Estructura morfológica y recuperación léxica

Resumen

El objetivo principal de esta investigación es el de contribuir a un mayor conocimiento del papel que desempeña la estructura morfológica de las palabras en la organización del léxico interno y, por consiguiente, en las estrategias que emplean los sujetos para acceder a la representación mental de las palabras. Más en concreto, se trata de ver cuál es la relación existente entre la representación de la forma base de una palabra (por ej., flor) y la de formas derivadas de la misma (por ej., florero, florecer, florido) de cara a una posible simplificación del inventario mental de entradas léxicas.

Se han realizado tres experimentos, basados en una tarea de decisión léxica y en la utilización de la técnica de «priming» o presentación previa de un supuesto elemento facilitador del reconocimiento de cada estímulo. Se midió la latencia de respuesta para clasificar los estímulos como palabras o no-palabras del idioma. Los dos primeros experimentos se efectuaron bajo la modalidad visual de reconocimiento y el tercero, bajo la modalidad auditiva. En todos los casos, las comparaciones relevantes se establecen entre los TRs correspondientes a una misma palabra en condiciones experimentales diferentes: según vaya precedida por sí misma, o por una relacionada morfológicamente, o cuando no vaya precedida ni por sí misma ni por otra relacionada (condición de control).

Los resultados obtenidos bajo las dos modalidades perceptivas son coincidentes y ponen de manifiesto que: 1) se da un efecto de facilitación en el reconocimiento, tanto al presentar una palabra precedida por sí misma (repetición) como al presentarla precedida por otra relacionada morfológicamente; 2) el efecto de facilitación por repetición es significativamente superior al de facilitación por relación morfológica; y 3) dentro de este último no aparecen diferencias significativas entre la facilitación de la forma base por la derivada y la de ésta por aquélla.

Estos resultados se interpretan a la luz de los distintos modelos propuestos acerca de la representación léxica. Sin que sean cruciales para decidirse por uno de ellos en contra de los otros, sí que parecen apoyar la existencia de un código de representación abstracto que aglutina familias de palabras relacionadas morfológicamente en torno a una misma entrada léxica. En cualquier caso, y aun suponiendo que hubiera entradas léxicas distintas para cada forma particular, sería preciso postular algún mecanismo adicional que diera cuenta del papel que desempeña la información morfológica en la organización general del léxico interno.     

The effect of bilingualism on lexical learning and memory across two language modalities: some evidence for a domain-specific,but not general,advantage

ABSTRACT

The present study was conducted to replicate bilingual advantages in short-term memory for language-like material and word learning in young adults and extend this research to the sign domain, ultimately with the goal of investigating the domain specificity of bilingual advantages in cognition. Data from 112 monolingual hearing non-signers and 78 bilingual hearing non-signers were analysed for this study. Participants completed a battery of tasks assessing sign and word learning, short-term memory, working memory capacity, intelligence, and a language and demographic questionnaire. Overall, the results of this study suggested a bilingual advantage in memory for speech-like material – no other advantage (or disadvantage) was found. Results are discussed within the context of recent large-scale experimental and meta-analytic studies that have failed to find bilingual advantages in domain-general abilities such as attention control and working memory capacity in young adults.     

Effects of speed of word processing on semantic access: the case of bilingualism

Bilingual speakers generally manifest slower word recognition than monolinguals. We investigated the consequences of the word processing speed on semantic access in bilinguals. The paradigm involved a stream of English words and pseudowords presented in succession at a constant rate. English-Welsh bilinguals and English monolinguals were asked to count the number of letters in pseudowords and actively disregard words. They were not explicitly told that pairs of words in immediate succession were embedded and could either be semantically related or not. We expected that slower word processing in bilinguals would result in semantic access indexed by semantic priming. As expected, bilinguals showed significant semantic priming, indexed by an N400 modulation, whilst monolinguals did not. Moreover, bilinguals were slower in performing the task. The results suggest that bilinguals cannot discriminate between pseudowords and words without accessing semantic information whereas monolinguals can dismiss English words on the basis of subsemantic information.     

Phonological priming and cohort effects in toddlers

Adult word recognition is influenced by prior exposure to phonologically or semantically related words (cup primes cat or plate) compared to unrelated words (door), suggesting that words are organised in the adult lexicon based on their phonological and semantic properties and that word recognition implicates not just the heard word, but also related words. We investigate the phonological organisation of the toddler lexicon with two experiments using a picture priming technique. Twenty-four month olds showed inhibition of target recognition in related primed trials compared to unrelated primed trials (Experiment 1) and also in related primed trials compared to unprimed trials (Experiment 2). Further analysis of children’s responding found that this inhibition effect was modulated by the cohort and neighbourhood size of the words tested. Overall, the results indicate a lexical basis for the reported effects and suggest that the phonological properties provide an organisational basis for words in the toddler lexicon.     

On the masking and disclosure of unconscious elaborate processing. A reply to Van Opstal, Reynvoet, and Verguts (2005)

We have recently argued that unconscious numerical stimuli might activate responses by a match with prespecified action trigger codes (action trigger account) rather than by semantic prime processing (elaborate processing account). [Van Opstal, F., Reynvoet, B., and Verguts, T. (2005). How to trigger elaborate processing? A comment on Kunde, Kiesel, and Hoffmann (2003). Cognition] replicate one piece of evidence for our inference—an inefficiency of primes not presented in target format (verbal or Arabic). But this was found only with letter masks and not with hash masks. The authors conclude that letter masks block unconscious prime processing, and that elaborate processing can account for unconscious priming effects if all its (sometimes subtle) side conditions are considered. We agree that the type of mask in general is an important factor in priming studies but we note that (i) the authors' mask-blocking hypothesis is not well supported by the data, (ii) clear evidence for semantic prime processing in their study is lacking and, (iii) differences in mask efficiency (rather than mask type) might account for the conflicting results. To corroborate this inference we replicate van Opstal et al.'s results with letter masks but reduced mask efficiency. Altogether their data do not challenge the action-trigger account nor do they strongly support the elaborate processing view.     

How emotional pictures influence visuospatial binding in short-term memory in ageing and Alzheimer’s disease?

The present study examines the prediction that emotion can facilitate short-term memory. Nevertheless, emotion also recruits attention to process information, thereby disrupting short-term memory when tasks involve high attentional resources. In this way, we aimed to determine whether there is a differential influence of emotional information on short-term memory in ageing and Alzheimer's disease (AD). Fourteen patients with mild AD, 14 healthy older participants (NC), and 14 younger adults (YA) performed two tasks. In the first task, involving visual short-term memory, participants were asked to remember a picture among four different pictures (negative or neutral) following a brief delay. The second task, a binding memory task, required the recognition by participants of a picture according to its spatial location. The attentional cost involved was higher than for the first task. The pattern of results showed that visual memory performance was better for negative stimuli than for neutral ones, irrespective of the group. In contrast, binding memory performance was essentially poorer for the location of negative pictures in the NC group, and for the location of both negative and neutral stimuli in the AD group, in comparison to the YA group. Taken together, these results show that emotion has beneficial effects on visual short-term memory in ageing and AD. In contrast, emotion does not improve their performances in the binding condition.     

The role of form and meaning in the processing of written morphology: A priming study in French developing readers

Three visual priming experiments using three different prime durations (60 ms in Experiment 1, 250 ms in Experiment 2, and 800 ms in Experiment 3) were conducted to examine which properties of morphemes (form and/or meaning) drive developing readers’ processing of written morphology. French third, fifth, and seventh graders and adults (the latter as a control group) performed lexical decision tasks in which targets were preceded by morphological (e.g., tablette–TABLE, “little table–table”), pseudoderived (e.g., baguette–BAGUE, “little stick–ring”), orthographic control (e.g., abricot–ABRI, “apricot–shelter”), and semantic control (e.g., Tulipe–FLEUR, “tulip–flower”) primes. Across all groups, different patterns of priming were observed in both morphological and orthographic/semantic control conditions, suggesting that they all process morphemes as units when reading. In developing readers, the processing of written morphology is triggered by the form properties of morphemes, and their semantic properties are activated later in the time course of word recognition. In adults, patterns of priming were similar except that the activation of the form properties of morphemes decreased earlier in the time course of word recognition. Taken together, these findings indicate that French developing readers process both the form and meaning properties of morphemes when reading and support a progressive quantitative change in the development of morphological processing over the course of reading development.     

对感觉记忆在相同范畴视觉搜索中作用的研究

该文以三种字母卡片为刺激物,通过两种靶字母搜索实验,探讨了感觉记忆在相同范畴视觉搜索中的作用。实验结果显示,感觉记忆和短时记忆信息都可能利用时的搜索成绩,明显高于限用短时记忆信息时的搜索成绩。这表明,感觉记忆信息可以直接用于相同范畴的视觉搜索。