It has long been held that processing at the single word level during reading is automatic. However, research has recently begun to emerge that challenges this view. The literature surrounding the processing of emotion while recognizing printed words is limited, but some findings in the processing of emotion in faces suggest that negative stimuli (especially threat stimuli) promote quick and accurate processing. The purpose of the present experiments is to investigate whether negative emotionally-laden words are afforded priority processing in visual word recognition compared to positive emotionally-laden words. Two experiments are reported that manipulated the lexicality and valence of the target and distractor stimuli (Experiments 1 & 2), the validity of a spatial pre-cue (Experiments 1 & 2), and the presence of a distractor item (Experiment 2). Participants were asked to determine whether the target stimulus spelled a word or not. Response times on valid trials were faster compared to invalid trials, response times to negative emotionally-laden words were slower compared to positive emotionally-laden words, and the presence of a distractor item encouraged better focus on the target stimuli in the absence of any evidence that the valence of the distractor itself was processed. These results are consistent with the hypothesis that visual word recognition is not automatic given that processing benefited from the accurate direction of spatial attention. Furthermore, negative emotionally-laden words benefited equally compared to positive emotionally-laden words and therefore provide no evidence of automatic processing.

A central issue in word recognition is how readers retrieve and select the right representation among others in the mental lexicon. Recently, it has been claimed that recognition of individual words is influenced by the degree to which the words possess unique vs. shared letters or sounds relative to other words, that is, whether the words have few or several neighbors. Research on so-called neighborhood density effects advances understanding of the organization and operation of the mental lexicon. Orthographic neighborhood effects have been claimed to be facilitative, but recent studies of visual word recognition have led to a revised understanding of the nature of the orthographic neighborhood density effect. Through a reexamination of orthographic and phonological neighborhood density effects, the specific objective of the present research is to understand how orthographic and phonological representations interact across two different writing systems, i.e., English (an alphabetic orthography) and Chinese (a morphosyllabic orthography). The phenomena were studied using a joint behavioral (lexical decision) and neural imaging approach (near infrared spectroscopy, or NIRS). Orthographic and phonological (more, specifically, homophone) neighborhood density were manipulated in three lexical decision experiments with English and three with Chinese readers. After different sources of facilitative inter-lexicon connections were controlled, orthographic and phonological neighborhood density effects were found to be inhibitory in both writing systems. Inhibitory neighborhood density effects were also confirmed in two NIRS experiments of English and Chinese. The present research provided a better control of lexical characteristics than was the case in previous research on neighborhood effects and found a clear and consistent pattern of neighborhood density effects. This research supports interactive-activation models of word recognition rather than parallel-distributed models, given the evidence for lateral inhibition indexed by inhibitory neighborhood density effects. As such, the present study furthers the understanding of the organization and operation of the mental lexicon.

The present study sought to investigate the extent to which masked semantic priming is an automatic process and whether its effects vary depending upon the type of stimuli used. Recent studies have shown that there is a differential priming effect for prime-target pairs with different types of semantic relationships. Here, using a semantic categorization task with masked priming, we compared the effects of synonym, antonym,and associatively related non-exemplar prime-target pairs when presented at different stimulus onset asynchronies (SOAs). Participants took a prime visibility posttest in conjunction with the categorization task which served as a measure of "partial awareness" of the prime. The results here indicate that differences in perceptual awareness may produce differential semantic priming patterns across the semantic relationships and SOAs considered. Potential mechanisms for this divergence are proposed.

It has long been held that processing at the single word level during reading is automatic. However, research has recently begun to emerge that challenges this view. The literature surrounding the processing of emotion while recognizing printed words is limited, but some findings in the processing of emotion in faces suggest that negative stimuli (especially threat stimuli) promote quick and accurate processing. The purpose of the present experiments is to investigate whether negative emotionally-laden words are afforded priority processing in visual word recognition compared to positive emotionally-laden words. Two experiments are reported that manipulated the lexicality and valence of the target and distractor stimuli (Experiments 1 & 2), the validity of a spatial pre-cue (Experiments 1 & 2), and the presence of a distractor item (Experiment 2). Participants were asked to determine whether the target stimulus spelled a word or not. Response times on valid trials were faster compared to invalid trials, response times to negative emotionally-laden words were slower compared to positive emotionally-laden words, and the presence of a distractor item encouraged better focus on the target stimuli in the absence of any evidence that the valence of the distractor itself was processed. These results are consistent with the hypothesis that visual word recognition is not automatic given that processing benefited from the accurate direction of spatial attention. Furthermore, negative emotionally-laden words benefited equally compared to positive emotionally-laden words and therefore provide no evidence of automatic processing.

Number is a grammatical category found in nearly every language around the world (Corbett, 2000). The syntactic expression of number is referred to as grammatical number. In English and French, two number categories are in use: singular and plural. Nouns that are written more frequently in their singular form are called singular-dominant, while those that are written more frequently in their plural form are called plural-dominant. Several lexical decision and picture naming studies have found that grammatical number and noun dominance interact, resulting in a surface frequency effect for singular-dominant nouns only. Singular-dominant nouns are recognized/named significantly faster in their singular form than in their plural form, while plural-dominant nouns are recognized/named equally fast in both forms (e.g., Baayen, Burani, & Schreuder, 1997; Biedermann, Beyersmann, Mason, & Nickels, 2013; Domínguez, Cuetos, & Segui, 1999; New, Brysbaert, Segui, Ferrand, & Rastle, 2004; Reifegerste, Meyer, & Zwitserlood, 2017). The objective of this thesis is to extend our understanding of the singular-dominant noun surface frequency effect in English and French by adopting three procedures. First, advanced linear mixed modelling techniques were used to improve statistical power and accuracy. Second, the noun dominance ratio technique (Reifegerste et al., 2017) was applied to investigate whether the surface frequency effect remains significant when noun dominance was treated as a continuous variable. Third, a determiner-noun number agreement task was created to determine whether the surface frequency effect could be reproduced in a novel task. Three studies were conducted. In Study 1, two lexical decision tasks (LDTs) were conducted. Results revealed that in both English and French, singular nouns were recognized faster than plural nouns while the noun dominance effect was non-significant. The interaction between grammatical number and noun dominance was significant in French and marginally so in English. The interaction pattern was identical in both languages, singular-dominant nouns demonstrated a surface frequency effect while plural nouns did not. In Study 2, three determiner-noun number agreement tasks (NATs) were conducted. Results revealed that in both English and French, plural nouns were recognized faster than singular nouns. No other effects were significant. Incorporating irregular singular nouns (e.g., bonus) and plural nouns (e.g., mice) as foils produced the same results. In Study 3, two LDTs and one NAT were conducted. Lexical decision results revealed that in both English and French, singular nouns were recognized faster than plural nouns. However, the effects of noun collectivity and animacy were significant in English only; non-collective nouns were recognized faster than collective nouns while inanimate nouns were recognized faster than animate nouns. Number agreement results revealed that in English, plural nouns were recognized faster than singular nouns; no other effects reached significance. Taken together, my studies confirm that a strong surface frequency effect exists during visual word recognition for singular-dominant nouns. However, the surface frequency effect does not extend to the formation determiner-noun number agreement decisions, which were influenced nearly exclusively by grammatical number.

Les patients souffrant de schizophrénie présentent des symptômes cliniques ainsi que des déficits cognitifs. Il a été récemment proposé que les déficits de lecture des patients fassent partie de ces déficits. L’objectif de ce travail de thèse était d’évaluer les capacités de reconnaissance visuelle des mots chez les patients souffrant de schizophrénie, au moyen d'une évaluation diagnostique des processus cognitifs dans une approche comportementale et électrophysiologique (enregistrement des potentiels évoqués). Les résultats indiquent une préservation de la spécialisation de l’aire de la forme visuelle des mots pour traiter les mots écrits chez les patients. De plus, les processus cognitifs impliqués dans le traitement orthographique des suites de lettres semblent également préservés. En revanche, les processus cognitifs impliqués dans le traitement phonologique semblent altérés chez les patients souffrant de schizophrénie. / Patients suffering from schizophrenia display clinical symptoms as well as cognitive deficits. Recently, it has been suggested that these patients display, among other things, reading deficits. This doctoral thesis aims to evaluate the abilities of visual word recognition in patients suffering from schizophrenia, using both behavioral and electrophysiological (recording of event related potentials) approaches. The results indicated that the specialization of the visual word form area for processing of written words is preserved for patients. In addition, cognitive processes involved in orthographic processing of letter strings were preserved. By contrast, cognitive processes involved in phonological processing were altered for patients suffering from schizophrenia.

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第20664号 / 医博第4274号 / 新制||医||1024(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 髙橋 良輔, 教授 伊佐 正, 教授 井上 治久 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

L'objectif de cette thèse était d‟étudier les processus d'activation et d'inhibition lexicales sous-tendant la lecture de mots et de déterminer le rôle du système affectif sur ces processus chez l'adulte. Pour cela, nous avons testé les effets de fréquence du voisinage orthographique et de l'émotionalité de ce voisinage dans plusieurs tâches cognitives. Les résultats ont montré un effet de fréquence du voisinage orthographique qui était inhibiteur dans des tâches de reconnaissance visuelle de mots (Expériences 1-4) et facilitateur dans des tâches de catégorisation de couleur de mots (Expériences 6-8). L'inhibition lexicale ralentirait la reconnaissance du mot stimulus et diminuerait ainsi son effet d'interférence dans des tâches de type Stroop. De plus, la valence et le niveau d'arousal du voisin plus fréquent modifiaient également la vitesse de reconnaissance du mot stimulus (Etude préliminaire, Expérience 1-5) et la catégorisation de sa couleur (Expériences 6, 7 et 9). Le système affectif s'activerait lors de la lecture de mots avec un voisin émotionnel et modifierait la propagation d'activation et d'inhibition lexico-émotionnelles. De plus, les résultats indiquaient que ces effets de voisinage orthographique étaient sensibles aux caractéristiques des participants. Une diminution de l'effet de fréquence du voisinage selon l'âge a été montrée et interprétée en termes de déficits conjoints d'activation et d'inhibition lexicales (Expériences 4, 5, 8 et 9). Enfin, l'effet du voisinage émotionnel obtenu suggérait une préservation des processus lexico-émotionnels avec l'avancée en âge (Expériences 4, 5 et 9), mais cet effet était corrélé négativement avec le niveau d'alexithymie des individus (Expériences 2, 4 et 6). Dans l'ensemble, ces données soulignent l‟importance de la prise en compte du système affectif dans les modèles de reconnaissance visuelle des mots. / The aim of this thesis was to study lexical activation and inhibition processes underlying word reading and to determine the role of affective system on these processes in adults. For this, we investigated the effects of orthographic neighbourhood frequency and emotionality of this neighbourhood in several cognitive tasks. Results showed an orthographic neighbourhood frequency effect that was inhibitory in visual word recognition tasks (Experiments 1-4) and facilitatory in colour categorization tasks (Experiments 6-8). Lexical inhibition likely slows down the recognition of the stimulus word as well as diminishing its interference effect in Stroop-like tasks. Moreover, emotional valence and arousal level of the higher-frequency neighbour also modified the speed of stimulus word recognition (Preliminary study, Experiments 1-5) and its colour categorization (Experiments 6, 7 and 9). Thus, the affective system would be activated during reading of words with an emotional neighbour and would modify the spread of lexico-emotional activation and inhibition. Moreover, results indicated that these orthographic neighbourhood effects were sensitive to participants‟ characteristics. A decreaseof the orthographic neighbourhood effect depending on age was shown and interpreted in terms of deficits in both activation and inhibition processes (Experiments 4, 5, 8 and 9). Finally, the emotional neighbourhood effect that was obtained suggested a preservation of lexico-emotional processes with advance in age (Experiments 4, 5, and 9), but this effect was negatively correlated with individuals' level of alexithymia (Experiments 2, 4, and 6). Taken together, thes data underline the importance of taking the affective system into account in models of visual word recognition.

L’objectif de cette thèse était d’étudier les variations possibles des processus impliqués dans la reconnaissance visuelle des mots selon les différences d’habiletés lexicales de lecteurs adultes (niveaux de lecture, orthographe et vocabulaire). Ainsi, nous avons testé l’effet de fréquence du voisinage orthographique par suppression et par substitution d’une lettre dans des tâches de décision lexicale (Exp. 1, 4), démasquage progressif (Exp. 2, 5), dénomination (Exp. 3, 6), et catégorisation de couleur (Exp. 7). Un effet inhibiteur de fréquence du voisinage orthographique par suppression (Exp. 1-3) et par substitution (Exp. 6) d’une lettre a été obtenu. Les temps de réponse étaient plus longs et les taux d’erreurs plus élevés pour les mots avec au moins un voisin orthographique plus fréquent que pour ceux sans un tel voisin, ce qui peut être expliqué en termes de compétition lexicale. De plus, la compétition lexicale du voisin par suppression d’une lettre était plus importante pour les individus ayant des habiletés lexicales hautes plutôt que basses (Exp. 1, 3), ces derniers individus témoignant de difficultés d’inhibition du compétiteur. Par ailleurs, les individus ayant des habiletés lexicales basses étaient moins rapides et moins précis que ceux ayant des habiletés lexicales hautes (Exp. 1-7). Les données de la tâche de catégorisation (Exp. 7) suggèrent des difficultés dans la mise en place de l’inhibition pour ces individus. Enfin, nous avons montré que l’effet de fréquence du voisinage orthographique était influencé par la confusabilité de la lettre substituée, ce qui différait selon les habiletés lexicales des individus (Exp. 4-6). Dans le cadre théorique de l’activation interactive et de codage spatial des lettres, les données soulignent l’importance des différences d’habiletés lexicales des lecteurs pour rendre compte des différences dans la diffusion de l’activation et de l’inhibition lexicales dans la reconnaissance visuelle des mots. / Word recognition, according to the adult readers’ lexical skill differences (reading, spelling and vocabulary levels). To do so, we tested the orthographic neighborhood frequency effect by deletion and substitution of a letter in lexical decision (Exp.1, 4), progressive demasking (Exp 2, 5), denomination (Exp. 3, 6), and color categorization tasks (Exp.7). Response times were longer and the error rates were higher for words with at least one higher frequency neighbor than for words without such a neighbor, which can be explained in terms of lexical competition. In addition, the lexical competition of the higher-frequency deletion neighbor seems more important for individuals with high lexical skills than for those with low lexical skills (Exp 1, 3), the latter showing difficulties in inhibiting the competitor. Furthermore, individuals with low lexical skills were slower and less accurate than those with high lexical skills (Exp 1-7). Data from the categorization task (Exp. 7) suggest difficulties in setting up inhibition for these individuals. Finally, we have shown that the orthographic neighborhood frequency effect was influenced by the confusability of the substituted letter, differing according to the lexical skills of the individuals (Exp 4-6). In the theoretical framework of activation-interactive and spatial coding, the data highlight the importance of readers’ differences in lexical skills for the diffusion of lexical activation and inhibition in visual word recognition.

L’objectif du présent travail est d’une part d’évaluer les performances d’accès au mot chez des adultes jeunes (M = 22.1 ans) et âgés (M = 68.7 ans) et, d’autre part, de préciser la fonctionnalité des processus d’activation et d’inhibition lexicales avec l’âge. Dans le domaine du traitement des mots écrits, six études sont conduites en contrôlant le niveau de vocabulaire des participants. En utilisant des indices lexicaux objectifs et subjectifs adaptés aux adultes jeunes et âgés (Expérience 1a), nous observons une diminution des effets de fréquence objective (Expériences 1b-2) et de fréquence du voisinage orthographique avec l’âge (Expérience 4) dans la tâche de décision lexicale. D’autres données, obtenues avec cette tâche, précisent que la modification de l’effet de fréquence du voisinage avec l’âge est sensible à la familiarité des mots (Expériences 5-6), recueillie auprès d’adultes jeunes et âgés (Expérience 3). Dans le domaine de la production langagière orale, deux études utilisant un paradigme d’induction de Mot sur le Bout de la Langue (MBL) sont menées. Les résultats montrent que le nombre de MBL augmente avec l’âge (Expérience 7), indépendamment du niveau de vocabulaire. De plus, traiter un mot lié en son à la cible facilite autant sa récupération chez les adultes jeunes et âgés, tandis que traiter un mot lié en sens à la cible gêne sa récupération, et ce d’autant plus que les adultes sont âgés (Expérience 8). Dans l’ensemble, l’hypothèse combinée d’un déficit d’activation et d’inhibition, mise en lien avec les caractéristiques langagières des populations, permet de rendre compte de la modification des performances lexicales avec l’âge. / The aim of this study is to evaluate word access performances of young (M = 22.1 years) and older (M = 68.7 years) adults, and to specify possible changes in lexical activation and inhibition processes with aging. In the field of written word processing, six studies were conducted in which the participant vocabulary level was controlled. When using objective and subjective lexical measures appropriated to young and older adults (Experiment 1a), an age-related decreased was found for the objective frequency effect (Experiments 1b-2) and for the orthographic neighborhood frequency effect (Experiment 4) in the lexical decision task. Other data from this task indicated that the age-related change in the neighborhood frequency effect was sensitive to word familiarity ratings (Experiments 5-6) collected from young and older adults (Experiment 3). In field of the oral language production, two studies were run with a paradigm for inducing tip of the tongue (TOT) states. The results indicated that the number of TOT increased with aging (Experiment 7), which was not due to the vocabulary level. In addition, processing a word phonologically related to the target facilitated its recovery in young and older adults while processing a word semantically related to the target hindered its recovery, more for the older that for the young adults (Experiment 8). Overall, the combined hypothesis of activation and inhibition deficits, associated with linguistic characteristics of populations, can account for lexical performance changes with aging.