A Neurodevelopmental Approach to Specific Learning Disorders: Clinics in Developmental Medicine 145

Is there any reason to believe that reading, writing, and arithmetic involve different mechanisms of the brain? Do hearing, understanding, and expressing rely on separate brain mechanisms? These are some of the questions of interest to anyone concerned with how the brain functions that are discussed in this multiauthored book. The obvious targets for this work are child psychiatrists, psychologists, and educators. Philosophers of the mind, those interested in the question of what makes us human, will also find this book of great value. Why would general psychiatrists be interested in a book on learning disorders? Certainly, this is an area of interest to researchers, but I would argue that in addition to the obvious practical problems to be solved, there are heuristic reasons to study these problems. The confusion of DSM-IV, ICD-10, and the common parlance among “mental retardation,” “pervasive developmental disorders,” and the “disorders of psychological development” only mirror the confusion regarding mental function in general. This results in conflicts based on ideological and dogmatic approaches to mental functioning.

This excellent book introduces clarity to the question based on an understanding of the historical background of different professional approaches to learning problems. The question of specific brain areas for specific brain functions is addressed, as are the relative contributions of social and economic deprivation, organic deficits of central nervous system organization, and the effects of acquired brain damage.

The goal of such knowledge is, of course, prevention and, secondarily, treatment. A correct diagnosis or evaluation of the problem is a prerequisite for effective treatment, whether it be behavioral, educational, pharmacological, or combinations thereof.

The title, A Neurodevelopmental Approach to Specific Learning Disorders, in a way summarizes the evolution of thinking about mental processes that has resulted from the application of the scientific method to neurophysiology and the parallel growth of the science of psychology. There remains, however, a gap between what has been learned about human behavior by the modern science of neuropsychiatry and its application to public policy, both in the education of our children and in the correction of the antisocial and violent among us. The term “neurodevelopmental” suggests that during the growth of an organism something has gone wrong in the maturation of the brain, and “specific” implies that various functions of the brain are independent from each other. Both interpretations are partially true and partially false.

If brain disorders are genetic, then it is not the construction of the brain that is amiss but the blueprint. If the blueprint is correct and the development goes bad, then there must be some intrinsic or extrinsic factor that results in the failure to achieve the inborn genetic potential. As usual, Freud framed the question in a way that sounds surprisingly modern.

The nature versus nurture question has engaged students of human biology since the time of the ancient Greeks, but nowhere has the argument been more contentious than in the study of human intelligence and the ability to learn. The defining dilemma of the science of mind is the question of language. It is the power of speech that separates man from the other animals and inner speech that defines our intellect. That is not to say that nonverbal intelligence and our unspoken emotional life is not important, but it is speech that makes humankind unique. Books such as Pinker’s How the Mind Works(2) and Damasio’s The Feeling of What Happens(3) bring to the sophisticated layman the neurology of human thought in bestseller format. If the proper study of man is man, then the neurobiology of the self is what psychiatry is about. Philosophers and their modern descendants, neuroscientists, have contemplated speech, language, and the deficits thereof as means to study and understand the greater question of consciousness or, if you will, self-consciousness. It was appreciated very early on in human history that language was the result of a developmental process. Speech does not spring full-blown, nor does useful vision, ambulation, or even bladder control.

It was in the year 397 A.D. that St. Augustine analyzed autobiographically the process of an infant learning to speak:

This same argument, essentially, was outlined by Richard Allen Chase at a National Institutes of Health conference in 1965 (5) and by Noam Chomsky with the publication of Language and Mind in 1968 (6). The philosophy of mind and behavioral sciences had converged in a theoretical model that, however, lacked an empirical and neuroanatomical base.

A Neurodevelopmental Approach to Specific Learning Disorders is a useful book on many levels. The chapter on the neurological basis of learning disorders in children by Jay Keith Brown and Robert A. Minns could by itself be worth the price of the book. This lucid and current review of the brain as the organ of learning summarizes our current knowledge of functional brain anatomy from DNA, through cells and synapse, to hemispheric dominance. Various types of learning, from reflex behavior through preprogrammed or conditioned behaviors to true learned behavior, including motor learning, emotional learning, and cognitive learning, are explained. With that background, dyslexia, dysgraphia, and dyscalculia are discussed in detail. The question of whether these conditions represent “developmental lags,” “minimal brain dysfunction,” or subsets of “attention deficit disorder” is not just semantic.

The overlaps and distinctions between behavioral and learning disorders and what the Scandinavian literature refers to as DAMP (deficits in attention, motor control, and perception) emphasize the fact that most children diagnosed as hyperactive are probably not truly so. The term “attention deficit disorder” is a tautology because it must be either attention deficit or attention disorder, not both. This book contains a great deal of epidemiological, statistical, and longitudinal data to support this argument.

Each chapter develops from a historical perspective but is eminently useful clinically. They deal with prenatal and perinatal risk factors, psychological factors, and the role of the family interaction. The comorbidity and the links with other behavioral problems are emphasized in the chapter by Thomas G. O’Connor and Robert Z. Pianta. This includes the pearl that 36% of children with behavioral problems have reading problems and 69% of children with reading problems have behavioral problems, and that the long-term effects of learning problems are most serious in the lower socioeconomic groups.

A practical guide to neurodevelopmental assessment is presented with specific guidelines for the evaluation of children with school and behavior problems. This very practical examination is used by school doctors and pediatricians in Belgium. It has been carefully evaluated in a follow-up study showing that when given to children in kindergarten, it correctly classified 80% of the children who manifested a specific learning disorder by third grade. Since this examination requires only 30 minutes, it should be part of every pediatrician’s armamentarium.

The chapter on brain imaging in learning disorders is particularly useful in that it pulls together current practice and research on single photon emission computed tomography, magnetic resonance imaging (MRI), and EEG. I am in full agreement with the summary statement by Peter Born and Hans C. Lou: “We think that all patients presenting with learning disorders serious enough to disrupt everyday functioning should be referred for a cerebral structural MRI examination, particularly if the history or general physical examination gives clues to generalized or localized neurological conditions” (p. 256). The learning disorders are not simply the result of generalized developmental disability or sensory impairment.

There are practical chapters on managing specific learning difficulties in the classroom, directions to take for primary and secondary prevention in the future, and what psychotherapeutic or pharmacological interventions are useful. Treatment of concomitant behavioral problems and use of stimulants, antidepressants, anticonvulsants, and other drugs, as well as diet, alternative treatments, and psychoeducational interventions, behavioral modification programs, and programmatic modifications, are all elucidated. The Textbook of Pediatric Neuropsychiatry(7) summarizes language disorders in 27 pages, but it lacks the practical advice and guidelines presented in this book.

It is difficult in a book review to convey without a number of specific quotes the precision of language, the clarity of presentation, and the logical organization of this multiauthored book. The contributors represent an international spectrum of ideas, and the editors must be congratulated for bringing together pediatricians, neuroscientists, neurologists, psychiatrists, psychologists, occupational therapists, and educators to produce a book with so little overlap and so few wasted words. Learning and associated behavior disorders receive little attention in the education of most psychiatrists because they are not amenable to treatment with psychoanalytically oriented psychotherapy, but methods exist to manage them.

A Neurodevelopmental Approach to Specific Learning Disorders is recommended for all child and adolescent psychiatrists, but it also should be part of the background knowledge of everyone practicing psychiatry or psychology. This body of knowledge needs to be in the hands of schoolteachers and school psychologists and those who shape the public policy responsible for the school guidance system and curriculum development. The shelf labeled “Linguistic”s in a local bookstore that I visited contained more than 100 volumes. Of those, I would recommend this one.