Book Review: Diagnostic Dilemmas in Developmental Disabilities: Fuzzy Margins at the Edges of Normality. An Essay Prompted by Thomas Sowell's New Book: The Einstein Syndrome

Sowell's “Einstein children” are rare, extraordinarily gifted children, often the offspring of engineers or other highly educated musical families, in whom exceptional visual/spatial reasoning skills mature much earlier than language skills. Sowell states that speechless children with demonstrably superior nonverbal problem-solving skills and mathematical ability whose language comprehension is adequate have a favorable outlook with or without intervention, even if their social skills and behavior are suboptimal. He stresses that listening to parents' reports of their children's accomplishments at home provides more reliable information than questionnaires or formal one-time evaluations to distinguish between inability and unwillingness to speak or perform. He strongly objects to invasive and stressful tests for such children and questions the effectiveness of the many early interventions offered to children with developmental disorders. Certainly, providing a definite prognosis in very young children is hazardous because it is so subject to error, unless there is independent evidence for a serious neurologic problem with brain dysfunction or incontrovertible signs of truly exceptional cognitive ability. Early, individualized intervention is mandatory for children, no matter how bright, whose language comprehension is inadequate, and for those with troublesome behavioral traits bordering on or indicative of an autistic spectrum (pervasive developmental disorder/PDD) diagnosis. Children with isolated abilities who are functionally inept in every day life are not “Einstein children” and their deficits must be addressed promptly and specifically. Sowell's book raises important issues about behaviorally based diagnoses. Developmental disorders are not diseases that one does or does not have but are behaviorally defined dimensional traits along a continuum with fuzzy edges and a wide range of severity. Therefore, there is no crisp partition between normalcy and disorder, and between disorders with different names yet shared features, even when there is no controversy regarding the identification of prototypic exemplars. The utility for practical and research reasons of agreed upon standard diagnostic criteria is not in question, provided the statistical rather than biological nature of the criteria is kept in mind. Most subtypes of disorders like autism, dyslexia, or attention deficit are defined by arbitrary cuts in a bell-shaped spectrum of disability, which in no way invalidates their organic, neurologic basis. Developmental disorders are rarely the consequences of single gene defects or of definable postnatal insults; they have many causes that vary among individuals. Like many complex human traits, they are the expression of extremely complex multigenic influences on brain development. Because single gene defects are rare causes of these disorders, medical testing needs to be constrained by the history and examination. Intervention must address each child's particular needs and is, for the most part, educational.