Tracking the emergence of the consonant bias in visual-word recognition: evidence with developing readers

PHOR-in-One: A multilingual lexical database with PHonological, ORthographic and PHonographic word similarity estimates in four languages

A large body of research seeking to explore how form affects lexical processing in bilinguals has suggested that orthographically similar translations (e.g., English-Portuguese "paper-papel") are responded to more quickly and accurately than words with little to no overlap (e.g., English-Portuguese "house-casa"). One of the most prominent algorithms to estimate orthographic similarity, the normalized Levenshtein distance (NLD), returns an index of the proportion of identical characters of two strings, and is an efficient and invaluable tool for the selection, manipulation, and control of verbal stimuli. Notwithstanding its many advantages for second-language research, the absence of a comparable measure for phonology has resulted in the adoption of different strategies to assess the degree of interlanguage phonological similarity across the literature, with profound implications for the interpretation of results on the relative role of orthographic and phonological similarity in bilingual lexical access. In the present work, we introduce PHOR-in-One, a multilingual lexical database with a set of phonological and orthographic NLD estimates for 6160 translation equivalents in American and British English, European Portuguese, German and Spanish in a total of 30,800 words. We also propose a new measure of phonographic NLD, a pooled index of orthographic and phonological similarity, particularly useful for researchers interested in controlling for and/or manipulating both estimates at once. PHOR-in-One includes a comprehensive characterization of its lexical entries, namely Part-of-Speech-dependent and independent frequency counts, number of letters and phonemes, and phonetic transcription. PHOR-in-One is thus a valuable tool to support bilingual and multilingual research.

Syllable effects in beginning and intermediate European-Portuguese readers: Evidence from a sandwich masked go/no-go lexical decision task

Reading is one of the most important milestones a child achieves throughout development. Above the letter level, the syllable has been shown to play a relevant role at early stages of visual word recognition in adult skilled readers. However, studies aiming to examine when, during reading acquisition, the syllable emerges as a functional sublexical unit are scarce, and the studies conducted so far have led to inconsistent results. In this work, beginning and intermediate European-Portuguese (EP) developing readers performed a sandwich masked lexical decision task in which CV (e.g., RU.MOR[rumour]) and CVC (e.g., CIS.NE[swan]) first-syllable EP words were preceded either by syllable congruent (e.g., rum.ba-RU.MOR, cis.ra-CIS.NE), syllable incongruent (e.g., rum.ba-RU.MOR, ci.ser-CIS.NE), unrelated (e.g., va.cra-RU.MOR, zar.vo-CIS.NE) pseudowords primes, or identity (e.g., ru.mour-RU.MOUR, cis.ne-CIS.NE) primes. Results showed reliable syllable effects only for intermediate readers and for CV and CVC words alike. Findings are discussed attending to current models of visual word recognition.

The role of letter features on the consonant-bias effect: Evidence from masked priming

Recent research has shown an advantage of consonants at early stages of visual word recognition (C-bias), although the locus of this effect remains elusive. Here we examine whether the C-bias is affected by the consonant letters' features. Skilled readers performed a masked priming lexical decision task in which target words containing only either consonants without any ascending/descending features (flat words, canino[canine]) or consonants with ascending/descending features (non-flat words, palito[toothpick]) were preceded by briefly (50 ms) presented primes that could preserve the same consonants of the targets (cenune-CANINO, pelute-PALITO), the same vowels of the targets (raxizo-CANINO, fajibo-PALITO), or, as controls, unrelated (ruxuze-CANINO, fejube-PALITO) and identity primes (canino-CANINO, palito-PALITO). The case in which prime-target pairs were presented was also manipulated (lower-upper vs. upper-lower). Results showed that in both case conditions flat words were recognized faster than non-flat words. Evidence for the C-bias was observed both for flat and non-flat words in the lower-upper condition, in which a vowel inhibitory priming effect was also observed for non-flat words. In the upper-lower condition, however, the C-bias was restricted to flat words. These findings suggest that letter features play a role in the C-bias and ask for amendments in current models of visual word recognition.

Masked identity priming reflects an encoding advantage in developing readers

The masked priming technique is widely used to explore the early moments of letter and word identification. Although this technique is increasingly used in experiments with young readers, the mechanism in play during masked priming with early readers has not yet been fully explored. We investigated the masked priming effects from a modeling perspective; we instantiated competing theories as data models (using Bayes factors) and as a computational model (diffusion model). We carried out a masked priming experiment using identity primes with second- and fourth-grade participants, and we analyzed the data through an evidence accumulation model lens. The priming effect manifests as a shift in the response time distribution, which in evidence accumulation models is accounted for by changes in the encoding process. We describe such changes as savings that have three features of theoretical importance. First, they are numerically very close to the stimulus onset asynchrony between primes and targets. Second, they remain relatively constant from second grade to fourth grade. Third, they seem to operate at the level of abstract orthographic representation because the priming effect occurs in both case-matched and case-mismatched pairs. These findings also have consequences for the practice of data transformation in developmental research; some patterns of data, when transformed, would produce spurious effects.

The impact of consonant–vowel transpositions on masked priming effects in Italian and English

There are now a number of reports in the literature that transposed letter (TL) priming effects emerge when two consonants are transposed (e.g., caniso-CASINO) but not when two vowels are transposed (e.g., cinaso-CASINO). In the present article, four masked priming lexical decision experiments, two in Italian and two in English, are reported in which TL priming effects involving the transposition of two adjacent consonants (e.g., atnenna-ANTENNA) were contrasted with those involving the transposition of a vowel and an adjacent consonant (e.g., anetnna-ANTENNA), a contrast not directly examined in the previous literature. In none of the experiments was there any indication that the priming effects were different sizes for the two types of transpositions, including Experiment 4 in which a sandwich priming paradigm was used. These results support the assumption of most orthographic coding models that the consonant–vowel status of the letters is not relevant to the nature of the orthographic code. The question of how to reconcile these results with other TL manipulations investigating vowel versus consonant transpositions is discussed.

Is the consonant bias specifically human? Long-Evans rats encode vowels better than consonants in words

In natural languages, vowels tend to convey structures (syntax, prosody) while consonants are more important lexically. The consonant bias, which is the tendency to rely more on consonants than on vowels to process words, is well attested in human adults and infants after the first year of life. Is the consonant bias based on evolutionarily ancient mechanisms, potentially present in other species? The current study investigated this issue in a species phylogenetically distant from humans: Long-Evans rats. During training, the animals were presented with four natural word-forms (e.g., mano, "hand"). We then compared their responses to novel words carrying either a consonant (pano) or a vowel change (meno). Results show that the animals were less disrupted by consonantal alterations than by vocalic alterations of words. That is, word recognition was more affected by the alteration of a vowel than a consonant. Together with previous findings in very young human infants, this reliance on vocalic information we observe in rats suggests that the emergence of the consonant bias may require a combination of vocal, cognitive and auditory skills that rodents do not seem to possess.

The mirror reflects more for d than for b: Right asymmetry bias on the visual recognition of words containing reversal letters

Research has shown that recognizing words that contain reversal letters (e.g., b/d) is more difficult than recognizing words that do not contain them. Although none of the current computational models of visual word recognition can account for this effect, it was recently suggested that it may arise from lateral inhibition connections that, at the letter level of processing, can be established between reversal nodes. However, because in writing left-faced letters (e.g., d) are more prone to be reversed into right-faced letters (e.g., b) than the inverse, we hypothesized that the directionality of the reversal letters could modulate the magnitude of the mirror-letter interference effect. In this study, we directly tested this hypothesis by using a highly controlled set of European Portuguese (EP) words containing only either the mirror-letter b or the mirror-letter d in three lexical decision (go/no-go) masked priming experiments conducted with EP adult skilled readers (Experiment 1) and two groups of EP developing readers (third-grade children [Experiment 2] and fifth-grade children [Experiment 3]). Results showed that reliable mirror-letter interference effects were observed only for d-words in both adult skilled readers and fifth-grade children, which asks for additional amendments in the current computational models of visual word recognition.

Consonant and Vowel Processing in Word Form Segmentation: An Infant ERP Study

Segmentation skill and the preferential processing of consonants (C-bias) develop during the second half of the first year of life and it has been proposed that these facilitate language acquisition. We used Event-related brain potentials (ERPs) to investigate the neural bases of early word form segmentation, and of the early processing of onset consonants, medial vowels, and coda consonants, exploring how differences in these early skills might be related to later language outcomes. Our results with French-learning eight-month-old infants primarily support previous studies that found that the word familiarity effect in segmentation is developing from a positive to a negative polarity at this age. Although as a group infants exhibited an anterior-localized negative effect, inspection of individual results revealed that a majority of infants showed a negative-going response (Negative Responders), while a minority showed a positive-going response (Positive Responders). Furthermore, all infants demonstrated sensitivity to onset consonant mispronunciations, while Negative Responders demonstrated a lack of sensitivity to vowel mispronunciations, a developmental pattern similar to previous literature. Responses to coda consonant mispronunciations revealed neither sensitivity nor lack of sensitivity. We found that infants showing a more mature, negative response to newly segmented words compared to control words (evaluating segmentation skill) and mispronunciations (evaluating phonological processing) at test also had greater growth in word production over the second year of life than infants showing a more positive response. These results establish a relationship between early segmentation skills and phonological processing (not modulated by the type of mispronunciation) and later lexical skills.

The Developmental Origins of the Consonant Bias in Lexical Processing

Consonants have been proposed to carry more of the weight of lexical processing than vowels. This consonant bias has consistently been found in adults and has been proposed to facilitate early language acquisition. We explore the origins of this bias over the course of development and in infants learning different languages. Although the consonant bias was originally thought to be present at birth, evidence suggests that it arises from the early stages of phonological and (pre-)lexical acquisition. We discuss two theories that account for the acquisition of the consonant bias: the lexical and acoustic-phonetic hypotheses.

Consonant/vowel asymmetry in early word form recognition

Previous preferential listening studies suggest that 11-month-olds' early word representations are phonologically detailed, such that minor phonetic variations (i.e., mispronunciations) impair recognition. However, these studies focused on infants' sensitivity to mispronunciations (or omissions) of consonants, which have been proposed to be more important for lexical identity than vowels. Even though a lexically related consonant advantage has been consistently found in French from 14 months of age onward, little is known about its developmental onset. The current study asked whether French-learning 11-month-olds exhibit a consonant-vowel asymmetry when recognizing familiar words, which would be reflected in vowel mispronunciations being more tolerated than consonant mispronunciations. In a baseline experiment (Experiment 1), infants preferred listening to familiar words over nonwords, confirming that at 11 months of age infants show a familiarity effect rather than a novelty effect. In Experiment 2, which was constructed using the familiar words of Experiment 1, infants preferred listening to one-feature vowel mispronunciations over one-feature consonant mispronunciations. Given the familiarity preference established in Experiment 1, this pattern of results suggests that recognition of early familiar words is more dependent on their consonants than on their vowels. This adds another piece of evidence that, at least in French, consonants already have a privileged role in lexical processing by 11 months of age, as claimed by Nespor, Peña, and Mehler (2003).