Manipulating articulatory demands in non-word repetition: A ‘late-8’ non-word repetition task

Abstract

The purpose of this paper was to examine the psychometric properties of a non-word repetition task (NRT), the Late-8 Non-word Repetition Task (L8NRT). This task was designed similarly to the NRT, but contains only Late-8 consonants to increase articulatory demands and avoid ceiling effects in studies with adolescents and adults. Thirty college students were administered the Woodcock Reading Mastery Tests-Revised/Normative Update WRMT-RNU, L8NRT and NRT. Results showed that inter- and intra-rater reliability of the L8NRT were high; split-half reliability was significant and comparable to that of the NRT. Average L8NRT scores were significantly lower than NRT scores overall and at all non-word lengths but the shortest (1 syllable). Both measures correlated significantly, at similar levels, with Total WRMT-RNU score. We conclude that the psychometric properties of the L8NRT were acceptable, but an error analysis suggested ways in which the task might be improved to better control perceptual demands and articulatory feature overlap.

Consonant Age-of-Acquisition Effects in Nonword Repetition Are Not Articulatory in Nature

“…The stimuli were used in an NWR task and two other tasks (auditory lexical decision and nonword reading) that require minimal to no phonological short-term memory. The two tasks were selected to rule out potential confounds to the CAoA effect (Moore et al, 2010). Auditory lexical decision was selected because it eliminates overt articulatory demands; nonword reading was selected because it eliminates auditory-perceptual demands.…”

“…The "soft g" sound (/ʒ/, as in beige and measure) in Shriberg and Kwiatkowski's Late-8 group is difficult to represent in orthographic form and does not occur in the initial position of English words, so it was excluded from the set of late-developing phonemes used in this study. Consonants for the early group were selected from Shriberg and Kwiatkowski's Early-8 and Middle-8 groups in order for the E7 group to be more closely matched in articulatoryfeature distribution to the L7 group, because featural differences were reported as a potential confound in previous work (Moore et al, 2010). The end result was an E7 group comprising the phonemes /m/, /n/, /p/, /d/, /t/, /f/, and /v/ and an L7 group comprising the phonemes /s/, /z/, /l/, /r/, /ʃ/, /θ/, and /ð/.…”

“…Consonant acquisition ranges from 3 to 9 years of age (using a 90% level-of-acquisition criterion), with phonemes such as /m/, /n/, and /p/ typically acquired by age 3 years and phonemes such as /s/, /z/, and /r/ acquired by age 7 years or later (Smit, Hand, Freilinger, Bernthal, & Bird, 1990). Moore, Tompkins, and Dollaghan (2010) explored the use of this CAoA manipulation with the goal of increasing task difficulty and thus avoiding ceiling effects when administering NWR to adolescents and adults. CAoA has been associated with articulatory complexitythat is, the motoric demands involved in speech sound production (e.g., Kent, 1992;Stokes & Surendran, 2005).…”

“…CAoA has been associated with articulatory complexitythat is, the motoric demands involved in speech sound production (e.g., Kent, 1992;Stokes & Surendran, 2005). The original motivation for use of the experimental manipulation by Moore et al (2010), therefore, was to increase the articulatory complexity of the stimuli. They reasoned that this could in turn influence short-term-memory performance.…”

“…Although the results of Moore et al (2010) achieved the goal of developing a more challenging NWR task, there are several reasons they could be regarded as unexpected. For instance, the effect was observed in a sample of native English-speaking college students who were highly skilled in the production of English phonemes, so it might be expected that developmental effects of consonant articulation would be negligible after so many years of speech-production practice.…”