Word-effect variables in speeded-naming-task: Lexical and sub-lexical effects on reaction time and response duration in single-word-reading in an opaque orthography

The study assessed the effects of word characteristics on monosyllabic word naming in English. 30 participants completed a speeded-word-naming task alongside two other tasks measuring word and non-word reading accuracy and fluency, and phonological awareness (TOWRE and Spoonerisms respectively). Responses were recorded (via the DMDX application) and reaction times (RT) and response durations (RD) were extracted by hand (using CheckVocal) and analysed. Multi-Level mixed-effects analyses indicated significant main effects on RT of word naming were: frequency and regularity. These findings were in line with previous research. The significant main effects on RD of word naming were: word frequency; item length; the orthographic similarity of words to other words; and bigram mean. Importantly, the study is the first of its kind to measure RD in word naming, in an opaque orthography. Interpretations of the results are discussed, including the possibility that the findings support a cascaded model of speech production, and suggest sub-lexical frequencies beyond the syllable. The double-deficit hypothesis of dyslexia is challenged, with RD findings suggesting that the factors influencing phonological awareness also influence rapid automatised naming (RAN). Limitations of the study and suggestions for future research are discussed