The data for 197 mother–infant pairs from two longitudinal studies were analyzed to assess relations between maternal attachment representations; atypical maternal behavior, coded with a new tool, Atypical Maternal Behavior Instrument for Assessment and Classification (AMBIANCE), and infant attachment. Both maternal and infant attachment were systematically related to atypical maternal behavior: mothers who were Unresolved on the Adult Attachment Interview and those whose infants were disorganized in the Strange Situation Procedure engaged in more atypical behaviors than those who were not Unresolved and whose infants showed organized patterns of attachment, respectively. Regression analyses indicated that when tested as a mediator, atypical maternal behavior as measured on the AMBIANCE did not reduce the association between maternal Unresolved status and infant disorganized attachment. This may, in part, reflect the fact that our low-risk sample did not include enough cases in the risk categories. These data provide preliminary empirical validation for the AMBIANCE and strengthen the evidence for links between atypical maternal behavior and disorganized attachment but indicate that in addition to maternal attachment representations, other factors must contribute to atypical maternal behavior.

With the passing of Paul E. Meehl, Regents Professor of Psychology at the University of Minnesota, on February 14, 2003, the world lost one of the most influential clinical psychologists of the 20th century. The breadth of his interests, the preciseness and clarity of his thinking, the elegance of his writing, and his ability to integrate scientific and clinical matters of import were hallmarks of his illustrious career (see, e.g., Meehl, 1954, 1973, 1991). Yet, it is the very magnitude of his professional pursuits that defy categorization or even placement within a single field of inquiry. Whether they pertain to philosophical matters, measurement and psychodiagnostic issues, or elucidating psychopathological processes, Paul Meehl's contributions were seminal and established a base on which scholars could build their own theoretical and research perspectives. Although Paul certainly did not consider himself to be a developmental psychopathologist, his influence can be seen in the theoretical and methodological streams that have nurtured the emergence and growth of the field. Thus, it seems a fitting tribute to Paul that this Special Issue, “Conceptual, Methodological, and Statistical Issues in Developmental Psychopathology,” be dedicated in his honor.

One of the distinguishing principles that has guided research conducted within a developmental psychopathology perspective is that knowledge of normal development is necessary to comprehend psychopathology and that, conversely, the examination of maladaptive and psychopathological development can elucidate the normal functioning of individuals (Cicchetti, 1984, 1990a, 1990b, 1993; Rutter, 1986; Sroufe, 1990; Werner, 1948). Because all pathology can be conceived as a disturbance, distortion, or degeneration of normal functioning, in order to understand psychopathology it is essential that the normal functioning with which psychopathology is compared be fully grasped (Cicchetti, 1984, 1990a; Kaplan, 1967; Rutter & Garmezy, 1983). Likewise, understanding how mental disorders evolve and how aberrations in the organization of component developmental systems that exist among disturbed individuals eventuate may be informative for elucidating critical components of normal development.

Mutual regulation of anger plays a role in both healthy adjustment and mental health problems. This study of 85 preschooler boys and girls examined mother–preschooler anger regulation during a frustration in relation to the child's preschool and school age problem status. Less mutual positive emotion, more mutual anger, and more emotional mismatches than other dyads characterized dyads with a stable conduct problem child. Maternal emotion predicted school age conduct problems, particularly for boys. Maternal emotion also predicted stability versus improvement of symptoms. The emotional dynamics of mother–preschooler angry exchanges may redirect girls' conduct problems and may contribute to the stability of boys' conduct problems.

Questions concerning the long-term effects of early experience on psychological development in humans continue to stir up controversy. There are, at present, great diversity and contradictions among extant conceptual models and inadequate data to resolve these differences. Limited opportunities to use experimental approaches and the inherent restrictions of observational approaches in research on humans implies that alternative research designs are needed. This article examines the use of “natural experiments” as a method for testing hypotheses concerning the effects of early experience on psychological development. The benefits and limitations of using natural experiments are reviewed and several case illustrations are considered.

There is little documentation of how and when joint attention emerges in blind infants because the study of this ability has been predominantly reliant on visual information. Ecological self-knowledge, which is necessary for joint attention, is impaired in blind infants and is evidenced by their reaching for objects on external cues, which also marks the beginning of their Stage 4 understanding of space and object. Entry into Stage 4 should occur before joint attention emerges in these infants. In a case study of two totally blind infants, the development of joint attention was longitudinally examined during Stage 4 in monthly sessions involving interactions with objects and familiar adults. The interactions were scored for behavior preliminary to joint attention, behavior liberally construed as joint attention, and behavior conservatively construed as joint attention. Behavior preliminary to joint attention occurred throughout Stage 4; behavior suggestive of joint attention by both liberal and conservative standards emerged initially in Stage 4 and became prevalent by mid to late Stage 4. The findings are discussed in terms of how they inform our thinking about the development of joint attention with respect to the importance of vision, cognition, social context, language, and early self-knowledge.

Child–parent attachment quality with an adoptive caregiver at age 4 years was examined in a sample of 111 children adopted into the United Kingdom following early severe deprivation in Romania and a comparison group of 52 nondeprived within–United Kingdom adoptees. Findings indicated that, compared with nondeprived adoptees, children who experienced early severe deprivation were less likely to be securely attached and more likely to show atypical patterns of attachment behavior; ordinary forms of insecure attachment were not associated with deprivation. Within the sample of deprived adoptees, there was a dose–response association between duration of deprivation and disturbances in attachment behavior. In addition, a minority of children who experienced severe early deprivation were classified as avoidant, secure, or dependent using conventional classification strategies, despite also exhibiting atypical patterns of attachment behaviors, and this was also more likely among children exposed to prolonged deprivation. The results raise both theoretical and methodological implications for attachment research on very deprived children.

Developmental psychopathologists have criticized categorical classification systems for their inability to account for within-group heterogeneity in biological, etiological, developmental, and cultural influences on behavior. Dichotomizing continuous scores of symptom severity is also inadvisable statistically. Perhaps because of a resulting wariness of categorizing, few explorations into the ontological status of traits or disorders as dimensional versus discrete have been conducted. It is argued here that the limitations of categorizing have little to do with the ontological status of traits and that developmental psychopathologists should be concerned with identifying discrete behavioral syndromes. Common taxometric methods for resolving discrete traits are described, and questions of concern to developmental psychopathologists are outlined that can be addressed through taxometrics studies. These include (a) identifying children who are at risk for future psychopathology, (b) identifying discrete subtypes within current diagnostic classes, (c) locating sensitive periods in the development of discrete pathological traits, (d) discovering moderators of treatment outcome, and (e) elucidating mechanisms of equifinality and multifinality. Although most behavioral traits probably are distributed continuously, identifying those that are discrete will advance the science of developmental psychopathology. Disorders for which taxometric analyses might be applied include anxiety, attention deficit hyperactivity disorder, autism spectrum disorders, conduct problems, depression, and schizophrenia.

The question of whether to view psychopathology as categorical or dimensional continues to provoke debate. We review the many facets of this argument. These include the pragmatics of measurement; the needs of clinical practice; our ability to distinguish categories from dimensions empirically; methods of analysis appropriate to each and how they relate; and the potential theoretical biases associated with each approach. We conclude that much of the debate is misconceived in that we do not observe pathology directly; rather, we observe its properties. The same pathology can have some properties that are most easily understood using a dimensional conceptualization while at the same time having other properties that are best understood categorically. We suggest replacing Meehl's analogy involving qualitatively distinct species with an alternative analogy with the “duality” of light, a phenomenon with both wave- and particle-like properties.

During the past 10 years researchers studying children adopted from Romanian orphanages have had the opportunity to revisit developmental questions regarding the impact of early deprivation on child development. In the present paper the effects of deprivation are examined by reviewing both the early and more recent literature on studies of children who spent the first few years of life in institutions. Special attention is given to the Canadian study of Romanian adoptees in which the author has been involved. Findings across time and studies are consistent in showing the negative impact of institutionalization on all aspects of children's development (intellectual, physical, behavioral, and social–emotional). Results of studies show, however, that institutionalization, although a risk factor for less optimal development, does not doom a child to psychopathology. However, the impact of institutionalization is greater when coupled with risk factors in the postinstitutional environment. Methodological and conceptual difficulties in research with institutionalized samples of children are discussed and future directions for research are considered.

This study examined the association between maternal cocaine use and children's emotional regulation. Using a brief separation procedure, we observed 78 18-month-old at-risk children and their mothers from three defined maternal groups: no drug use; no cocaine use but a positive history for alcohol, tobacco, and/or marijuana; and cocaine use with or without alcohol, tobacco, and/or marijuana. Coded videotaped behavior identified three maternal constructs (separation style, physical engagement, and emotional engagement) and three child constructs (negative reactivity to separation, initial regulatory activity, and follow-up positive emotional engagement). Cocaine-using mothers displayed less emotional engagement than other mothers. Children with cocaine-using mothers displayed less negative reactivity and follow-up positive emotional engagement than their counterparts. Child reactivity was connected to maternal drug use, whereas emotional engagement during reunion was linked to birthweight and maternal behavior. Results suggest a possible impairment or restriction of emotional expression and regulation in the face of stress and/or maternal disengagement that is more common among cocaine-exposed children with their mothers.

The nature of mother–child interaction in autism and the maternal approach characteristics that elicit social response in children with autism were examined in two studies. Mother–child play sessions of 24 preschool children with autism and 24 typically developing preschoolers were compared in Study 1, and play sessions of 9 mothers with their autistic child and with their nonautistic child were compared in Study 2. Mother–child interactions were coded using the Approach Withdrawal Interaction Coding System to quantify maternal approach behaviors and child responses. Results of Study 1 indicate that, although the quantity of approaches did not differ between mothers with their autistic children and mothers with their nonautistic children, there were qualitative differences. Mothers used more physical contact, more high-intensity behaviors, and fewer social verbal approaches with autistic children. Results of Study 2 replicated these findings with mothers showing a similar pattern of approach toward their autistic children but not their nonautistic children. Although autistic children displayed lower contingency to maternal approaches in general, they showed greater responsiveness to approaches involving increased physical proximity and/or containing nonverbal object use. Mothers socially engaged both autistic and nonautistic children. The implications for parent training and intervention are discussed.

Ninety-nine 2-year-olds, out of a larger sample of 474 children, were classified as high (n = 49) or low (n = 50) in externalizing (aggressive/destructive) behaviors based on maternal reports assessed twice across a 2-month period. During a laboratory assessment, these toddlers participated in two empathy-eliciting tasks, from which affective, behavioral, and physiological measures were derived. Relations among measures of empathy were examined both within and across episodes and aggression groups. Analyses indicated that different indices of empathy were related to each other, both within and across empathy situations. In addition, aggressive children displayed more behaviors indicative of empathy than did nonaggressive children. Finally, a pattern of physiological responding to another's distress was evident across both groups of children, and some results indicated that greater physiological regulation was related to less empathy-related behavior. Results are discussed in terms of the developing nature of empathy and its changing association with both self-regulation and aggression.

This article deals with alternative research strategies for developmental psychopathology. It argues that most applications of statistical methods in empirical research are variable centered, not person oriented. As a result, conclusions are often drawn that fail to do justice to the diverse nature of populations. It is recommended that we take seriously the importance of the implications of data aggregation. The difficulties of making inferences from a more aggregated level of analysis to a less aggregated level are explained and exemplified. We explain that a set of variables displays dimensional identity if the variable relationships remain unchanged across the levels or categories of other variables. Data examples of intelligence divergence and of Child Behavior Checklist subpopulation differences show that lack of dimensional identity can lead to incorrect conclusions. Schmitz' theorems on aggregation and the validity of results at the aggregate level for individuals are illustrated using data from a study on the development of alcoholism and discussed from a person-oriented perspective. Statistical methods suitable for person-oriented data analysis are reviewed.

This paper provides an overview of the largest longitudinal investigation of institutionalized children less than 2 years old ever conducted. The Bucharest Early Intervention Project is an ongoing randomized controlled trial of foster placement as an alternative to institutionalization in abandoned infants and toddlers being conducted in Bucharest, Romania. In addition to describing the contexts in which this study is imbedded, we also provide an overview of the sample, the measures, and the intervention. We hope that the natural experiment of institutionalization will allow us to examine directly the effects of intervention on early deprivation. We hope it will provide answers to many of the critical questions that developmentalists have asked about the effects of early experience, the timing of deprivation, and the ameliorating effects of early intervention and provide clues to which underlying neurobiological processes are compromised by, and resilient to, dramatic changes in early experience.

Research suggests that exposure to extreme stress in childhood, such as domestic violence, affects children's neurocognitive development, leading to lower intelligence. But studies have been unable to account for genetic influences that might confound the association between domestic violence and lower intelligence. This twin study tested whether domestic violence had environmentally mediated effects on young children's intelligence. Children's IQs were assessed for a population sample of 1116 monozygotic and dizygotic 5-year-old twin pairs in England. Mothers reported their experience of domestic violence in the previous 5 years. Ordinary least squares regression showed that domestic violence was uniquely associated with IQ suppression in a dose–response relationship. Children exposed to high levels of domestic violence had IQs that were, on average, 8 points lower than unexposed children. Structural equation models showed that adult domestic violence accounted for 4% of the variation, on average, in child IQ, independent of latent genetic influences. The findings are consistent with animal experiments and human correlational studies documenting the harmful effects of extreme stress on brain development. Programs that successfully reduce domestic violence should also have beneficial effects on children's cognitive development.

This study evaluated the role of attentional shifting in children's prosocial behavior with peers. Participants were 27 aggressive/rejected and 27 nonaggressive/popular kindergarten and first grade boys and girls. Children's ability to shift attention from one affective state to another was assessed during: (a) a computerized task that required shifting attention between different affective events (i.e., the Children's Attentional Shifting Task, CAST) and (b) an analogue entry task with unacquainted peers. Children's latency for sharing with peers was assessed after they experienced failure during the entry task. Aggressive/rejected children had significant difficulty shifting attention from negative to positive affect during the CAST and were slower to share after experiencing entry failure. In general, aggressive/rejected children were less able to regulate their behavior effectively after experiencing social failure. Girls, regardless of status, had less difficulty than boys shifting attention from one affective state to another during the CAST. In addition, children's social status/aggressiveness, their ability to regulate emotional behavior after social failure and to shift attention effectively on the CAST predicted approximately 31% of the variance in their latency to share. These findings suggest that the ability to shift attention between different affective states plays a significant role in children's prosocial behavior with peers.

The field of developmental psychopathology is faced with a dual challenge. On the one hand, we must build interdisciplinary theoretical models that adequately reflect the complexity of normal and abnormal human development over time. On the other hand, to remain a viable empirical science, we must rigorously evaluate these theories using statistical methods that fully capture this complexity. The degree to which our statistical models fail to correspond to our theoretical models undermines our ability to validly test developmental theory. The broad class of random coefficient trajectory (or growth curve) models allow us to test our theories in ways not previously possible. Despite these advantages, there remain certain limits with regard to the types of questions these models can currently evaluate. We explore these issues through the pursuit of three goals. First, we provide an overview of a variety of trajectory models that can be used for rigorously testing many hypotheses in developmental psychopathology. Second, we highlight what types of research questions are well tested using these methods and what types of questions currently are not. Third, we describe areas for future statistical development and encourage the ongoing interchange between developmental theory and quantitative methodology.

Adoption provides a unique opportunity for the study of child development. Because adopted children are raised in families in which they have no genetic relationship with their parents, and possibly none with their siblings, they provide a rare opportunity to study the relative importance of genetic, shared environmental, and nonshared environmental influences on the development of child characteristics and behaviors. Because children are adopted from a variety of circumstances and at a wide range of ages, studies of adopted children and their families provide researchers the opportunity to examine the short- and long-term influences of a wide range of environments on children's development. Because children are adopted into homes with a range of characteristics (e.g., multiracial homes), adoption provides the opportunity to study the range of influences of these homes on child development. Adoption research that focuses on each of these areas is reviewed in this article. We present conclusions about the value of adoption in psychological research and some reasons why many psychologists ignore the opportunities presented by studying adoptive families, as well as potential useful directions for future research with adopted children and their families.

The assertive speech acts of children with autism (n = 12) and Asperger syndrome (n = 12), individually matched to children with specific language impairment (SLI; n = 24) and children with normal development (n = 24) were studied in the context of gently structured conversation. These children also completed the false belief test of theory of mind. The children with autism used significantly lower proportions of assertions involving explanations and descriptions than the children with SLI or normal development and significantly lower proportions of assertions involving internal state and explanations than the children with Asperger syndrome. The children with autism used a higher proportion of assertions involving identifications than any other group. The assertions of the children with Asperger syndrome were generally not different than those of the children with SLI or normal development except for a higher proportion of assertions involving own internal state. Further analysis of the mental assertions revealed that the children with autism and Asperger syndrome predominantly referred to desire and made few references to thought and belief, whereas the children with SLI and those with normal development used a higher proportion of references to thought and belief.