LASTU: A psycholinguistic search tool for Finnish lexical stimuli.

LASTU is a tool for searching for Finnish language stimulus words for psycholinguistic studies. The tool allows the user to query a number of properties, including forms, lemmas, frequencies, and morphological features. It also includes two new measures for quantifying lemma and form ambiguity. The tool is written in Python and is available for Windows and macOS platforms. It is available at https://osf.io/j8v6b/ . Included with the tool is a database based on a massive corpus of dependency-parsed Finnish language data crawled from the Internet (over 5 billion tokens). While LASTU has been developed for researchers working on the Finnish language, the openly available implementation can also be applied to other languages.

Effects of lexical skills and orthographic neighborhood size in word memory.

Two experiments were designed to investigate the relationship between individual lexical skills in young adults and memory performance on words varying by their orthographic neighborhood size. In Experiment 1, a sample of 100 university students were administrated a set of spelling, reading, and vocabulary tests to assess their lexical skills. Then, they had to learn mixed lists of words from high and low neighborhood size and perform free recall and memory recognition tasks. Importantly, high lexical skills were found to enhance free recall and, to a lesser extent, recognition. In addition, a typical mirror effect of neighborhood size was found in recognition as words were better recognized and also produced less false alarms when they had a low neighborhood size. In Experiment 2, pure lists of words were designed and a new sample of 90 university students was assessed. We replicated the effect of lexical skills in free recall and the effect of neighborhood size for hits in recognition. Spelling skills were found to interact with neighborhood size in free recall in that low spelling skills were associated with a facilitatory effect of neighborhood size. In recognition, a relation between reading skills and neighborhood size was found such that the higher the reading skills, the higher was the inhibitory effect of neighborhood size. These results provide new evidence of an influence of lexical skills in word memory performance and underline the role of orthographic neighborhood size in episodic memory tasks.

Reduction or enhancement? Repetition effects on early brain potentials during visual word recognition are frequency dependent.

Most studies on word repetition have demonstrated that repeated stimuli yield reductions in brain activity. Despite the well-known repetition reduction effect, some literature reports repetition enhancements in electroencephalogram (EEG) activities. However, although studies of object and face recognition have consistently demonstrated both repetition reduction and enhancement effects, the results of repetition enhancement effects were not consistent in studies of visual word recognition. Therefore, the present study aimed to further investigate the repetition effect on the P200, an early event-related potential (ERP) component that indexes the coactivation of lexical candidates during visual word recognition. To achieve a high signal-to-noise ratio, EEG signals were decomposed into various modes by using the Hilbert-Huang transform. Results demonstrated a repetition enhancement effect on P200 activity in alpha-band oscillation and that lexicality and orthographic neighborhood size would influence the magnitude of the repetition enhancement effect on P200. These findings suggest that alpha activity during visual word recognition might reflect the coactivation of orthographically similar words in the early stages of lexical processing. Meantime, there were repetition reduction effects on ERP activities in theta-delta band oscillation, which might index that the lateral inhibition between lexical candidates would be omitted in repetition.

The Persian Lexicon Project: minimized orthographic neighbourhood effects in a dense language.

In recent years large datasets of lexical processing times have been released for several languages, including English, French, Spanish, and Dutch. Such datasets have enabled us to study, compare, and model the global effects of many psycholinguistic measures such as word frequency, orthographic neighborhood (ON) size, and word length. We have compiled and publicly released a frequency and ON dictionary of 64,546 words and 1800 plausible NWs from a language that has been relatively little studied by psycholinguists: Persian. We have also collected visual lexical decision reaction times for 1800 Persian words and nonwords. Persian offers an interesting psycholinguistic environment for several reasons, including that it has few long words and has resultantly dense orthographic neighborhoods. These characteristics provide us with an opportunity to contrast how these factors affect lexical access by comparing them to several other languages. The results suggest that sensitivity to word length and orthographic neighbourhood may reflect the statistical structure of a particular language, rather than being a universal element of lexical processing. The dictionary and LDRT data are available from https://osf.io/tb4m6/ .

The Influence of Negative Orthographic Neighborhood in the Lexical Decision Task: Valence and Arousal Contributions.

This study investigated whether the visual recognition of neutral words might be influenced by the emotional dimensions (i.e., valence and arousal) of orthographically similar lexical representations, and whether this might also depend on emotional-related traits of participants (i.e., alexithymia). To this end, 108 participants performed a lexical decision task with 80 neutral words with a higher frequency orthographic neighbor that varied in valence (from neutral to negative) and arousal (from low to high). The main finding was the expected interaction effect between the valence and arousal of the neighbor on the lexical decision times of neutral stimulus words. Longer reaction times were found when the valence score of the neighbor decreased from neutral to negative for words with a low-arousal orthographic neighbor while this emotional neighbor effect was reversed for words with a high-arousal negative neighbor. This combined influence of the valence and arousal of the neighbor was interpreted in terms of increased lexical competition processes and direct influence of the affective system on the participant's response. Moreover, this interaction effect was smaller when the level of alexithymia of the participants increased, suggesting that people with a higher level of alexithymia are less sensitive to the emotional content of the neighbor. The results are discussed within an interactive activation model of visual word recognition incorporating an affective system with valence and arousal dimensions, with regard to the role of the alexithymia level of participants.

WordPars: A tool for orthographic and phonological neighborhood and other psycholinguistic statistics in Persian.

This paper presents a Windows program providing statistics on word and non-word stimuli in Persian, including word frequency, orthographic and phonological length, orthographic and phonological neighbors, and transposed-letter neighbors. It also generates possible non-words that are orthographic neighbors of the target word. Persian is an under-represented Indo-European language that has historically been influenced by Arabic and adopted certain characteristics in its writing, e.g., the omission of short vowels. This tool aims to help researchers in psycholinguistics, specifically with regard to isolated word recognition in Persian. This downloadable program computes the aforementioned indices free of charge. This tool uses two corpora, i.e., Zaya corpus and WorldLex, for reporting and computing statistics and is a user-friendly program provided in English that is also easy to work with for non-Persian researchers. It can be accessed from https://github.com/ssaneei/Wordpars .

The Effects of Orthographic Neighborhood Size and the Influence of Individual Differences in Linguistic Skills During the Recognition of Chinese Words.

There are still inconsistencies as to whether frequency and orthographic neighborhood size affect the reading and recognition of Chinese words. In addition, research on Chinese reading still adheres to the view that "all skilled readers read in the same way" and pays little attention to the influence of individual differences in linguistic skills on word recognition. In this research, we studied the recognition of Chinese two-character words in a lexical decision task (LDT) by manipulating neighborhood size and word frequency and controlling the frequency of the initial constituent character. Individual differences in linguistic skills were assessed through tests of spelling and reading comprehension. The results showed that: (1) A larger orthographic neighborhood size of the initial character had a facilitative effect on Chinese word recognition. The orthographic neighborhood size effect is modulated by word frequency, but this modulation effect was not stable. (2) Spelling and reading comprehension skills are good indicators to assess individual differences in Chinese linguistic skills, and they are significantly correlated. (3) Individual differences in linguistic skills influence the neighborhood size effect, which is moderated by word frequency.

Eye Movement Measures of Within-Language and Cross-Language Activation During Reading in Monolingual and Bilingual Children and Adults: A Focus on Neighborhood Density Effects.

We used eye movement measures of first-language (L1) and second-language (L2) paragraph reading to investigate how the activation of multiple lexical candidates, both within and across languages, influences visual word recognition in four different age and language groups: (1) monolingual children; (2) monolingual young adults; (3) bilingual children; and (4) bilingual young adults. More specifically, we focused on within-language and cross-language orthographic neighborhood density effects, while controlling for the potentially confounding effects of orthographic neighborhood frequency. We found facilitatory within-language orthographic neighborhood density effects (i.e., words were easier to process when they had many vs. few orthographic neighbors, evidenced by shorter fixation durations) across the L1 and L2, with larger effects in children vs. adults (especially the bilingual ones) during L1 reading. Similarly, we found facilitatory cross-language neighborhood density effects across the L1 and L2, with no modulatory influence of age or language group. Taken together, our findings suggest that word recognition benefits from the simultaneous activation of visually similar word forms during naturalistic reading, with some evidence of larger effects in children and particularly those whose words may have differentially lower baseline activation levels and/or weaker links between word-related information due to divided language exposure: bilinguals.

Orthographic neighborhood density modulates the size of transposed-letter priming effects.

We used transposed-letter (TL) priming to test the lexical tuning hypothesis, which states that words from high-density orthographic neighborhoods have more precise orthographic codes than words from low-density neighborhoods. Replicating standard TL priming effects, target words elicited faster lexical decision responses and smaller amplitude N250s and N400s when preceded by TL primes (e.g., leomn-LEMON) compared with substitution primes (e.g., leuzn-LEMON) overall. We expected that if high-density words have more precise orthographic representations (i.e., with each letter assigned to a specific position), then they should be relatively less activated by TL primes and should give rise to smaller TL priming effects. In line with our prediction, N250 (but not N400 or behavioral) TL priming was significantly smaller for high-density words compared with low-density words over posterior sites. Such an interaction was not observed for pseudoword targets. Consistent with the lexical tuning hypothesis then, this pattern suggests that the nature of the orthographic code used to access lexical representations differs depending on the number of neighboring words in the lexicon. We conclude by discussing how lexical tuning could be implemented in current models of orthographic processing.

The complex interactions of context availability, polysemy, word frequency, and orthographic variables during lexical processing.

In this study we examined the interactions of context availability, polysemy, word frequency, and orthographic neighborhood variables during lexical processing. Context availability and polysemy interacted, in that words that were both lower in context availability and had fewer related senses were especially disadvantaged, as was originally reported by Tokowicz and Kroll (2007). Word frequency interacted with both polysemy and context availability, in that the effects of polysemy and context availability were stronger for lower-frequency words. Finally, orthographic neighborhood size and frequency both interacted with polysemy: the effect of polysemy was greater for words with smaller orthographic neighborhoods and a greater number of higher-frequency neighbors. These findings provide support for the context availability hypothesis (Schwanenflugel & Shoben, 1983). Specifically, the feedback activation account (Hino & Lupker, 1996) offers a mechanistic explanation of our findings that is rooted in feedback from semantic to orthographic representations.

Task modulates ERP effects of orthographic neighborhood for pseudowords but not words.

Words and pseudowords from high-density orthographic neighborhoods elicit larger amplitude N400s than similar items from low-density orthographic neighborhoods in the lexical decision task. This pattern could be interpreted as an increase in the amount of lexico-semantic information to be processed or as an increase in difficulty identifying a word (or rejecting a pseudoword) amongst many co-activated alternatives. In order to dissociate between these mechanisms, we compared neighborhood effects between a lexical decision task (LDT) and a letter search task (LST). Behaviorally, we found the standard neighborhood and lexicality effects in the LDT, but no significant effects in the LST. Thus, behavioral responses were sensitive to the decisions required by the respective tasks. Electrophysiologically, we found similar N400 neighborhood effects between tasks for words, but the N400 neighborhood effect for pseudowords was only present in the LDT. Moreover, the effect of neighborhood in the LDT occurred earlier for words than for pseudowords. These nuanced differences in the time course and automaticity of word and pseudoword neighborhood effects lend insight into the processes that underlie N400 effects of orthographic neighborhood and how they unfold over time. We propose that the early neighborhood effects for words across tasks were driven by highly automatized word identification processes that were sensitive to the lateral inhibition generated by orthographic neighbors. In contrast, the later neighborhood effects for pseudowords in the LDT could have been driven by task-specific processes tied to how global lexical activity is used to make a lexical decision.

Disentangling cross-language orthographic neighborhood from markedness effects in L2 visual word recognition.

Previous research has reported that lexical access in bilinguals is language non-selective. In the present study, we explored the extent to which cross-language orthographic neighborhood size (N-size) effects, an index of language non-selectivity, should be dissociated from markedness effects, a sub-lexical orthographic variable referring to the degree of language- shared (unmarked) versus specific (marked) orthography. Two proficiency groups of French/English bilinguals performed an English (L2) lexical decision task with three word and non-word conditions: (1) English words with large French N-size/unmarked orthography (price), (2) small French N-size/unmarked orthography (drive), and (3) small French N-size/marked orthography (write). Evidence was found for orthographic markedness effects, albeit with a different pattern for word and non-word processing: while marked words were facilitated (responded to faster and more accurately) compared to unmarked words, the opposite pattern emerged for non-words. The pattern of results was comparable in both proficiency groups. No evidence emerged for the influence of first language (L1) neighborhood on L2 word or non-word processing. Thus, the results emphasize the need to integrate orthographic markedness as a relevant psycholinguistic variable in bilingual models of visual word recognition such as BIA/+ and to take it into account when investigating cross- language effects and the issue of language non-selectivity during visual word recognition.

Orthographic Networks in the Developing Mental Lexicon. Insights From Graph Theory and Implications for the Study of Language Processing.

In this study, we examine the development of orthographic networks in the mental lexicon using graph theory. According to this view, words are represented by nodes in a network and connected as a function of their orthographic similarity. With a sampling approach based on a language corpus for German school children, we were able to simulate lexical development for children from Grade 1-8. By sampling different lexicon sizes from the corpus, we were able to analyze the content of the orthographic lexicon at different time points and examined network characteristics using graph theory. Results show that, similar to semantic and phonological networks, orthographic networks possess small-word characteristics defined by short average path lengths between nodes and strong local clustering. Moreover, the interconnectivity of the network decreases with growth. Implications for the study of the effect of network measures on language processing are discussed.

Revisiting the Neighborhood: How L2 Proficiency and Neighborhood Manipulation Affect Bilingual Processing.

We conducted three neighborhood experiments with Dutch-English bilinguals to test effects of L2 proficiency and neighborhood characteristics within and between languages. In the past 20 years, the English (L2) proficiency of this population has considerably increased. To consider the impact of this development on neighborhood effects, we conducted a strict replication of the English lexical decision (ELD) task by van Heuven et al. (1998, Experiment 4). In line with our prediction, English characteristics (neighborhood size, word and bigram frequency) dominated the word and non-word responses, while the non-words also revealed an interaction of English and Dutch neighborhood size. The prominence of English was tested again in two experiments introducing a stronger neighborhood manipulation. In ELD and progressive demasking, English items with no orthographic neighbors at all were contrasted with items having neighbors in English or Dutch ('hermits') only, or in both languages. In both tasks, target processing was affected strongly by the presence of English neighbors, but only weakly by Dutch neighbors. Effects are interpreted in terms of two underlying processing mechanisms: language-specific global lexical activation and lexical competition.

Exploring orthographic neighborhood size effects in a computational model of Chinese character naming.

Orthographic neighborhood (N) size effects have been extensively studied in English consistently producing a facilitatory effect in word naming tasks. In contrast, several recent studies on Chinese character naming have demonstrated an inhibitory effect of neighborhood size. Response latencies tend to be inhibited by inconsistent characters with large neighborhoods relative to small neighborhoods. These differences in neighborhood effects between languages may depend on the characteristics (depth) of the mapping between orthography and phonology. To explore this, we first conducted a behavioral experiment to investigate the relationship between neighborhood size, consistency and reading response. The results showed an inhibitory effect of neighborhood size for inconsistent characters but a facilitatory effect for consistent characters. We then developed two computational models based on parallel distributed processing principles to try and capture the nature of the processing that leads to these results in Chinese character naming. Simulations using models based on the triangle model of reading indicated that consistency and neighborhood size interact with the division of labor between semantics and phonology to produce these effects.

The Influence of Orthographic Neighborhood Density and Word Frequency on Visual Word Recognition: Insights from RT Distributional Analyses.

The effects of orthographic neighborhood density and word frequency in visual word recognition were investigated using distributional analyses of response latencies in visual lexical decision. Main effects of density and frequency were observed in mean latencies. Distributional analyses additionally revealed a density × frequency interaction: for low-frequency words, density effects were mediated predominantly by distributional shifting whereas for high-frequency words, density effects were absent except at the slower RTs, implicating distributional skewing. The present findings suggest that density effects in low-frequency words reflect processes involved in early lexical access, while the effects observed in high-frequency words reflect late postlexical checking processes.

Development of neural basis for chinese orthographic neighborhood size effect.

The brain activity of orthographic neighborhood size (N size) effect in Chinese character naming has been studied in adults, meanwhile behavioral studies have revealed a developmental trend of Chinese N-size effect in developing readers. However, it is unclear whether and how the neural mechanism of N-size effect changes in Chinese children along with development. Here we address this issue using functional magnetic resonance imaging. Forty-four students from the 3(rd) , 5(th) , and 7(th) grades were scanned during silent naming of Chinese characters. After scanning, all participants took part in an overt naming test outside the scanner, and results of the naming task showed that the 3(rd) graders named characters from large neighborhoods faster than those from small neighborhoods, revealing a facilitatory N-size effect; the 5(th) graders showed null N-size effect while the 7(th) graders showed an inhibitory N-size effect. Neuroimaging results revealed that only the 3(rd) graders exhibited a significant N-size effect in the left middle occipital activity, with greater activation for large N-size characters. Results of 5(th) and 7(th) graders showed significant N-size effects in the left middle frontal gyrus, in which 5(th) graders induced greater activation in large N-size condition than in small N-size condition, while 7(th) graders exhibited an opposite effect which was similar to the adult pattern reported in a previous study. The current findings suggested the transition from broadly tuned to finely tuned orthographic representation with reading development, and the inhibition from neighbors' phonology for higher graders. Hum Brain Mapp 37:632-647, 2016. © 2015 Wiley Periodicals, Inc.

Density and length in the neighborhood: Explaining cross-linguistic differences in learning to read in English and Dutch.

Two experiments examined underlying cognitive processes that may explain why it is harder to learn to read in English than in more transparent orthographies such as German and Dutch. Participants were English and Dutch readers from Grades 3 and 4. Experiment 1 probed the transition from serial to more parallel processing, as measured by the word length effect for words and pseudowords. English children took longer to make the transition to more parallel reading strategies for words than Dutch children. In contrast, Dutch children continued to use more serial reading strategies for pseudowords. Experiment 2 investigated children's sensitivity to the orthographic overlap between words, as measured by the size of orthographic neighborhood effects for words and pseudowords. Children reading Dutch showed greater sensitivity to the overlap between both words and pseudowords than English children. Cross-linguistic differences in the transition from serial to parallel reading strategies are discussed within the framework offered by the self-teaching hypothesis and the orthographic depth hypothesis. Finally, it is argued that differences between the two languages in the effect of orthographic neighborhood size are a result of cross-linguistic differences in orthographic density and not cross-linguistic differences in orthographic transparency.

Hemispheric differences in orthographic and semantic processing as revealed by event-related potentials.

Differences in how the right and left hemispheres (RH, LH) apprehend visual words were examined using event-related potentials (ERPs) in a repetition paradigm with visual half-field (VF) presentation. In both hemispheres (RH/LVF, LH/RVF), initial presentation of items elicited similar and typical effects of orthographic neighborhood size, with larger N400s for orthographically regular items (words and pseudowords) than for irregular items (acronyms and meaningless illegal strings). However, hemispheric differences emerged on repetition effects. When items were repeated in the LH/RVF, orthographically regular items, relative to irregular items, elicited larger repetition effects on both the N250, a component reflecting processing at the level of visual form (orthography), and on the N400, which has been linked to semantic access. In contrast, in the RH/LVF, repetition effects were biased toward irregular items on the N250 and were similar in size across item types for the N400. The results suggest that processing in the LH is more strongly affected by wordform regularity than in the RH, either due to enhanced processing of familiar orthographic patterns or due to the fact that regular forms can be more readily mapped onto phonology.

Efeitos da similaridade ortográfica das pseudopalavras no acesso lexical / Pseudowords' orthographic similarity effects on lexical access / Efectos de la similitud ortográfica de las pseudopalabras en el acceso lexical

O presente estudo investigou o efeito que a similaridade ortográfica de um estímulo tem no tempo de reação e na precisão dos participantes em uma tarefa de decisão lexical. Para tanto, contou com pseudopalavras que correspondiam a uma manipulação fatorial de duas medidas de similaridade ortográfica: N - o número de vizinhos ortográficos formados pela substituição de uma letra do estímulo-alvo (p. ex.: 'navela' e 'novela') e TLN - o número de vizinhos ortográficos formados pela inversão na ordem de duas letras do estímulo-alvo (p. ex.: 'ânuglo' e 'ângulo'). Participaram da pesquisa 20 estudantes de um curso de pós-graduação em Psicologia, selecionados por amostragem não probabilística de conveniência. Utilizou-se um delineamento de medidas repetidas do tipo 2 x 2, correspondendo a uma manipulação fatorial de N e TLN. Observou-se uma interação entre TLN e N, na qual TLN apresentou um efeito inibidor apenas para as pseudopalavras que não tinham vizinhos ortográficos formados pela substituição de uma letra. Argumentou-se que o efeito de TLN traz desafios para os esquemas representacionais dos modelos atuais de leitura hábil(AU)

The present study investigated the effects that a stimulus’ orthographic similarity has in the participant’s reaction time and precision in a lexical decision task. The pseudowords in the lexical decision task corresponded to a factorial manipulation of two measures of orthographic similarity: N – the number of substitution neighbors (e.g., ‘hink’ and ‘hank’) and TLN – the number of transposed letter neighbors (e.g., ‘anlge’ and ‘angle’). A non-probabilistic sample of twenty graduated psychology students took part in this study. The experimental design consisted of a factorial manipulation of N and TLN in 2 x 2 within-subjects design. An interaction between N and TLN was observed, because TLN only inhibited the processing of pseudowords without substitution neighbors. It was argued that the TLN effect calls into question the representational schemas of nowadays skilled reading models(AU)

El presente estudio investigó el efecto que la similitud ortográfica de un estímulo tiene en el tiempo de reacción y en la precisión de los participantes en una tarea de decisión léxica. Las pseudopalabras en la tarea de decisión léxica corresponden a una manipulación factorial de dos medidas de similitud ortográfica: N – el número de vecinos ortográficos formados mediante la sustitución de una letra del estímulo (p. ej., “navela” y la “novela”) y TLN - el número de vecinos ortográficos formados por la inversión en el orden de dos letras del estímulo (p. ej., “ánuglo” y “ángulo”). Los participantes fueron 20 estudiantes de un curso de post-graduación de psicología, seleccionados a través de muestreo no probabilístico de conveniencia. Se utilizó un diseño de medidas repetidas tipo 2 x 2, correspondiente a una manipulación factorial de N y TLN. Se observó una interacción entre N y TLN, en la cual TLN inhibió el procesamiento solamente para las pseudopalabras sin vecinos de sustitución. Se argumentó que el efecto TLN trae desafíos para los sistemas de representación de los modelos actuales de la lectura hábil(AU)