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Title: Fluency in Reading Subtitle: Synchronization of Processes Author: Zvia Breznitz Published: 2006 Publisher: Lawrence Erlbaum Associates
Reviewer: Prisca Stenneken, Prof. i.K. Dr., Department of Physiological and Clinical Psychology, Cath. University of Eichstaett-Ingolstadt, Germany
INTRODUCTION This monograph covers the issue of reading fluency. Theoretical considerations are applied to mechanisms of normal reading and to developmental disorders of written language processing (dyslexia). The main focus of the book is on the crucial role of the speed of information processing in the brain in determining reading fluency. With the Synchronization Hypothesis, the author argues that accurate integration of information in word reading (especially in word decoding) can occur only when the modalities (e.g. auditory or visual processing modality) and brain systems are in synchronization with each other. Thus, developmental dyslexia is assumed to arise from ineffective temporal coordination of all the components that participate in the process of translating artificial printed symbols into meaning. As a basis for this hypothesis, the book provides an extensive overview of the various theoretical concepts (e.g., reading rate, automaticity, prosody, and naming speed) and a discussion of behavioral and electrophysiological (ERP) findings related to fluency in reading. The book is intended for researchers and advanced students in the fields of cognitive linguistics, psychology and neuropsychology, with focus in reading research. It may also provide in-depth information on theoretical concepts that form the basis of clinical-practical work with dyslexic readers. The author, Prof. Dr. Zvia Breznitz, is Head of the Department of Learning Disabilities and Director of the Laboratory for Neurocognitive Research at Haifa University in Israel. Zvia Breznitz is known to researchers in the field by her long history of research and empirical investigations in the area of reading fluency.
SUMMARY AND EVALUATION The author develops her theoretical concept of reading fluency in the course of the 14 book chapters which she assigns to three main parts: (1) Description of word reading fluency, (2) The determinants of word reading fluency, and (3) The ''Sychronization Hypothesis''.
Part I: Description of Word Reading Fluency. The first five chapters explain relevant theoretical concepts related to the fluency in reading, which is discussed from both traditional and modern perspectives. In contrast to the more traditional view of reading fluency as a convenient measure of reading skills, the author argues that fluency has a strong impact on other aspects of reading and plays a central role in the entire reading process. After giving an introduction to reading fluency and the factor 'reading rate', the author discusses the topics of automaticity in reading, prosody, and naming speed. This extensive and multi-face ted overview is a great strength of this book. In addition, these introductory chapters contribute to the methodological understanding of the topic. This methodological approach focuses on the fact that reading rate, as the central factor in fluent word reading, can either be regarded as a dependent or independent variable: Depending on the theoretical standpoint, reading accuracy and comprehension can either be regarded as underlying processes of reading rate, or - as the author suggests - as being affected by reading rate. Thus, these first chapters also point to the methodological implications for future research in reading fluency.
Part II: The Determinants of Word Reading Fluency. The second part of the book deals with the determinants of reading fluency. Among these, the main focus is on the speed of information processing in the brain. In two chapters, the author gives a systematic and detailed description of the two processing modalities relevant for reading, i.e. the visual and the auditory-phonological modality. Reference is made to the basic theoretical concepts, the physiology and the relevant brain structures, and the underlying mechanisms in normal reading. In addition, the chapters discuss the different explanatory accounts of deficits in reading fluency that relate to visual or auditory-phonological processing. Here, as the author acknowledges, it is sometimes difficult to disentangle accounts that make reference to lower level perceptual processes vs. higher, linguistic level, processes. Based on these theoretical considerations the author reviews extensive empirical evidence from her lab. These research projects by Breznitz and colleagues investigated different stages of information processing in normal and dyslexic reading, including a behavioral study and a study using the measures of Event-Related Potentials (ERPs) that are described in more detail. In sum, the empirical studies by Breznitz and colleagues demonstrated that dyslexic readers were slower than regular readers at each stage of activation in the word decoding process in each modality and system. In relating the findings to the complex issues of cross-modal integration the author argues that the word decoding impairment in dyslexic readers can be attributed to deficient synchronization in the speed of processing of the modalities and the systems involved in reading. In addition, the author claims that dyslexic readers are less able to identify word patterns, as these were not appropriately stored in the mental lexicon. As a consequence, this would further slow down the already slow speed of processing. For the more detailed specification of the hypothesis, the reader is referred to the following chapters.
Part III: The ''Sychronization Hypothesis''. The final part of the book comprises three chapters which illustrate the Synchronization Hypothesis and discuss the role of the asynchrony phenomenon as a major factor in dyslexia. As has been proposed in earlier studies of the author (e.g., Breznitz, 2001, 2003; Breznitz & Misra, 2003), a slow speed of processing is assumed as the general underlying cause of dyslexia. In more detail, the speed of processing of the various components involved in reading is not sufficiently coordinated in dyslexia. Here, the author relates back to the concept of the word decoding rate which is determined by two factors: 1. by the characteristics of the information processing system, and 2. by the speed of processing of the modalities and the systems involved in reading. Consequently, the author argues for the relevance to measure the speed of processing of the visual and the auditory modalities as well as cross modal integration in regular and dyslexic readers. Additional empirical evidence is provided, using the method of computing cross-modality gap scores from different sets of single-modality experiments. Finally, the author presents an intervention study which manipulated the reading rate by means of the acceleration method. It is assumed that, under time constraints, lexical access may be based on a holistic, orthographic word pattern. Thus according to the author, the acceleration method may force the dyslexic readers to rely more strongly on this strategy and less so on the impaired phonological system. In sum, this method is suggested as a possible intervention technique to prompt the (dyslexic) brain to process graphemic information more effectively. Based on this piece of evidence, future studies could show how this technique can be applied in a broader context and to different orthographies. In contrast to many previous accounts of dyslexia, the present approach does not aim to specify a single deficient mechanism underlying the dyslexic disorder. It rather focuses on the complex (temporal) interplay of the various structures involved in the reading process. As a consequence, it does not allow to specify the relative contributions of, for example, different sub-components in the reading process, of the auditory vs. the visual modalities, or of higher level vs. lower level mechanisms in the ''information processing system''.
CONCLUSION: The book posits a new approach to reading fluency in dyslexia, based on the view that effective reading requires synchronization of the different brain systems. The synchronization hypothesis is developed from an extensive description of the relevant theoretical concepts and a discussion of supportive empirical evidence. The author gives an expanded view of reading fluency in discussing the concept as both a dependent and an independent variable. By presenting wide-ranging empirical evidence, including ERP measures, the present book contributes to the often claimed converging methods approach. In addition, some ideas are presented for research-based intervention procedures to enhance reading fluency.
References: Breznitz, Z. (2001). The determinants of reading fluency: A comparison of dyslexic and average readers. In M. Wolf (Ed.), Dyslexia, fluency and the brain (pp.245-276). Cambridge, MA: York Press. Breznitz, Z. (2003). Speed of phonological and orthographic processing as factors in dyslexia: Electrophysiological evidence. Genetic, Social and General Psychology Mongraphs, 129(2), 183-206. Breznitz, Z. & Misra, A. (2003). Speed of processing of the visual-orthographic and auditory-phonological systems in adult dyslexics: The contribution of ''asynchrony'' to word recognition deficits. Brain and Language, 85(3), 486-502.
ABOUT THE REVIEWER:
ABOUT THE REVIEWER
Prisca Stenneken, educated in (Neuro-)Linguistics and Psychology,
temporarily holds the chair in Physiological and Clinical Psychology (Cath.
University Eichstaett-Ingolstadt, Germany). Her main field of research is
language production and perception in relation to other cognitive
functions. Her focus is on the empirical investigation of disorders in
written and spoken language, involving developmental deficits and acquired
neuropsychological impairments. In current projects, she has conducted
experimental studies on disorders of reading and its underlying mechanisms,
like spatial, attentional and lexical processing.