Onset entropy matters: Letter-to-phoneme mappings in seven languages

Alphabetic orthographies vary in the (in)consistency of the relations between spelling and sound patterns. In transparent orthographies, like Italian, the pronunciation can be predicted from the spelling, in contrast to opaque orthographies such as English, where spelling–sound correspondences are often inconsistent. The pronunciation of English vowel letters is in particular very ambiguous. In this paper, we provide a cross-linguistic investigation of orthographic transparency at the word-initial letter–phoneme level, resulting in ranked metrics for the seven languages investigated- Dutch, English, French, German, Hungarian, Italian, and Portuguese, expressed as entropy values. We focus on the contributions of vowels and consonants towards the overall orthographic transparency and provide evidence that deviations from consistent word-initial 1:1 mappings between letters and phonemes influence reaction times in naming tasks. Implications for theories of visual word recognition and speech production will be discussed