Consonant age of acquisition effects are robust in children's nonword repetition performance

Abstract

The underlying processes of nonword repetition (NWR) have been studied extensively in both typical and atypical development. Most of the research examining long-term memory effects on NWR has focused on lexical and sublexical variables that can only be computed relative to the lexicon of a specific language (e.g., phonotactic probability). Sublexical variables that can be defined without reference to the lexicon (e.g., consonant age of acquisition; CAoA) have received little attention, although recent work has shown a CAoA effect on NWR in young adults by measuring performance differences when the stimuli comprise consonants acquired later versus earlier in speech development. The purpose of this study was to identify whether this sublexical effect occurs earlier in development. Thirtyone typically developing first and second graders completed NWR, nonword reading, and auditory lexical decision tasks. Nonword accuracy and word nonword discriminability were consistently lower for items comprising later versus earlier acquired phonemes, even after controlling for vocabulary knowledge, but there were no differences in speed measures. Patterns of performance were similar to the CAoA effects observed in young adults from previous work. Results indicate that the sensitivity of NWR performance to these sublexical long-term memory effects occurs in childhood and reflects adultlike patterns of performance."