The Biopsychosocial Model: Understanding Multiple, Interactive Influences on Child Development and Behavior

Bronfenbrenner’s Ecological Systems Theory

Urie Bronfenbrenner’s ecological systems theory ( ) proposes there are multiple levels of influence on a child’s development, spanning from relationships with caregivers to systems such as schools and workplaces, to events in the broader society ( Fig. 2.1 ). The microsystem describes the direct relationships and interactions children have, such as with caregivers, siblings, and peers. These individuals directly influence the child by scaffolding development, providing opportunities to play and learn, and providing emotional support to children. The microsystem also contains structures with which the child interacts, such as school, neighborhood, childcare settings, and family. Children both influence and are influenced by these relationships and structures (e.g., a child’s temperament may contribute to setting the tone of a classroom). The mesosystem describes interaction among the structures that are in the microsystem (e.g., bidirectional influences between neighborhoods and schools). The exosystem consists of larger social systems that impact structures in the microsystem (e.g., community-based family resources or parental work schedules). Children do not directly interact with the exosystem, but they experience the impact of changes in these social systems. The macrosystem is the outermost layer of a child’s environment and is defined by cultural values, customs, and laws that influence the ways that the inner layers function. The chronosystem captures the influence of time on children’s development, reflecting both developmental processes that take place over time and the changing influence of events (e.g., a traumatic event) based on their duration and the developmental stage in which they occur.

Sameroff’s Transactional Model

Arnold Sameroff’s transactional model builds on Bronfenbrenner’s ideas about the bidirectionality of effects on children’s development. It discusses the processes that take place between parents and children in everyday interactions and over time ( ). This model grew out of observations that many risks, such as premature birth or birth complications, were associated with observable developmental problems only for some children—most often those children with additional social risks (e.g., low socioeconomic status). In other words, children’s environments moderate the effect of early biologic risks on children’s development. Nature and nurture are viewed as inherently inextricable; genes are expressed dependent on one’s environment, and parents respond differently to children based on the child’s inherent biologic characteristics.

An illustration of this cascading effect in a mother-child dyad is shown in Fig. 2.2A . A child’s characteristics impact parenting, and parenting impacts children’s development; these bidirectional cascades of influences continue over time across development. Critically, parents’ behaviors in response to children are driven by their interpretations and the meaning they make from the behavior. For instance, a parent’s anxious handling may arise because of her perception about the child’s birth complications (e.g., “He’s fragile and I might hurt him by accident”); a parent may disengage from a child with a difficult temperament because of the meaning she attaches to the child’s fussy behavior (e.g., “Nothing I do settles him, he must not want me”).

Understanding these processes provides several potential ports of entry for intervention in the parent-child relationship (i.e., the three R s: remediation, redefinition, reeducation); changing any of these ports of entry has the potential to change the sequelae that follow (see Fig. 2.2B ). Remediation refers to directly changing the child. If a child has gastroesophageal reflux that contributes to a difficult temperament, treating the reflux might reduce the child’s fussiness, and in turn, the parent may show more warmth and sensitivity with the child. Such treatment would be indicated when the child’s condition can be effectively treated. However, it is not always feasible to offer treatment, such as when the child’s condition is nonmodifiable or when there are no target symptoms that can be identified in the child that could be changed (e.g., with medical treatment or developmental therapies). Redefinition is changing a parent’s interpretations of, attitudes toward, or beliefs about the child. A clinician may help parents to think about what their child is thinking and feeling during a challenging moment, help parents to reinterpret their child’s behavior (e.g., aggressive behavior might reflect a child’s inability to put words to strong feelings), or reinterpret their role in an interaction with their child (e.g., being a supportive and warm presence can be helpful to your child, even if he doesn’t stop crying right away). This work often happens through parent-child psychotherapy, but modest redefinition can also occur through brief clinician visits. Reeducation refers to directly changing the parents’ skills or knowledge and is most effective when parents’ attitudes and beliefs about the child are healthy, but their parenting approach could be improved (e.g., by providing information about how to position a baby with a physical disability). Remediation, redefinition, and reeducation are inherently intertwined due to the dynamic nature of bidirectional influences in children’s development; a change in one domain will likely have cascading effects in other domains.

Diathesis-Stress Model

This model suggests that some individuals are more vulnerable to the impacts of stress than others ( ) ( Fig. 2.3A ). Diatheses—hereditary or constitutional predispositions—might include biologic, genetic, temperament-related, or cognitive factors that predispose a child to being vulnerable to the influences of stress. Stresses might include discrete life events (e.g., divorce), chronic stresses (e.g., financial strain), or an accumulation of more minor daily stresses (e.g., school assignments). In a developmentally supportive environment, this model suggests that both resilient and vulnerable individuals are likely to do well. In a challenging environment, resilient individuals would do well, whereas vulnerable individuals would not. Those who have greater predispositions to psychopathology may be overwhelmed by a small to moderate environmental stress, whereas individuals with lower predispositions may withstand higher levels of environmental stress without apparent effects on their functioning.

Differential Susceptibility Theory

This theory posits that individuals vary in their plasticity, or their level of susceptibility to environmental influences ( ) (see Fig. 2.3B ). Differential susceptibility can contribute to positive and negative outcomes. Some children, sometimes referred to as “orchids,” are very sensitive to their environment. When they are in an environment that is highly supportive of their development and well-being, they thrive; however, when they are in an environment that is unsupportive of their development, they struggle. Other children, sometimes referred to as “dandelions,” are less susceptible to environmental influences and will do roughly the same regardless of how supportive their environment and relationships are. Children can fall anywhere on the spectrum between these two extremes. This degree of plasticity has been linked to differences in genetic markers, including 5-HTTLPR , DRD4 , and BDNF ( , in press). A child’s susceptibility may differ depending on specific environmental influences and the specific outcome being considered.