When psychopathology is defined as developmental deviation, its study necessarily involves a wedding of research on the normal and the pathological. In such an endeavor, understanding of normal processes is enhanced, because critical normative issues can only be defined in terms of their implications when development goes awry and because disordered behavior often brings into sharp relief the nature of basic developmental phenomena. At the same time, such work is critical to defining general principles of development, which apply to normal and abnormal alike. In this article, examples are provided of the reciprocally enhancing nature of studies of normal and pathological development and of the fruitfulness of weaving back and forth between studies of normality and disturbance for understanding important aspects of development. Examples include a discussion of attachment and dependency and the origins of Attention Deficit/Hyperactivity Disorder. It is concluded that developmental psychopathology may make its greatest contribution in the endeavor to understand development of individuals.

Research in developmental psychopathology is used to examine and propose questions, concepts, and methods in the investigation of child development in the contexts of dysfunctional and well families. The adequacy of the data base for investigating the course of development, representing the socialization process, and identifying individualities and universals in development is discussed. A number of research issues that have been studied primarily in developmental psychopathology are recommended as relevant to normal child development. Multidomain and multisource longitudinal data are proposed as the means for better delineating development and for testing alternative models of developmental processes. Examples of data and experience are drawn from longitudinal studies of affectively ill parents and their children. Differences in the perspectives and approaches of normal child development research and developmental child psychopathology are discussed. The usefulness of thinking of two disciplines, normal child development and child development psychopathology, is questioned.

The study of clearly identifiable patterns of atypical development can inform normal development in significant ways. Delayed or deviant development puts in high relief not only the sequence of development but also the individual components. This article presents the results of studies that compare adolescents with Williams syndrome, a rare metabolic neurodevelopmental disorder resulting in mental retardation, with cognitively matched adolescents with Down syndrome. We investigate the interaction between affect and language through storytelling. In contrast to the adolescents with Down syndrome, the Williams syndrome subjects tell coherent and complex narratives that make extensive use of affective prosody. Furthermore, stories from the Williams but not the Down subjects are infused with lexically encoded narrative evaluative devices that enrich the referential content of the stories. This contrast in expressivity between two matched atypical groups provides an unusual perspective on the underlying structure of the social cognitive domain.

This article reviews ways in which quantitative genetic approaches to developmental psychopathology can elucidate normal development. A few examples from genetics are discussed to highlight how investigations of abnormal functioning can inform the study of normal functioning. Two topics that provide bridges between the normal and abnormal are presented in greater detail. Most important is a new quantitative genetic technique that assesses empirically genetic and environmental links between the normal and abnormal. A second topic involves quantitative genetic approaches to environmental analyses, as highlighted by the examination of nonshared environmental factors. Such examinations of the environment are essential in studies of psychopathology, and their application to abnormal development can elucidate processes of normal development. We believe that forging links between the normal and abnormal is the core task of developmental psychopathology and that quantitative genetics is not only compatible with this goal, but essential to it.

Schizophrenia is being increasingly viewed as a neurodevelopmental disorder, that is, one in which early, fixed pathology becomes manifest clinically during the normal course of maturation of the brain. Evidence for this position comes first from neuroimaging research, such as (1) studies that demonstrate morphologic brain changes (such as ventriculomegaly on CT scans) even in first break patients; and (2) a lack of correlation between these morphologic changes and duration of illness. Another source of evidence is studies of normal brain development in rodents and primates, including research that shows (1) the prefrontal cortex is a late maturing part of the brain, and (2) lesions of the prefrontal cortex may be initially silent and show delayed onset of dysfunction as the brain matures. A neurodevelopmental approach to schizophrenia, in turn, has stimulated further work into the normal development of brain regions implicated in the illness, such as the frontal cortex. Thus, the fields of neuropsychiatry and neurodevelopment have been mutually stimulated during the course of this work. In addition, viewing schizophrenia in developmental terms may have implications for the understanding of changes in cognition and behavior during normal adolescence.

This article reviews the research on resilience in order to delineate its significance and potential for understanding normal development. Resilience refers to the process of, capacity for, or outcome of successful adaptation despite challenging or threatening circumstances. Three resilience phenomena are reviewed: (a) good outcomes in high-risk children, (b) sustained competence in children under stress, and (c) recovery from trauma. It is concluded that human psychological development is highly buffered and that long-lasting consequences of adversity usually are associated with either organic damage or severe interference in the normative protective processes embedded in the caregiving system. Children who experience chronic adversity fare better or recover more successfully when they have a positive relationship with a competent adult, they are good learners and problem-solvers, they are engaging to other people, and they have areas of competence and perceived efficacy valued by self or society. Future studies of resilience will need to focus on processes that facilitate adaptation. Such studies have the potential to illuminate the range and self-righting properties of, constraints on, and linkages among different aspects of cognitive, emotional, and social development.