Pakistani learners, after having acquired Pakistani English, can acquire British English dental fricatives at advanced level. Perception and production experiments were conducted with a group of 30 advanced Pakistani learners of English who, after acquiring Pakistani English (which substitutes dental fricatives with dental stops), were taught British English. The perception test was based on an identification task, a 3-alternative forced choice task and an AX discrimination task. In the production task, they were asked to produce the words ‘thieve’ and ‘these’ each three times along with some other distracters. The productions were evaluated by four native speakers of English on a Likert scale ranging from 5 to 1. The productions were also analyzed acoustically. The results show that the learners perceive English dental fricatives as labial fricatives [f v] but they can discriminate them from the L1 stops [t̪ d̪]. However, acoustic analysis of the productions indicates that the learners produce English dental fricatives as dental stops [t̪ d̪]. This asymmetry between perception and production poses a challenge for the speech learning model which predicts a correspondence between perception and production. The findings of the study point out that the speech learning model should account for the phonological behaviour of L2 learners and the phonology-phonetics interface which the model lacks.