Understanding the mechanisms responsible for developmental dyslexia (DD) is a key challenge for researchers. A large literature, mostly concerned with learning to read in opaque orthographies, emphasizes phono-logical interpretations of the disturbance. Other approaches focused on the visual-per-ceptual aspects of orthographic coding. Recently, this perspective was supported by imaging data showing that individuals with DD have hypo-activation in occipito-temporal areas (a finding common to both transpar-ent and opaque orthographies). Nevertheless, it is difficult to infer causal relationships from activation data. Accommodating these findings within the cognitive architecture of reading processes is still an open issue. This is a general problem, which is present in much of the literature. For example, several studies investigating the perceptual and cognitive abilities that distinguish groups of children with and without DD failed to provide explicit links with the reading process. Thus, several areas of investigation (e.g., acoustic deficits or magnocellular deficiencies) have been plagued by replication failures. Furthermore, much research has neglected the possible contribution of comorbid symptoms. By contrast, it is now well established that developmental disorders present a large spectrum of homotopic and heterotopic co-morbidities that make causal interpretations problematic. This has led to the idea that the etiology of learning difficulties is multifactorial, thus challenging the traditional models of DD. Recent genetic studies provide information on the multiple risk factors that contribute to the genesis of the disturbance. Another critical issue in DD is that much of the research has been conducted in English-speaking individuals. However, English is a highly irregular orthography and doubts have been raised on the appropriateness of automatically extending interpretations based on English to other more regular orthographies. By contrast, important information can be gotten from systematic comparisons across languages. Thus, the distinction between regular and irregular orthographies is another potentially fruitful area of investigation. Overall, in spite of much research current interpretations seem unable to integrate all available findings. Some proposals focus on the cognitive description of the reading profile and explicitly ignore the distal causes of the disturbance. Others propose visual, acoustic or phonological mech-anisms but fail to link them to the pattern of reading impairment present in different children. The present Research Topic brings together studies based on different methodological approaches (i.e., behavioural studies examining cognitive and psycholinguistic factors, eye movement inves-tigations, biological markers, neuroimaging and genetic studies), involving dyslexic groups with and without comorbid symptoms, and in different orthographies (transparent and opaque) to identify the mechanisms underlying DD. The RT does not focus on a single model or theory of dyslexia but rather brings together different approaches and ideas which we feel are fruitful for a deeper understanding developmental dyslexia.

The chapters in this volume are based on presentations made at a recent conference on cognitive and linguistic foundations of reading acquisition. The researchers who participated have all made contributions to the theoretical and empirical understanding of how children learn to read. They were asked to address not only what they have learned from their research, but also to discuss unsolved problems. This dialogue prompted numerous questions of both a theoretical and applied nature, generated heated debate, and fueled optimism about the important gains that have been made in the scientific understanding of the reading process, especially of the critical role played by phonological abilities.

This book offers an interdisciplinary look at the acquisition, loss, and remediation of normal reading processes.

Over the last 25 years, reading processes have been the focus of an enormous amount of research in experimental psychology as well as in other disciplines. The theories and models emerging from this research have greatly advanced understanding of both normal acquisition and of reading disabilities. Although great progress has been made, there are certain aspects that have been relatively neglected in the current understanding. Specifically, the role of visual factors has received less attention than that of other component processes. This is particularly surprising since reading and writing are distinct from the other language processes of speaking and listening in large part by virtue of the fact that a visual dimension is involved. Relevant research is broadly scattered both geographically and in terms of disciplines, and there have been no major reviews or books concerned with the visual dimension of reading and reading disabilities. The purpose of this book is to bring together a broad range of evidence that concerns the role of visual information in reading and reading disabilities. Because reading processes are of central interest to cognitive scientists, neuropsychologists, psycholinguists, clinicians, and educators, this book should draw a very broad readership.

In this volume a group of well-known experts of the field cover topics ranging from basic visual and auditory information processing to higher order cognition in reading and dyslexia, from basic research to remediation approaches and from well-established theories to new hypotheses about reading acquisition and causes for its failure. Reading is one of the most intriguing feats human evolution ever came up with. There is no evolutionary basis for reading as such; reading is secondary to language and the result of a complex skill acquisition at the end of which almost all pre-existing cognitive functions are mobilized. With the right instruction and practice most people learn this skill smoothly. Some, however, have problems, despite same opportunities and general cognitive abilities. This developmental dyslexia results from a neuro developmental disorder leading to deficits in reading relevant information processing. But what deficits are these, and can they be trained?

Most studies on reading have been conducted with English-speaking subjects. It is crucial to also examine studies conducted in different languages, in order to highlight which aspects of reading acquisition and dyslexia appear to be language-specific, and which are universal. Reading Acquisition and Developmental Dyslexia sheds new light on dyslexia and its relationship with reading acquisition, presenting two unique advancements in this area. Looking at studies conducted in different languages, the prerequisites of reading acquisition are examined, and the findings from studies of skilled adult readers are presented. The manifestations of developmental dyslexia and the main contemporary explanations for it are outlined, providing an in-depth, well researched discussion of the topic. The authors conclude by offering a new framework which could explain both reading acquisition and developmental dyslexia. A fascinating book offering a unique insight into the topic of dyslexia, it will be of great interest to students and lecturers in cognitive psychology, educational psychology, and psycholinguistics, as well as those with a more everyday involvement with the disorder such as speech and language therapists.