A review of the neurobiological basis of dyslexia in the adult population. / Una revisión de las bases neurobiológicas de la dislexia en población adulta.

INTRODUCTION: Adult dyslexia affects about 4% of the population. However, studies on the neurobiological basis of dyslexia in adulthood are scarce compared to paediatric studies. AIM: This review investigates the neurobiological basis of dyslexia in adulthood. DEVELOPMENT: Using PsycINFO, a database of psychology abstracts, we identified 11 studies on genetics, 9 neurostructural studies, 13 neurofunctional studies and 24 neurophysiological studies. Results from the review show that dyslexia is highly heritable and displays polygenic transmission. Likewise, adult neuroimaging studies found structural, functional, and physiological changes in the parieto-occipital and occipito-temporal regions, and in the inferior frontal gyrus, in adults with dyslexia. CONCLUSION: According to different studies, aetiology in cases of adult dyslexia is complex. We stress the need for neurobiological studies of dyslexia in languages with transparent spelling systems.

[Research into learning disabilities: a documentary analysis]. / La investigación en dificultades de aprendizaje: un análisis documental

INTRODUCTION: Our current understanding of learning disabilities (LD) is essentially limited by their actual definition, the heterogeneity of the samples and the unsuitability of the control groups. AIMS: This study offers an overview of the methodological aspects and the areas of research in LD. DEVELOPMENT: From a bibliographical search conducted in the Psychological Abstracts database, PsycINFO, we identified and selected the studies the review was to focus on, and this was completed with previous reviews. Quantitative research methods are preferred in 99.7% of cases, whereas the remaining 0.3% opted for qualitative methods. There was in increase in the number of research reviews, as well as longitudinal studies and those aimed at determining the effectiveness of the interventions, with the resulting interest in new techniques for data analysis such as meta-analysis, path analysis and latent growth curves. The research topics that aroused most interest were LD-related problems (16.7%), difficulties in learning to read (15.82%), studies focusing on intervention (10.15%) and diagnostics in LD. CONCLUSIONS: The primary objectives of the research appear to be the characterisation of LD and the problems they cause throughout the patient's life cycle, together with their identification and early treatment. Research is also extended towards other, more practical matters, with a special emphasis on the school setting.

[Educational implications of the cognitive impairment in developmental dyslexia]. / Implicaciones educativas del deficit cognitivo de la dislexia evolutiva.

AIMS: In this study we review the main theories put forward to account for developmental dyslexia, as well as the intervention procedures deriving from these theories that enjoy the most empirical support. DEVELOPMENT: Developmental dyslexia is a complex disorder that reflects cognitive impairment related to neurobiological anomalies, although researchers still do not agree on fundamental aspects regarding its aetiology. There are at present a number of different theories that can be grouped in two antagonistic lines of work. On the one hand, one of them considers that the exclusive and direct cause of dyslexia is a specific cognitive disorder. On the other hand, however, there are several theories that consider the impairments experienced by dyslexic patients to be part of a wide range of tasks and processes that are secondary to an underlying primary deficit. As a consequence of the progress made in the characterisation of dyslexia, an unprecedented effort has been made in recent decades in the development of intervention programmes and in the analysis of their effectiveness. CONCLUSIONS: Research into the explanation for dyslexia finds itself faced with the challenge of determining whether the different cognitive problems identified in dyslexic patients represent different cognitive routes towards the same dyslexic phenotype, whether they correspond to different types of dyslexia or whether they refer to the sum of the problems resulting from different comorbid conditions. Until this issue is resolved, as educators, we must carry out more comprehensive evaluations in order to determine the profile of the difficulties that are experienced in each particular case and to be able to tailor the interventions employed in this enigmatic problem.

[Neurocognitive treatment for learning disabilities]. / Tratamiento neurocognitivo de las dificultades en el aprendizaje.

The present study examines the viability of an intervention model intended to develop cognitive and metacognitive strategies, by sel-instructional procedures. Furthermore the results of programs that explore the efficiency of this model in the interventions for students with learning disabilities (LD) are discussed. Finally, a number of guidelines for the future research in this area are included, underlining the importance of contextualizing the programs aimed in teaching to thinking.

[The application of new technologies to solving maths problems for students with learning disabilities: the 'underwater school']. / Aplicación de nuevas tecnologías con estudiantescon dificultades de aprendizaje en la solución deproblemas matemáticos: la 'escuela submarina'.

INTRODUCTION: Different procedures have demonstrated efficacy to teach cognitive and metacognitive strategies to problem solving in mathematics. Some studies have used computer-based problem solving instructional programs. AIM: To analyze in students with learning disabilities the efficacy of a cognitive strategies training for problem solving, with three instructional delivery formats: a teacher-directed program (T-D), a computer-assisted instructional (CAI) program, and a combined program (T-D + CAI). SUBJECTS AND METHODS: Forty-four children with mathematics learning disabilities, between 8 and 10 years old participated in this study. The children were randomly assigned to one of the three instructional formats and a control group without cognitive strategies training. In the three instructional conditions which were compared all the students learnt problems solving linguistic and visual cognitive strategies trough the self-instructional procedure. Several types of measurements were used for analysing the possible differential efficacy of the three instructional methods implemented: solving problems tests, marks in mathematics, internal achievement responsibility scale, and school behaviours teacher ratings. RESULTS AND CONCLUSIONS: Our findings show that the T-D training group and the T-D + CAI group improved significantly on math word problem solving and on marks in Maths from pre- to post-testing. In addition, the results indicated that the students of the T-D + CAI group solved more real-life problems and developed more internal attributions compared to both control and CAI groups. Finally, with regard to school behaviours, improvements in school adjustment and learning problems were observed in the students of the group with a combined instructional format (T-D + CAI).