Developmental Psychopathology

By definition, risk factors increase the likelihood of experiencing psychological difficulties. Family risk factors include child maltreatment, parental rejection, lax supervision, inconsistent or harsh discipline practices, parental conflict, unsupportive family relations, and parental mental illness and substance use. However, exposure to even the most harmful risk factors does not doom all or even most children to a life of psychological problems. Also, children exposed to the same risk factor may have a range of healthy and maladaptive psychological outcomes. For example, although parental depression is one of the most robust risk factors, children of depressed parents exhibit a wide range of adaptive and maladaptive outcomes (e.g., depression, anxiety, aggression, academic problems) (Cummings and Davies 1994). Moreover, exposure to parental mental illness does not affect children in a psychological vacuum. Instead, parental psychopathology (e.g., depression, alcoholism) often co-occurs with other risk factors: familial (e.g., parenting impairments, marital discord, poor parent-child relations); sociocultural (e.g., poverty, community isolation); and biological (e.g., transmission of risk through the operation of genes, birth complications, temperament). These risk factors may contribute to the caustic effects of growing up in depressive or alcoholic families. Consequently, to better understand the development of psychological problems, developmental psychopathologists advocate moving beyond simply identifying individual risk factors that increase the likelihood of disorder to answer more complex questions of: When, how, and why do only some children exposed to risk develop problems?

Mediating mechanisms. The search for mediators answers the question of "how" and "why" risk conditions lead to maladaptive outcomes. Mediators are the processes or mechanisms that explain or account for why family characteristics increase children's risk for psychopathology. Returning to the example of parental depression, a primary goal of a developmental psychopathologist would be to identify the mechanisms by which parental depression leads to child behavior problems. For example, parental depression is associated with increases in parental conflict and poor parenting practices. The stressfulness of experiencing parental conflict and poor parenting practices, in turn, may directly compromise children's mental health. It is also important to understand the mechanisms that underlie or account for the effects of mediating processes. For example, although the focus on parental conflict and poor parenting practices provide part of the answer to why parental depression is a risk factor, we are still not at the level of specifying the response processes in children that ultimately lead to disorder. For example, the stressfulness of parental conflict and poor parenting practices may negatively affect the way children function and cope in various settings (e.g., family, school) on a day-to-day basis. These daily difficulties in functioning in certain settings may eventually grow into disorders that are stable across time and setting.

Moderating conditions. The search for moderators in models of risk answers questions of "who" is a greatest risk and "when" is the risk greatest. Thus, the assumption is that the likelihood that a risk factor leads to disorder varies across different individuals (i.e., who is at greater risk) and conditions (i.e., when is the risk greatest). Answering the question of who is at greatest risk involves searching for attributes of the person (e.g., gender, temperament, personality) that might amplify or increase the likelihood that they will experience a disorder when exposed to risk. For example, parental discord is especially likely to increase psychological problems for children who have difficult, rather than easy, temperaments (Davies and Windle 2001). Attributes outside the person (i.e., family, school, community, peers) may also intensify the effects of the risk factor. For example, Michael Rutter and colleagues (1976) found that the risk for psychopathology in children exposed to any one of six family risk factors (e.g., family discord, maternal psychiatric disorder, family dis-solution) was comparable to risk for children who experienced no risk factors. However, experiencing two or three risk factors increased the incidence of children's psychiatric problems threefold.