The term plasticity is often confined to changes due to learning. We believe, however, that the rapid lability of human behavior as different mental contents receive attention represents an important form of plasticity. Recent research in temperament and cognitive neuroscience provides an account of the development of a specific neural system involved in attentional self-regulation. In this paper, we concentrate on a network involved in orienting. We describe what is currently known about this network and its development during the first years of life. This network interacts with other attentional networks that come to control orienting to remembered events as well as those currently present. Orienting reflects processes that are both deeply biological and also open to cultural influences through learning. Attention is influenced by the current emotional state and is also important in achieving control over the emotional state. We present evidence on how learning influences eye position between 4 and 18 months of life and indicate influences of orienting on important aspects of infant behavior. Like any biological system, problems can arise in these mechanisms. We speculate on how individual differences in distress proneness and orienting may relate to the development of psychopathology.

We examined the influence of a common allelic variation in the dopamine receptor D4 (DRD4) gene and caregiver quality on temperament in early childhood. Children 18–21 months of age were genotyped for the DRD4 48 base pair tandem repeat polymorphism, which has been implicated in the development of attention, sensation seeking, and attention-deficit/hyperactivity disorder. The children also interacted with their caregiver for 10 min in a laboratory setting, and these videotaped interactions were coded for parenting quality using an observational rating procedure. The presence of the DRD4 7-repeat allele was associated with differences in the influence of parenting on a measure of temperamental sensation seeking constructed from caregiver reports on children's activity level, impulsivity, and high-intensity pleasure. Children with the 7-repeat allele were influenced by parenting quality, with lower quality parenting associated with higher levels of sensation seeking; children without the 7-repeat allele were uninfluenced by parenting quality. Differences between alleles were not related to the child's self-regulation as assessed by the effortful control measure. Previous studies have indicated that the 7-repeat allele is under positive selective pressure, and our results are consistent with the hypothesis that the DRD4 7-repeat allele increased children's sensitivity to environmental factors such as parenting. This study shows that genes influence the relation between parenting and temperament in ways that are important to normal development and psychopathology.

Human variability in temperament allows a unique natural experiment where reactivity, self-regulation, and experience combine in complex ways to produce an individual personality. Personality disorders may result from changes in the way past memories filter new information in situations of emotional involvement with others. According to this view, disorders are specific to their initiating circumstances rather than a general difficulty that might extend to classes of information processing remote from triggers for the disorder. A different view suggests a more general deficit in attentional control mechanisms that might extend to a wide range of situations far from those related to the core abnormality. This paper outlines methods for examining these views and presents data from the study of borderline personality disorder, arguing in favor of high negative emotionality being combined with a deficit in an executive attentional control network. Because this attentional network has already been well described in terms of anatomy, the cognitive operations involved, development, chemical modulators, and effects of lesions and candidate genes, these findings may have implications for understanding the disorder and its treatment. We consider these implications in terms of a general approach to the study of personality development and its disorders.

Child development involves both reactive and self-regulatory mechanisms that children develop in conjunction with social norms. A half-century of research has uncovered aspects of the physical basis of attentional networks that produce regulation, and has given us some knowledge of how the social environment may alter them. In this paper, we discuss six forms of developmental plasticity related to aspects of attention. We then focus on effortful or executive aspects of attention, reviewing research on temperamental individual differences and important pathways to normal and pathological development. Pathologies of development may arise when regulatory and reactive systems fail to reach the balance that allows for both self-expression and socially acceptable behavior. It remains a challenge for our society during the next millennium to obtain the information necessary to design systems that allow a successful balance to be realized by the largest possible number of children.

Self-organization can be approached in terms of developmental processes occurring within and between component systems of temperament. Within-system organization involves progressive shaping of cortical representations by subcortical motivational systems. As cortical representations develop, they feed back to provide motivational systems with enhanced detection and guidance capabilities. These reciprocal influences may amplify the underlying motivational functions and promote excessive impulsivity or anxiety. However, these processes also depend upon interactions arising between motivational and attentional systems. We discuss these between-system effects by considering the regulation of approach motivation by reactive attentional processes related to fear and by more voluntary processes related to effortful control. It is suggested that anxious and impulsive psychopathology may reflect limitations in these dual means of control, which can take the form of overregulation as well as underregulation.