Is nevtral NEUTRAL? Visual similarity effects in the early phases of written-word recognition

On the distinction between position and order information when processing strings of characters

To probe the processing of gaze-dependent positional information and gaze-independent order information when matching strings of characters, we compared effects of visual similarity (hypothesized to affect gaze-centered position coding) with the effects of character transpositions (hypothesized to affect the processing of gaze-independent order information). In Experiment 1, we obtained empirical measures of visual similarity for pairs of characters, separately for uppercase consonants and keyboard symbols. These similarity values were then used in Experiment 2 to create pairs of four-character stimuli (four letters or four symbols) that could differ by substituting one character with a different character from the same category that was visually similar (e.g., FJDK-FJBK) or dissimilar (e.g., FJVK-FJBK). We also compared the effects of transposing two characters (e.g., FBJK-FJBK) with substituting two characters (e.g., FHSK-FJBK). "Different" responses were harder to make in the single substitution condition when the substituted character was visually similar, and this effect was not conditioned by character type. On the other hand, transposition costs (i.e., greater difficulty in detecting a difference with transpositions compared with double substitutions) were greater for letters compared with symbols. We conclude that visual similarity mainly affects the generic gaze-dependent processing of complex visual features, and that the encoding of letter order involves a mechanism that is specific to reading.

One more trip to Barcetona: on the special status of visual similarity effects in city names

Previous research has shown that, unlike misspelled common words, misspelled brand names are sensitive to visual letter similarity effects (e.g., amazom is often recognized as a legitimate brand name, but not amazot). This pattern poses problems for those models that assume that word identification is exclusively based on abstract codes. Here, we investigated the role of visual letter similarity using another type of word often presented in a more homogenous format than common words: city names. We found a visual letter similarity effect for misspelled city names (e.g., Barcetona was often recognized as a word, but not Barcesona) for relatively short durations of the stimuli (200 ms; Experiment 2), but not when the stimuli were presented until response (Experiment 1). Notably, misspelled common words did not show a visual letter similarity effect for brief 200- and 150-ms durations (e.g., votume was not as often recognized as a word than vosume; Experiments 3-4). These findings provide further evidence that the consistency in the format of presentations may shape the representation of words in the mental lexicon, which may be more salient in scenarios where processing resources are limited (e.g., brief exposure presentations).

Just a mark: Diacritic function does not play a role in the early stages of visual word recognition

A very common feature in most writing systems is the presence of diacritics: distinguishing marks that are added for various linguistic reasons. Most models of reading, however, have not yet captured the nature of these marks. Recent priming experiments in several languages have attempted to resolve how diacritical letters are represented in the visual word recognition system. Since the function and appearance of diacritics can change from one language to the other, it is hard to interpret the accumulated evidence. With this in mind, we conducted two masked priming lexical decision experiments in Hungarian, a transparent orthography with a wide use of diacritic vowels that allows for clear-cut manipulations. In the two experiments, we manipulated the presence or absence of the same diacritic (i.e., the acute accent) on two specific sets of letters that behave differently. In Experiment 1, the manipulation changed only the length of vowels, whereas in Experiment 2, it also changed the quality (e.g., a↝/ɒ/ vs. á↝/aː/). In both experiments, we found that primes with an omitted diacritic work just as good as the identity primes (nema→NÉMA = néma→NÉMA [mute]), whereas the addition of a diacritic comes with a cost (mése→MESE > mese→MESE [tale]). This asymmetry favors a purely perceptual account of the very early stages of word recognition, making it blind to the function of diacritics. We suggest that the linguistic functions of diacritics originate at later processing stages.

Breaking the boundaries: the power of ligatures in visual-word recognition

Introduction

Current neurobiological-inspired models of visual-word recognition propose that letter detectors in the word recognition system can tolerate some variations in the visual form of the letters. However, it is unclear whether this tolerance extends to novel ligatures, which combine two letters into a single glyph.

Methods

To investigate this, the present study utilized a masked priming experiment with a lexical decision task to examine whether primes containing novel ligatures are effective in activating their corresponding base word, relative to omitted-letter primes, in the initial stages of word processing. For each target word (e.g., VIRTUAL), were created an identity prime (virtual), a prime containing a novel ligature of two of the letters (e.g., virtual; "ir" in a single glyph), and an omitted-letter prime where one letter was removed (e.g., vrtual [omitted-vowel] in Experiment 1; vitual [omitted-consonant] in Experiment 2).

Results

Results showed that the presence of a novel ligature in the prime resulted in faster lexical decision times compared to a prime with an omitted vowel (Experiment 1), but not with an omitted consonant (Experiment 2). Furthermore, the performance with the primes containing the novel ligature was not different from that of the identity primes.

Discussion

These results suggest that the word recognition system can quickly enable separate letter detectors for novel ligatures. These findings have important implications for our understanding of the front-end of visual-word recognition.

Do Diacritics Entail an Early Processing Cost in the Absence of Abstract Representations? Evidence from Masked Priming in English

Using the masked priming technique, word recognition experiments in various languages have shown slower response times for a target word like NEVEU (nephew, in French) when preceded by a diacritical prime like néveu than by the identity prime neveu. The most common account of this effect is linguistic: diacritical and non-diacritical vowels (e.g., é and e) activate different letter representations (e.g., compare neveu /nə.vø/ vs. néveu /ne.vø/). However, another explanation is that the reduced effectiveness of the diacritical primes is merely due to the perceptual salience of accent marks in the first moments of word processing. Here, we designed a masked priming experiment that tested this perceptual salience account by comparing the effectiveness of diacritical versus non-diacritical primes in a language where diacritics have no linguistic value, namely, English (e.g., nórth-NORTH vs. north-NORTH). We found a small but reliable cost due to the diacritical primes, thus revealing that perceptual salience reduced the effectiveness of the primes. However, the effect sizes were substantially smaller than in the experiments in languages with diacritical marks, thus suggesting that the néveu-NEVEU versus neveu-NEVEU difference relies on both linguistic and perceptual sources.

Factors Influencing the Accurate Identification of Written Minimal Pairs with Graphemic Similarity: Evidence from Persian-Speaking Children and Adults

In this study, we compared children's and adults' ability to accurately identify target words in written minimal pairs (WMPs) with graphemically similar letters while accounting for factors such as gender, similarity of the middle letter in WMPs, mono- versus dimorphemic WMPs, number of syllable, homography, and imageability. Fifty children and fifty adults were exposed to a distractor stimulus as a pre-mask, followed by the target, and then a post-mask stimulus. Subsequently, the corresponding WMPs including the target word and its graphemically minimal contrast were presented to the participants to obtain their reaction time (RT) in accurately identifying the target word. Results demonstrated that children tend to slow down their reaction as a compensatory strategy to circumvent their less mature knowledge of graphophonic units/morphemes to achieve accuracy during word recognition. In addition, among all controlled factors, children's RT was significantly influenced by similarity of the middle letter in the WMPs. Adults' RT, however, was influenced by factors such as gender, similarity of the middle letter in WMPs, and homography.

The sequence effect: Character position processing in Chinese words

Numerous studies indicate that letter position processing is important for word recognition; also, the position processing of external letters (especially the initial letter) is better than that of inner letters in the Roman script. Similarly, the position processing of characters is critical in Chinese word recognition. However, the position processing pattern of characters within Chinese words is still understudied. Therefore, using a single-presentation lexical decision task with 79 university students in China, we conducted two experiments with three- and four-character words to explore this issue. The results revealed clear character position processing with transposed pseudowords. Crucially, we identified a sequence effect in Chinese character position processing within words, directly supporting the hypothesis that character-based processing occurs with Chinese words. We also discussed other possibilities in Chinese character position processing.

EXPRESS: Orthographic and feature-level contributions to letter identification

Word recognition is facilitated by primes containing visually similar letters (dentjst-dentist, Marcet & Perea, 2017), suggesting that letter identities are encoded with initial uncertainty. Orthographic knowledge also guides letter identification, as readers are more accurate at identifying letters in words compared to pseudowords (Reicher, 1969; Wheeler, 1970). We investigated how higher-level orthographic knowledge and low-level visual feature analysis operate in combination during letter identification. We conducted a Reicher-Wheeler task to compare readers' ability to discriminate between visually similar and dissimilar letters across different orthographic contexts (words, pseudowords, and consonant strings). Orthographic context and visual similarity had independent effects on letter identification, and there was no interaction between these factors. The magnitude of these effects indicated that higher-level orthographic information plays a greater role than lower-level visual feature information in letter identification. We propose that readers use orthographic knowledge to refine potential letter candidates while visual feature information is accumulated. This combination of higher-level knowledge and low-level feature analysis may be essential in permitting the flexibility required to identify visual variations of the same letter (e.g. N-n) whilst maintaining enough precision to tell visually similar letters apart (e.g. n-h). These results provide new insights on the integration of visual and linguistic information and highlight the need for greater integration between models of reading and visual processing. This study was pre-registered on the Open Science Framework. Pre-registration, stimuli, instructions, trial-level data, and analysis scripts are openly available (https://osf.io/p4q9u/).

Searching beyond the looking glass with sandwich priming

Duñabeitia et al. (NeuroImage 54(4), 3004-3009, 2011) demonstrated that mirror letters induce the same electrophysiological response as canonical letters during the orthographic stage of visual word recognition. However, behavioral evidence in support of such an effect has remained scarce. We hypothesize that the poor reliability of the behavioral data could be due to the lack of sensitivity of the paradigms used in the literature. In Experiment 1 and Experiment 2, we compared conventional and sandwich-masked priming paradigms. Results showed that mirror primes (mirror) produced a significant priming effect on high-frequency words in the case of sandwich priming only. In Experiment 3, we used sandwich priming with a new material set to address a number of concerns regarding prime-target visual overlap. We obtained a graded facilitatory mirror-letter priming effect that acted additively with lexical frequency, thus supporting the idea that it originates in the fast automatic orthographic stage. Given that the graded priming effect provides little support for the idea of the complete preservation of mirror invariance for non-reversal letters, complementary explanations are explored.

Are brand names special words? Letter visual-similarity affects the identification of brand names, but not common words

Brand names are often considered a special type of words of special relevance to examine the role of visual codes during reading: unlike common words, brand names are typically presented with the same letter‐case configuration (e.g., IKEA, adidas). Recently, Pathak et al. (European Journal of Marketing, 2019, 53, 2109) found an effect of visual similarity for misspelled brand names when the participants had to decide whether the brand name was spelled correctly or not (e.g., tacebook [baseword: facebook] was responded more slowly and less accurately than xacebook). This finding is at odds with both orthographically based visual‐word recognition models and prior experiments using misspelled common words (e.g., viotin [baseword: violin] is identified as fast as viocin). To solve this puzzle, we designed two experiments in which the participants had to decide whether the presented item was written correctly. In Experiment 1, following a procedure similar to Pathak et al. (European Journal of Marketing, 2019, 53, 2109), we examined the effect of visual similarity on misspelled brand names with/without graphical information (e.g., anazon vs. atazon [baseword: amazon]). Experiment 2 was parallel to Experiment 1, but we focused on misspelled common words (e.g., anarillo vs. atarillo; baseword: amarillo [yellow in Spanish]). Results showed a sizeable effect of visual similarity on misspelled brand names – regardless of their graphical information, but not on misspelled common words. These findings suggest that visual codes play a greater role when identifying brand names than common words. We examined how models of visual‐word recognition can account for this dissociation.

What masked priming effects with abbreviations can tell us about abstract letter identities

Models of visual word recognition share the assumption that lexical access is based on abstract letter identities. The present study re-examined the assumption that this is because information about the visual form of the letter is lost early in the course of activating the abstract letter identities. The main support for this assumption has come from the case-independent masked priming effects. Experiment 1 used common English words presented in lowercase as targets in lexical decision, and replicated the oft-reported case-independent identity priming effect (e.g., edge-edge = EDGE-edge). In contrast, Experiment 2 using abbreviations (e.g., DNA, CIA) produced a robust case-dependent identity priming effect (e.g., DNA-DNA < dna-DNA). Experiment 3 used the same abbreviation stimuli as primes in a semantic priming lexical decision experiment. Here the prime case effect was absent, but so was the semantic priming effect (e.g., dna-GENETICS = DNA-GENETICS = LSD-GENETICS). The results question the view that information about the visual form of the letter is lost early. We offer an alternative perspective that the abstract nature of priming for common words stems from how these words are represented in the reader's lexicon. The implication of these findings for letter and word recognition is discussed. (197 words).

Letter identity and visual similarity in the processing of diacritic letters

Are letters with a diacritic (e.g., â) recognized as a variant of the base letter (e.g., a), or as a separate letter identity? Two recent masked priming studies, one in French and one in Spanish, investigated this question, concluding that this depends on the language-specific linguistic function served by the diacritic. Experiment 1 tested this linguistic function hypothesis using Japanese kana, in which diacritics signal consonant voicing, and like French and unlike Spanish, provide lexical contrast. Contrary to the hypothesis, Japanese kana yielded the pattern of diacritic priming like Spanish. Specifically, for a target kana with a diacritic (e.g., ガ, /ga/), the kana prime without the diacritic (e.g., カ, /ka/) facilitated recognition almost as much as the identity prime (e.g., ガ-ガ = カ-ガ), whereas for a target kana without a diacritic, the kana prime with the diacritic produced less facilitation than the identity prime (e.g., カ-カ < ガ-カ). We suggest that the pattern of diacritic priming has little to do with linguistic function, and instead it stems from a general property of visual object recognition. Experiment 2 tested this hypothesis using visually similar letters of the Latin alphabet that differ in the presence/absence of a visual feature (e.g., O and Q). The same asymmetry in priming was observed. These findings are consistent with the noisy channel model of letter/word recognition (Norris & Kinoshita, Psychological Review, 119, 517-545, 2012a).

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.

Does a mark make a difference? Visual similarity effects with accented vowels

Visual similarity effects are pervasive in masked priming (e.g., T4BLE→TABLE; obiect→OBJECT; docurnent→DOCUMENT) and can be easily explained in terms of uncertainty regarding letter identity. However, recent research failed to show visual similarity effects for primes containing accented vowels (e.g., féliz-FELIZ behaves as fáliz-FELIZ [happy in Spanish]). This null effect has been taken to suggest that accented and non-accented vowels (e.g., é and e) activate completely distinct representations. However, priming effects are reinstated for non-accented vowels (e.g., facil-FÁCIL < fecil-FÁCIL [easy in Spanish]). Here we tested the hypothesis that the lack of priming effects for primes containing accented vowels is a simple consequence of the saliency of the accent marks. To investigate this issue, we conducted a masked priming lexical decision experiment in which we minimized the saliency of the diacritical marks by using primes containing the letter i (i.e., a letter that contains itself a glyph over the letter). We manipulated prime-target visual similarity and the presence/absence of an accented vowel in the prime (e.g., obieto-OBJETO vs. obaeto-OBJETO; obíeto-OBJETO vs. obáeto-OBJETO [object in Spanish]). Results showed a sizeable visual similarity effect regardless of whether the prime was accented or not. Therefore, these findings suggest that, at least in scripts like Spanish, there is nothing special about the processing of accented vs. unaccented vowels once the saliency of the diacritical marks is reduced.

A compositional neural code in high-level visual cortex can explain jumbled word reading

We read jubmled wrods effortlessly, but the neural correlates of this remarkable ability remain poorly understood. We hypothesized that viewing a jumbled word activates a visual representation that is compared to known words. To test this hypothesis, we devised a purely visual model in which neurons tuned to letter shape respond to longer strings in a compositional manner by linearly summing letter responses. We found that dissimilarities between letter strings in this model can explain human performance on visual search, and responses to jumbled words in word reading tasks. Brain imaging revealed that viewing a string activates this letter-based code in the lateral occipital (LO) region and that subsequent comparisons to stored words are consistent with activations of the visual word form area (VWFA). Thus, a compositional neural code potentially contributes to efficient reading.

Visual letter similarity effects during sentence reading: Evidence from the boundary technique

The study of how the cognitive system encodes letter identities from the visual input has received much attention in models of visual word recognition but it has typically been overlooked in models of eye movement control in reading. Here we examined how visual letter similarity affects early word processing during reading using Rayner's (1975) boundary change technique in which the parafoveal preview of the target word was either identical (e.g., frito-frito [fried]) or a one-letter-different nonword (e.g., frjto-frito vs. frgto-frito). Critically, the substituted letter in the nonword was visually similar (based on letter confusability norms) or visually dissimilar. Results showed shorter viewing times on the target word when the parafoveal preview was visually similar than when it was visually dissimilar. Thus, visual letter similarity modulates the integration of parafoveal and foveal information during sentence reading. Future implementations of models of eye movement control in reading should incorporate a more developed orthographic-lexical module to capture these effects.

Is there a cost at encoding words with joined letters during visual word recognition?

For simplicity, models of visual-word recognition have focused on printed words composed of separated letters, thus overlooking the processing of cursive words. Manso de Zuniga, Humphreys, and Evett (1991) claimed that there is an early “cursive normalization” encoding stage when processing written words with joined letters. To test this claim, we conducted a lexical decision experiment in which words were presented either with separated or joined letters. To examine if the cost of letter segmentation occurs early in processing, we also manipulated a factor (i.e., word-frequency) that is posited to affect subsequent lexical processing. Results showed faster response times for the words composed of separated letters than for the words composed of joined letters. This effect occurred similarly for low- and high-frequency words. Thus, the present data offer some empirical support to Manso de Zuniga et al.’s (1991) idea of an early “cursive normalization” stage when processing joined-letters words. This pattern of data can be used to constrain the mapping of the visual input into letter and word units in future versions of models of visual word recognition.

Does visual letter similarity modulate masked form priming in young readers of Arabic?

We carried out a masked priming lexical decision experiment to study whether visual letter similarity plays a role during the initial phases of word processing in young readers of Arabic (fifth graders). Arabic is ideally suited to test these effects because most Arabic letters share their basic shape with at least one other letter and differ only in the number/position of diacritical points (e.g., ض - ص ;ظ - ط ;غ - ع ;ث - ت - ن ب ;ذ - د ;خ - ح - ج ;ق - ف ;ش - س ;ز - ر). We created two one-letter-different priming conditions for each target word, in which a letter from the consonantal root was substituted by another letter that did or did not keep the same shape (e.g., خدمة - حدمة vs. خدمة - فدمة). Another goal of the current experiment was to test the presence of masked orthographic priming effects, which are thought to be unreliable in Semitic languages. To that end, we included an unrelated priming condition. We found a sizable masked orthographic priming effect relative to the unrelated condition regardless of visual letter similarity, thereby revealing that young readers are able to quickly process the diacritical points of Arabic letters. Furthermore, the presence of masked orthographic priming effects in Arabic suggests that the word identification stream in Indo-European and Semitic languages is more similar than previously thought.