Developmental Disorders of Language Learning and Cognition E-Book

Charles Hulme

• Herausgeber: John Wiley & Sons
• Kategorie: Geisteswissenschaft
• Sprache: Englisch

Seitenzahl: 959

Veröffentlichungsjahr: 2013

Beschreibung

This important new text is a comprehensive survey of current thinking and research on a wide range of developmental disorders.

• Highlights key research on normal and typical development
• Includes clinical case studies and diagrams to illustrate key concepts
• A reader-friendly writing style

Leseprobe

This edition first published 2009

© 2009 Charles Hulme and Margaret J. Snowling

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Library of Congress Cataloging-in-Publication Data

Hulme, Charles.

Developmental disorders of language learning and cognition / Charles Hulme and Margaret J. Snowling.

p. cm.

Includes bibliographical references and index.

ISBN 978-0-631-20611-8 (hardcover : alk. paper) – ISBN 978-0-631-20612-5 (pbk. : alk. paper)

1. Developmental disabilities. 2. Language disorders in children. 3. Cognition disorders in children.

I. Snowling, Margaret J. II. Title.

RJ506.D47H85 2009

618.92´855–dc22

2008044391

A catalogue record for this book is available from the British Library

1 2009

Contents

List of Plates

List of Figures

List of Boxes

Acknowledgments

1 Understanding Developmental Cognitive Disorders

Some Terminology for Classifying Cognitive Disorders

Levels of Explanation in Studies of Developmental Cognitive Disorders

Genetic Mechanisms

The Causes of Development – Nature Working with Nurture

Brain Mechanisms

Separable Systems in the Mind – Modularity and Development

The Need to Relate Developmental Disorders to Patterns of Typical Development

Categorical versus Dimensional Views of Developmental Disorders

Methods of Study in Developmental Cognitive Disorders

Establishing the Causes of Developmental Disorders

Comorbidity and Separating Causes from Correlates

Summary and Conclusions

2 Reading Disorders I: Developmental Dyslexia

Reading Disorders in Children: Definitions and Prevalence

The Normal Development of Literacy: A Theoretical Framework

The Pattern of Reading Impairment in Dyslexia

Are there Different Types of Dyslexia in Childhood?

Dyslexia in Different Languages

Cognitive Explanations of Developmental Dyslexia

Etiology of Dyslexia

A Cognitive Theory of Dyslexia

Treating Dyslexia

Chapter Summary

3 Reading Disorders II: Reading Comprehension Impairment

Definition and Prevalence

The Development of Reading Comprehension: A Theoretical Framework

The Pattern of Reading Impairment in Poor Comprehenders

Cognitive Explanations of Reading Comprehension Impairment

Longitudinal Studies of Children with Reading Comprehension Impairment

Summary of Core Cognitive Deficits and Likely Causes of Reading Comprehension Impairment

Etiology of Reading Comprehension Impairment

Interventions for Reading Comprehension Impairment

Summary and Conclusions

4 Specific Language Impairment

Definition and Prevalence

The Persistence of SLI

Comorbidities between SLI and Other Developmental Disorders

The Typical Development of Language: A Theoretical Framework

Language Development in Children with SLI

Linguistic and Cognitive Theories of SLI

The Etiology of SLI

Treatment of SLI

Summary and Conclusions

5 Mathematics Disorder

Definitions and Prevalence

The Typical Development of Number Skills: A Theoretical Framework

The Typical Development of Early Arithmetic Skills

The Nature of Arithmetic Difficulties in Children with Mathematics Disorder

Cognitive Bases of Difficulties in Children with Mathematics Disorder

The Etiology of Mathematics Disorder

Interventions to Improve Mathematics

Summary and Conclusions

6 Developmental Coordination Disorder

Definitions and Prevalence

The Persistence of DCD

Comorbidities between DCD and Other Developmental Disorders

The Typical Development of Motor Skills: A Theoretical Framework

The Nature of Movement Difficulties in Children with DCD

Cognitive Explanations of DCD

A Cognitive-Perceptual Theory of DCD: DCD as a Noisy Sensorimotor Map

Etiology

A Biological/Cognitive Model of DCD

The Treatment of DCD

Summary and Conclusions

7 Attention Deficit Hyperactivity Disorder

ADHD: Definition and Prevalence

Comorbidities between ADHD and Other Developmental Disorders

The Assessment of ADHD

The Nature of Executive Control/Behavioral Inhibition and their Typical Development

Cognitive Theories of ADHD

Motivational Theories of ADHD

ADHD Subtypes: Different Etiologies for Inattention and Hyperactivity?

The Role of Comorbidities in Accounting for some Symptoms of ADHD

Etiology of ADHD

Interventions for ADHD

Towards a Neurocognitive Theory of ADHD

8 Autism

Definition and Prevalence

Comorbidities with Other Developmental Disorders

Assessment and Diagnosis

Theories of Autism

The Typical Development of Social Interaction

Cognitive Theories of Autism

Etiology of Autism

Autism Outcomes and Treatments

Towards a Theory of Autism

Autism and Emotion: A Role for Noncognitive Factors

Summary and Conclusions

9 Understanding Developmental Cognitive Disorders: Progress and Prospects

Understanding Disorders Depends on Understanding Development

Development Depends upon Genes and Environments

Risks are Continuous and Disorders are Dimensional

Multiple Risks: Resilience and Compensation

Are Risks and Disorders Specific?

Comorbidity

Separate Risks or Overlapping Interacting Risks?

Environmental Influences on Developmental Cognitive Disorders

Whither (or Wither?) a Cognitive Perspective on Developmental Cognitive Disorders?

Dimensional Comorbid Disorders: Implications for Assessment and Treatment

Achievements and Aspirations for Understanding Developmental Cognitive Disorders

Glossary

References

Subject Index

Author Index

List of Plates

Plate 1 A magnetoencephalography (MEG) scanner in use.

Plate 2 Images from fMRI scans showing the major areas that are activated during reading aloud.

Plate 3 Relationship between gray matter density increases and reading performance in people with dyslexia.

Plate 4 Patterns of brain activity revealed by positron emission tomography (PET) in typical readers and adults with dyslexia during a short-term memory task and a rhyme judgment task.

Plate 5 Brain regions implicated in number processing and arithmetic based on brain imaging data.

Plate 6 Patterns of brain activation during approximate calculation, exact calculation, and magnitude comparison tasks in children with mathematics disorder (labeled MD) and normally developing children.

List of Figures

Figure 1.1 A causal model of the potential gene–brain–cognition–behavior pathways from MAOA-L to reactive aggression.

Figure 1.2 Diagram showing the complexities of genetic mechanisms.

Figure 1.3 Waddington’s epigenetic landscape is a metaphor for how gene regulation processes modulate development.

Figure 1.4 A phrenological head showing areas labeled with their supposed functions.

Figure 1.5 A computer as an example of a modular system.

Figure 1.6 The hippocampus: a bilateral mid-brain structure that plays a critical role in memory function.

Figure 1.7 Modular systems underlying the comprehension and production of spoken words in adults.

Figure 1.8 Two alternative causal theories of the association between smoking and lung cancer.

Figure 1.9 A path diagram showing a more detailed causal theory of the processes that mediate the effects of smoking on the development of lung cancer.

Figure 1.10 A reproduction of one of Sewall Wright’s earliest path diagrams (Wright, 1920) showing the effects of genetic and environmental influences on the pattern of coat color seen in guinea pigs.

Figure 2.1 Stage models of reading development.

Figure 2.2 A simple diagram of the letter string CAT with arrows from the letters to the phonemes in the spoken word /k/ /æ/ /t/.

Figure 2.3 The Triangle model of Seidenberg and McClelland (1989).

Figure 2.4 Path model showing the primary cause of dyslexia.

Figure 2.5 Elaborated path model showing causes of dyslexia.

Figure 2.6 The relationship between speech rate and memory span across development.

Figure 2.7 The relationship between speech rate and memory span in children of low, average, and high reading ability.

Figure 2.8 Path diagram showing phonological deficits as mediators of poor reading.

Figure 2.9 Path diagram showing a possible causal role of speech perception deficits in the development of reading problems.

Figure 2.10 Graph showing categorical perception for [ba] versus [pa].

Figure 2.11 Path diagram showing a possible causal role of an auditory perceptual deficit in the development of reading problems.

Figure 2.12 Path diagram showing putative causes of dyslexia.

Figure 2.13 Schematic diagram showing the major lobes of the brain and Broca’s and Wernicke’s areas.

Figure 2.14 Neural network model of reading implemented by Harm and Seidenberg (1999).

Figure 2.15 A path model of dyslexia showing a phonological deficit as the single proximal cause of a number of behavioral manifestations of dyslexia.

Figure 2.16 A path model of dyslexia showing separate deficits in phonology and speed of processing as causes of the behavioral manifestations of dyslexia.

Figure 3.1 The Simple View of Reading model.

Figure 3.2 Longitudinal predictors of reading comprehension.

Figure 3.3 Processes involved in text comprehension.

Figure 3.4 The Triangle model of Seidenberg and McClelland.

Figure 3.5 Path diagram showing causes of reading comprehension impairment.

Figure 3.6 Illustration of an ERP experiment conducted by Landi and Perfetti (2007) to investigate semantic processing.

Figure 3.7 Path diagram showing listening comprehension impairments as a mediator of reading comprehension impairments.

Figure 3.8 Path diagram showing separable causes of reading comprehension impairments.

Figure 3.9 Diagram illustrating multiple genetic influences on reading comprehension.

Figure 3.10 Path model showing possible sources of reading comprehension deficits.

Figure 4.1 Relationship between literacy skills and educational attainments in young people with a history of language impairment.

Figure 4.2 Cartoon illustrating pragmatic difficulties.

Figure 4.3 Growth in productive vocabulary for children rated as having an average vocabulary size and for those at the 90th centile (high) and the 10th centile (low).

Figure 4.4 Number of 5-year-old children producing different proportions of tense markers correctly.

Figure 4.5 Illustration of past tense generation task.

Figure 4.6 Schematic illustration of the stimuli used to assess amplitude envelope onset rise time.

Figure 4.7 New word learning by children with SLI and controls.

Figure 4.8 A path model for SLI.

Figure 5.1 Examples of the types of questions used in a standardized arithmetic test.

Figure 5.2 A chimpanzee in the study by Rumbaugh et al. (1987) selects a tray containing the larger number of food items.

Figure 5.3 Subitizing: Reaction time is fast in identifying between one and three items but increases steeply thereafter.

Figure 5.4 The time taken by 6-year-old typically developing children to judge which of two simultaneously presented digits represents the larger quantity (for digits 2–9).

Figure 5.5 A diagram of the mental number line.

Figure 5.6 Diagram of Baddeley’s working memory model.

Figure 5.7 The numerosity adaptation task used by Cantlon et al. (2006).

Figure 5.8 A path model of mathematics disorder.

Figure 6.1 A child completing some of the tasks from the Movement ABC.

Figure 6.2 The stepping reflex in an infant.

Figure 6.3 Picture of Hopi infant bound to a cradle board.

Figure 6.4 The effects of prismatic distortions on the control of pointing.

Figure 6.5 Diagram showing key areas of frontal and parietal cortex in the macaque monkey brain concerned with motor control.

Figure 6.6 Diagram of human mirror neuron system.

Figure 6.7 Diagram of the task developed by von Hofsten and Rosblad (1988).

Figure 6.8 An illustration of the experimental set-up used for the assessment of visual, kinesthetic, and cross-modal perception by Hulme et al. (1982).

Figure 6.9 The kinesthetic acuity apparatus used by Laszlo and Bairstow (1985a).

Figure 6.10 A swinging room apparatus.

Figure 6.11 A path model for developmental coordination disorder.

Figure 7.1 The Tower of Hanoi.

Figure 7.2 A problem-solving framework for understanding executive functions.

Figure 7.3 Distribution of reaction times in ADHD.

Figure 7.4 Theoretical delay-of-reinforcement gradients for ADHD (solid line) and controls (dotted line).

Figure 7.5 Profiles of groups with RD (dyslexia), ADHD, and comorbid RD + ADHD on tests of inhibition, set-shifting, working memory, and phoneme awareness.

Figure 7.6 Schematic diagram showing basal ganglia.

Figure 7.7 Dual-deficit theory of ADHD.

Figure 7.8 Path diagram showing a possible biological model of the origins of ADHD.

Figure 8.1 Picture of mother and child in triadic interaction.

Figure 8.2 Illustration of the Sally Anne task.

Figure 8.3 Experimental set-up for the windows task.

Figure 8.4 Illustration of Block Design in segmented and unsegmented form.

Figure 8.5 Response times for visual search for target present (left panel) and target absent (right panel) trials for group with autism (open symbols) and a control group (filled symbols).

Figure 8.6 Location of key brain regions that show activation during social cognition.

Figure 8.7 A path model of autism.

Figure 8.8 Path model illustrating the fractionation of the autism triad.

Figure 9.1 Diagram showing the overlap between autism, pragmatic language impairment, and Asperger syndrome.

Figure 9.2 Two-dimensional model of nonverbal learning difficulties.

Figure 9.3 Path model showing uncorrelated risk factors for separate disorders.

Figure 9.4 Classification showing four possible combinations of dyslexia and speech–language impairment.

Figure 9.5 Model of the causes of SLI.

Figure 9.6 Graph showing two normal distributions of reading ability.

Figure 9.7 Path diagram showing that smoking causes cancer.

Figure 9.8 Path diagram showing that lung cell mutations mediate the effects of smoking.

List of Boxes

Box 2.1 The nature of phonological skills.

Box 2.2 A longitudinal study of normal reading development.

Box 2.3 Effect sizes and meta-analysis.

Box 2.4 Illustration of orthography–phonology mappings in normal and atypical reading development.

Box 3.1 Grammar and morphology.

Box 3.2 Story schema.

Box 3.3 Examples of working memory tasks.

Box 3.4 The memory updating task.

Box 3.5 Examples of narratives varying in event structure.

Box 3.6 Examples of different inference types.

Box 3.7 Growth in reading in poor comprehenders and poor decoders.

Box 4.1 Speech perception.

Box 4.2 Pinker’s word-specific and general paradigms for inflections.

Box 4.3 Grammatical marking of finite verbs.

Box 5.1 Corsi blocks.

Box 5.2 Gerstmann syndrome.

Box 5.3 Approximate calculation, exact calculation, and magnitude comparison tasks.

Box 6.1 The human visual cortex.

Box 7.1 ADHD: Diagnosis and Symptomatology.

Box 7.2 The Wisconsin Card Sorting Task.

Box 7.3 The Stop-Signal Task.

Box 7.4 Randomized controlled trials.

Box 8.1 Examples of interview questions from the 3Di (Skuse et al., 2004) relating to each part of the triad.

Box 8.2 The ID/ED task.

Box 8.3 Coherent motion and contrast sensitivity tasks.

Box 8.4 The “Knock-Tap” task.

Acknowledgments

We are indebted to a huge number of friends and colleagues who helped and supported us during the time it has taken to write this book. Many collaborators, old and new, provided critical comments on the manuscript at various stages, notably Paula Clarke, Debbie Gooch, Sue Leekam, Helen Likierman, Valerie Muter, Kate Nation, Linda Pring, Silke Goebel, David Sugden and Eric Taylor. We were also extremely lucky that two of the most eminent scholars in the field, Dorothy Bishop and Michael Rutter, each read the entire manuscript and provided incisive and challenging comments. Our illustrator Dean Chesher did a fantastic job, always remaining positive and calm in the face of the many requests we made for amendments to the figures. We are grateful to members of our research group in the Centre for Reading and Language who either commented on chapters or helped in the final stages of revising them: Leesa Clarke, Piers Dawes, Fiona Duff, Lorna Hamilton, Becky Larkin, Emma Hayiou-Thomas, Lisa Henderson, Sophie Brigstocke and Emma Truelove. We also thank several graduate students who helped us to identify glossary terms: Nabilah Halah, Anna Jordan, Maria Markogiannaki, Silvana Mengoni, Zoi Pappa, Noah Wang. Our thanks also go to Susannah Witts and Geraldine Collins for administrative support and Peter Bailey, Kim Manderson, John Hobcraft, Anne Hillairet de Boisferon and Cathy Price for assistance at various stages. Several chapters of the book were written while MJS was in receipt of a British Academy Research Readership. We also acknowledge the support of the British Academy, ESRC, Nuffield Foundation, The Health Foundation and the Wellcome Trust for supporting our research at various stages in the book’s preparation. Finally, Gerry Tehan and Bill Lovegrove kindly hosted our study visit to the University of Southern Queensland in 2006 which was very helpful to us while writing this book. Our thanks to all these people for their help, support and friendship.

Every effort has been made to trace copyright holders and to obtain their permission for the use of copyright material. The publisher apologizes for any errors or omissions in the above list and would be grateful if notified of any corrections that should be incorporated in future reprints or editions of this book.

1

Understanding Developmental Cognitive Disorders

John, Peter, and Ann are three 7-year-old children. John’s parents and teachers have concerns about his progress in learning to read. John is generally bright and understands concepts well. Formal testing showed that he had a high IQ (120) with somewhat higher scores on the performance than the verbal scales of the test. John could only read a few simple words on a single word-reading test – a level of performance equivalent to a typical 5½-year-old child. John does not know the names or sounds of several letters of the alphabet. Verbally John is a good communicator, though he does show occasional word-finding problems and occasionally mispronounces long words. John is a child with dyslexia.

Peter is also a bright little boy (IQ 110, but with markedly lower scores on the performance than the verbal subtests). He has made a very good start with learning to read, and on the same test given to Peter he read as many words correctly as an average 8-year-old child. Peter has severe problems with games and sport at school, particularly with ball games. He is notably ill-coordinated and frequently drops and spills things. He has very serious difficulties with drawing and copying, and his handwriting is poorly formed and difficult to read. Peter has developmental coordination disorder.

Ann is a socially withdrawn child. She avoids interacting with other children in school whenever she can. She is sometimes observed rocking repetitively and staring out of the classroom window. Ann’s communication skills are very poor, and she appears to have quite marked difficulties understanding what is said to her, particularly if what is said is at all abstract. When an attempt was made to give Ann a formal IQ test, testing was discontinued because she refused to cooperate. The few items she did complete suggested she would obtain a very low IQ score. Ann is fascinated by cars and will spend many hours cutting out pictures of them to add to her collection. Ann is a child with autism.

These three cases of 7-year-old children illustrate some of the varied cognitive problems that can be observed in children. In this book we will attempt to provide a broad survey of the major forms of cognitive disorder found in children, and lay out a theoretical framework for how these disorders can best be understood. Understanding these disorders, in turn, holds prospects for how best to treat them. Our approach to these disorders is from a developmental perspective, by which we mean that a satisfactory understanding of these disorders needs to be informed by knowledge of how these skills typically develop. Most of the explanations we consider in the book will focus on the cognitive level: a functional level dealing with how the brain typically learns and performs the skills in question. Wherever possible, however, we will relate these cognitive explanations to what is known about the biological (genetic and neural) mechanisms involved in development. The interplay between genetic, neural, and cognitive explanations for behavioral development is currently an area of intense activity and excitement.

Some Terminology for Classifying Cognitive Disorders

In this book we will consider a wide range of developmental disorders that affect language, learning, and cognition. The disorders considered include those affecting language, reading, arithmetic, motor skills, attention, and social interaction (autism spectrum disorders). There are a number of features that are shared by the disorders we will discuss: they all occur quite commonly and have serious consequences for education, and thereafter for well-being in adulthood. There is also good evidence that all these disorders reflect the effects of genetic and environmental influences on the developing brain and mind.

To begin with it is important to distinguish between specific (or restricted) difficulties and general difficulties. Specific difficulties involve disorders where there is a deficit in just one or a small number of skills, with typical functioning in other areas. General difficulties involve impairments in most, if not all, cognitive functions. Terminology in this field differs between the UK and the USA; we will consider both here, but we will use primarily British terminology in later sections of the book.

In the UK a selective difficulty in acquiring a skill is referred to as a “specific learning difficulty.” The term learning difficulty makes it clear that skills must be learned; specific means that the difficulty occurs in a restricted domain. Dyslexia is one of the best known and best understood examples of a specific learning difficulty. Children with dyslexia have specific difficulties in learning to read and to spell, but they have no particular difficulty in understanding concepts and may have talents in many other areas such as science, sport, and art. In the USA (following DSM-IV, the of the American Psychiatric Association) such specific difficulties are called learning disorders.