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- Literacy: exploring working memory systemsPublication . Silva, Catarina; Faísca, Luís; Ingvar, Martin; Petersson, Karl Magnus; Reis, AlexandraPrevious research showed an important association between reading and writing skills (literacy) and the phonological loop. However, the effects of literacy on other working memory components remain unclear. In this study, we investigated performance of illiterate subjects and their matched literate controls on verbal and nonverbal working memory tasks. Results revealed that the phonological loop is significantly influenced by literacy, while the visuospatial sketchpad appears to be less affected or not at all. Results also suggest that the central executive might be influenced by literacy, possibly as an expression of cognitive reserve.
- Semantic interference on a phonological task in illiterate subjectsPublication . Reis, Alexandra; Faísca, Luís; Mendonca, Susana; Ingvar, Martin; Petersson, Karl MagnusScandinavian Journal of Psychology, 2007, 48, 69–74 DOI: 10.1111/j.1467-9450.2006.00544.x © 2007 The Authors. Journal compilation © 2007 The Scandinavian Psychological Associations. Published by Blackwell Publishing L td., 9600 Garsington Road, Oxford OX4 2DQ, UK and 350 Main Street, Malden, MA 02148, USA. ISSN 0036-5564. Blackwell Publishing Ltd Health and Disability Semantic interference on a phonological task in illiterate subjects ALEXANDRA REIS, 1,2,3 L UÍS FAÍSCA, 2,3 SUSANA MENDONÇA, 2 MARTIN INGVAR 1 and KARL MAGNUS PETERSSON 1,3,4 1 Cognitive Neurophysiology Research Group, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden 2 Cognitive Neuroscience Research Group, Departamento de Psicologia, Faculdade de Ciências Humanas e Sociais, Universidade do Alg arve, Faro, Por tugal 3 Center for Intelligent Systems, Universidade do Algarve, Faro, Portugal 4 F. C. Donders Centre for Cognitive Neuroimaging, Radboud University Nijmegen, The Netherlands R eis, A., Faísca, L., Mendonça, S., Ingvar, M. & Petersson, K. M. (2007). Semantic interference on a phonological task in illit erate subjects. Scandinavian Journal of Psychology , 48 , 69–74. Previous research suggests that learning an alphabetic written language influences aspects of the auditory-verbal language syste m. In this study, we e xamined whether literacy influences the notion of words as phonological units independent of lexical semantics in literate a nd illiterate subjects. Subjects had to decide which item in a word- or pseudoword pair was phonologically longest. By manipulating the relat ionship between r eferent size and phonological length in three word conditions (congruent, neutral, and incongruent) we could examine to what e xtent subjects f ocused on form rather than meaning of the stimulus material. Moreover, the pseudoword condition allowed us to examine global p honological aw areness independent of lexical semantics. The results showed that literate performed significantly better than illiterate subj ects in the neutral and incongruent word conditions as well as in the pseudoword condition. The illiterate group performed least well in the incong ruent condition and significantly better in the pseudoword condition compared to the neutral and incongruent word conditions and suggest that pe rformance on phonological word length comparisons is dependent on literacy. In addition, the results show that the illiter a te participant s are able to perceive and process phonological length, albeit less well than the literate subjects, when no semantic interference is present . In conclusion, the present results confirm and extend the finding that illiterate subjects are biased towards semantic-conceptual-pragmatic type s of cognitive processing
- Changes in social emotion recognition following traumatic frontal lobe injuryPublication . Martins, Ana Teresa; Faísca, Luís; Esteves, Francisco; Simão, Cláudia; Justo, M. G.; Muresan, A.; Reis, AlexandraChanges in social and emotional behaviour have been consistently observed in patients with traumatic brain injury. These changes are associated with emotion recognition deficits which represent one of the major barriers to a successful familiar and social reintegration. In the present study, 32 patients with traumatic brain injury, involving the frontal lobe, and 41 age- and education-matched healthy controls were analyzed. A Go/No-Go task was designed, where each participant had to recognize faces representing three social emotions (arrogance, guilt and jealousy). Results suggested that ability to recognize two social emotions (arrogance and jealousy) was significantly reduced in patients with traumatic brain injury, indicating frontal lesion can reduce emotion recognition ability. In addition, the analysis of the results for hemispheric lesion location (right, left or bilateral) suggested the bilateral lesion sub-group showed a lower accuracy on all social emotions.
- Formal schooling influences two- but not three-dimensional naming skillsPublication . Reis, Alexandra; Magnus Petersson, Karl; Castro-Caldas, A.; Ingvar, MartinThe modulatory influence of literacy on the cognitive system of the human brain has been indicated in behavioral, neuroanatomic, and functional neuroimaging studies. In this study we explored the functional consequences of formal education and the acquisition of an alphabetic written language on two- and three-dimensional visual naming. The results show that illiterate subjects perform significantly worse on immediate naming of two-dimensional representations of common everyday objects compared to literate subjects, both in terms of accuracy and reaction times. In contrast, there was no significant difference when the subjects named the corresponding real objects. The results suggest that formal education and learning to read and to write modulate the cognitive process involved in processing two- but not three-dimensional representations of common everyday objects. Both the results of the reaction time and the error pattern analyses can be interpreted as indicating that the major influence of literacy affects the visual system or the interaction between the visual and the language systems. We suggest that the visual system in a wide sense and/or the interface between the visual and the language system are differently formatted in literate and illiterate subjects. In other words, we hypothesize that the pattern of interactions in the functional-anatomical networks subserving visual naming, that is, the interactions within and between the visual and language processing networks, differ in literate and illiterate subjects. (C) 2001 Elsevier Science.
- When the eyes no longer lead: familiarity and length effects on eye-voice spanPublication . Silva, Susana; Reis, Alexandra; Casaca, Luís; Petersson, Karl Magnus; Faísca, LuísDuring oral reading, the eyes tend to be ahead of the voice (eye-voice span, EVS). It has been hypothesized that the extent to which this happens depends on the automaticity of reading processes, namely on the speed of print-to-sound conversion. We tested whether EVS is affected by another automaticity component - immunity from interference. To that end, we manipulated word familiarity (high-frequency, low-frequency, and pseudowords, PW) and word length as proxies of immunity from interference, and we used linear mixed effects models to measure the effects of both variables on the time interval at which readers do parallel processing by gazing at word N + 1 while not having articulated word N yet (offset EVS). Parallel processing was enhanced by automaticity, as shown by familiarity x length interactions on offset EVS, and it was impeded by lack of automaticity, as shown by the transformation of offset EVS into voice eye span (voice ahead of the offset of the eyes) in PWs. The relation between parallel processing and automaticity was strengthened by the fact that offset EVS predicted reading velocity. Our findings contribute to understand how the offset EVS, an index that is obtained in oral reading, may tap into different components of automaticity that underlie reading ability, oral or silent. In addition, we compared the duration of the offset EVS with the average reference duration of stages in word production, and we saw that the offset EVS may accommodate for more than the articulatory programming stage of word N.
- Distinguishing cause from effect - many deficits associated with developmental dyslexia may be a consequence of reduced and suboptimal reading experiencePublication . Huettig, Falk; Lachmann, Thomas; Reis, Alexandra; Petersson, Karl MagnusThe cause of developmental dyslexia is still unknown despite decades of intense research. Many causal explanations have been proposed, based on the range of impairments displayed by affected individuals. Here we draw attention to the fact that many of these impairments are also shown by illiterate individuals who have not received any or very little reading instruction. We suggest that this fact may not be coincidental and that the performance differences of both illiterates and individuals with dyslexia compared to literate controls are, to a substantial extent, secondary consequences of either reduced or suboptimal reading experience or a combination of both. The search for the primary causes of reading impairments will make progress if the consequences of quantitative and qualitative differences in reading experience are better taken into account and not mistaken for the causes of reading disorders. We close by providing four recommendations for future research.
- Electrophysiological evidence for colour effects on the naming of colour diagnostic and noncolour diagnostic objectsPublication . Bramão, Inês; Francisco, Ana; Inácio, Filomena; Faísca, Luís; Reis, Alexandra; Petersson, Karl MagnusIn this study, we investigated the level of visual processing at which surface colour information improves the naming of colour diagnostic and noncolour diagnostic objects. Continuous electroencephalograms were recorded while participants performed a visual object naming task in which coloured and black-and-white versions of both types of objects were presented. The black-and-white and the colour presentations were compared in two groups of event-related potentials (ERPs): (1) The P1 and N1 components, indexing early visual processing; and (2) the N300 and N400 components, which index late visual processing. A colour effect was observed in the P1 and N1 components, for both colour and noncolour diagnostic objects. In addition, for colour diagnostic objects, a colour effect was observed in the N400 component. These results suggest that colour information is important for the naming of colour and noncolour diagnostic objects at different levels of visual processing. It thus appears that the visual system uses colour information, during naming of both object types, at early visual stages; however, for the colour diagnostic objects naming, colour information is also recruited during the late visual processing stages.
- Cognitive subtyping of university students with dyslexia in a semi-transparent orthography: what can weaknesses and strengths tell us about compensation?Publication . Faisca, Luis; Reis, Alexandra; Araújo, SusanaDevelopmental dyslexia is characterized by a profile of reading- and writing-related difficulties which stands out as a core deficit in phonological processing. Although these difficulties seem to persist into adulthood, it is still an open question to what extent they are immune, or not, to the extensive training resulting from extended schooling. The main objective of this study was to explore the heterogeneity of the cognitive profile of European Portuguese highly literate adults with dyslexia. Thirty-one university students diagnosed with dyslexia during childhood and their matched skilled adult control readers were assessed through a battery of reading and cognitive tests. A cluster analysis of data obtained from participants with dyslexia identified two profile groups. While Cluster 1 grouped participants with clear phonological deficits and concomitant reading difficulties, Cluster 2 showed better performance on most of the core skills associated with reading and also better general cognitive abilities, suggesting that these dyslexic readers have partially resolved their phonological constraints along the development, probably due to the systematic exposure to reading and writing. As Cluster 2 matched typical readers in general cognitive abilities, it might also be the case that cognitive strengths associated with general intelligence worked as protective factors, helping students to strategically compensate for their reading difficulties. Overall, these results suggest that both mechanisms-partial remediation of the core phonological deficit and adoption of compensatory strategies supported by general cognitive skills-might contribute together to improving the reading performance of highly literate adults with dyslexia.
- Component processes subserving rapid automatized naming in dyslexic and non-dyslexic readersPublication . Araújo, Susana; Inácio, Filomena; Francisco, Ana; Faísca, Luís; Petersson, Karl Magnus; Reis, AlexandraThe current study investigated which time components of rapid automatized naming (RAN) predict group differences between dyslexic and non-dyslexic readers (matched for age and reading level), and how these components relate to different reading measures. Subjects performed two RAN tasks (letters and objects), and data were analyzed through a response time analysis. Our results demonstrated that impaired RAN performance in dyslexic readers mainly stem from enhanced inter-item pause times and not from difficulties at the level of post-access motor production (expressed as articulation rates). Moreover, inter-item pause times account for a significant proportion of variance in reading ability in addition to the effect of phonological awareness in the dyslexic group. This suggests that non-phonological factors may lie at the root of the association between RAN inter-item pauses and reading ability. In normal readers, RAN performance was associated with reading ability only at early ages (i.e. in the reading-matched controls), and again it was the RAN inter-item pause times that explain the association.
- Does emotional valence modulate word recognition? A behavioral study manipulating frequency and arousalPublication . Paulino, Catarina; Guerreiro, Milene; Faisca, Luis; Reis, AlexandraEffects of emotional valence have been observed in lexical decision tasks, suggesting that valence information modulates early word recognition. However, is still unclear the processing advantage of the different valence categories, and how these advantages might be modulated by word frequency and arousal. To clarify this question, a lexical decision task was designed using emotional words as stimuli. Emotional words were divided into three categories: 60 positive, 60 negative, and 60 neutral words. Word frequency was manipulated into low and high conditions and arousal was controlled among experimental conditions (word valence and frequency). In the first experiment, 54 participants performed the task with a maximum stimuli exposure time of 2000 ms. In a follow-up experiment, 42 participants performed the same task with two shorter fixed time exposures (150 ms and 300 ms). The results were similar between experiments: positive words were recognized faster and negative words were recognized slower than neutral ones. Furthermore, this valence effect was modulated by word frequency, affecting only words that take longer to be recognized (low-frequency words). However, the valence by frequency interaction was attenuated for high-arousal words when the pressure to respond was high (short exposure time - 150 ms). Overall, the results confirm that the emotional status of a word can affect word processing at early stages when automatic processes are taking place.