Frequency, not age of acquisition, affects Italian word naming

Abstract

The purpose of this study was to evaluate the claim that age of acquisition (AoA) and word frequency effects are reduced or nonexistent in languages that have very regular letter-to-sound mappings, like Italian. The first two experiments (Exp. 1, Exp. 2) showed that frequency variables affect reading aloud and lexical decision in Italian. Variables interpretable as pertaining to a semantic component, including AoA, affected lexical decision but not reading aloud. In Experiments 3 and 4, a measure of frequency—child written word frequency (ChFreq)—and AoA were manipulated. Reading performance was affected by word frequency but not by AoA (Exp. 3), whereas lexical decision was affected by both variables (Exp. 4). In Experiments 5 and 6, ChFreq and AoA were manipulated orthogonally. Only frequency affected reading aloud, with no main effect or interaction involving AoA (Exp. 5). The effects of AoA and frequency interacted in Experiment 6 for lexical decision due to a larger effect of AoA for low frequency words than high frequency words. These results show that in languages with a transparent orthography word frequency may affect reading aloud in the absence of an effect of AoA because Italian readers employ lexical nonsemantic reading aloud. The effect of child written frequency points to the efficiency of the mappings between those orthographic and phonological word forms that were frequently encountered when learning to read.

Acknowledgements

The authors wish to thank Laura Menenti, Jim Flege, Stefania Marcolini, Despina Paizi, and Pierluigi Zoccolotti for valuable comments on the manuscript. Cristina Burani and Laura Barca are members of a Marie Curie Research and Training Network: Language and Brain (RTN:LAB) funded by the European Commission (MRTN-CT-2004-512141) as part of its Sixth Framework Programme.

Notes

¹There is, however, some uncertainty as to whether the differences reported in previous reading aloud studies were due to differences in AoA or frequency. Zevin and Seidenberg (2002) report reanalyses of data from both factorial and multiple regression studies, which indicate that AoA effects may have been due to confounds with frequency differences.

²The first part of the Marconi et al.'s (1993) frequency count is similar to the frequency measure provided by Carroll, Davies, and Richman (1971) for American English for third to ninth graders, and by Lété, Sprenger-Charolles, and Colé (2004) for French for first to fifth graders. The second part of the Marconi et al.'s frequency count is closer to frequency counts based mainly on child-written production such as that of Rinsland (1945) and Santiago, Justicia, Palma, Huertas, and Gutiérrez (1996), for English and Spanish, respectively.

³These cases involve the letters c and g, pronounced as /k/ or , or as /g/ or , respectively, depending on the following letter. The two cases whose correct translation necessitates a three-letter context involve the orthographic sequence of two consonants: sc and gl, translated with either two phonemes (/sk/ and /gl/ respectively), or with a single phoneme ( and respectively) depending on the following letter. The double letters cc and gg are also translated into two different geminate phonemes on the basis of the following letter.

⁴The stimuli of one set (high frequency–early acquired words) included less contextual rules than stimuli in the other sets. However, no effects of rule contextuality have been reported for high frequency words (Burani et al., 2006).