Biopsychosocial and Developmental Approaches in Pediatrics
James C. Harris
When parents bring a child to the pediatrician, it is because they are concerned. Their distress and disquietude must be appreciated, as symptoms are elicited and signs are understood so that a sense of confidence can be established. This allows the parents to confidently carry out the recommendations made for the child’s care and treatment. The approach to the patient is developmental and biopsychosocial in nature. It is an interactional approach, rather than an exclusively reductionist, biomedical one; it addresses current symptoms and physiologic changes, the meaning of the illness to both child and family, their current psychologic state, their history of adaptation to past illnesses, the family genetic background, and their understanding of this particular illness. To develop an appreciation for this approach, developmental models and the interface of brain and behavior are reviewed in this chapter. See the other chapters in this section for a more detailed discussion of the stress response, resilience to stress, coping with stress, bereavement, and stress-related disorders. Later chapters present the epidemiology, assessment, diagnosis, and treatment of emotional, behavioral, and interpersonal conditions in childhood, reviewed from a biopsychosocial perspective. Guidelines for referral to a child and adolescent psychiatrist are presented in Chapter 115. The inclusion of these disorders is in keeping with a pediatric focus on the “New Morbidity” paradigm, which represents a shift in understanding those areas that impact on the health of children and families.
From a personal developmental perspective, the child is viewed as active and fully engaged in life, using his or her individual genetic and temperamental endowments to master developmental tasks in relation to family, peers, and community, even when the child and the family are faced with illness. Psychologic factors may assume importance in altering individual susceptibility to disease and recovery from illness.
Considering children’s behavior more generally, a behavior may be quantitatively different from normal when behaviors that were initially developmentally appropriate persist, as in separation anxiety disorder, or qualitatively different from the average child’s adaptation, as in major depression; both of these perspectives are addressed.
THE DEVELOPMENTAL PERSPECTIVE
The developmental perspective is basic to pediatrics. It emphasizes the capacity for change throughout life, an approach now referred to as the lifespan view of human development. The child is seen as an active, socially oriented, and developing person, rather than as either a passive respondent to the environment or an individual developing independently of the environmental experiences. Development occurs in phases of progressive change as the child masters new developmental tasks. Early experiences are important in this process, but the child has a remarkable resilience to stress, and as new abilities emerge, the child has new means to master environmental challenges.
Growth refers to changes in the size of the body as a whole, and development addresses the differentiation of form (i.e., changes in function shaped by interaction with the external environment). Development is an interactive process and refers, particularly in psychiatry, to emotional and social development. The opportunity to develop one’s full biologic and psychologic potential is a result of many interacting factors. Genetic factors are important in establishing the limits of potential, but they are interwoven with environmental experience. Physical trauma, particularly brain injury, affects development and behavior; nutritional factors are critically important.
A developmental perspective has the following characteristics:
It emphasizes changing contexts and patterns of behavior over time, rather than behavioral stability.
It recognizes that younger children have considerable developmental plasticity in the nervous system, but that with the pruning of neuronal synapses associated with maturation, the brain’s capacity to adapt to injury becomes more circumscribed.
It acknowledges discontinuity in psychologic development, as well as continuity, connectedness, and the persistence of temperamental traits over time.
It appreciates that vulnerabilities to some social experiences exist, but that these experiences may be strengthening as they are mastered.
It appreciates that stressors may have a different effect at one age than at another.
It asks why certain emotional and behavioral disorders present initially at one age and not at another; why are there differences in age of onset of disorder.
It suggests an opportunity for prevention by offering interventions within the developmental period.
It studies how approaches to the interview, diagnosis, and treatment may be better informed by an appreciation of developmental processes, experience, and task mastery.
A developmental perspective also is applied to the study of major mental disorders when they occur during the developmental period. Through the study of developmental psychopathology, the natural history of a major mental illness is studied as it is manifested at different ages and as it influences the mastery of age-appropriate developmental tasks. The capacity to master developmental tasks progresses with age as mental processing becomes more efficient, working memory is enhanced, and thinking becomes more reflective.
From a developmental perspective, the pediatrician considers all the following: the full spectrum of behavior from the molecular level, as seen in enzyme activation in the course of differentiation; the interaction of metabolic and physical changes associated with the development of neurotransmitter and hormonal systems; the development of cognition, intelligence, and the emotions; and individual reciprocal social relationships with family, peers, and community. The last category includes the quality of the interaction of the infant and child with parents, siblings, and others; the child’s role in the family system; and the type of child-rearing practices carried out. Child rearing is influenced by the cultural and personal experiences of the parents.
BRAIN MATURATION
The growth of the brain, in contrast to other organ systems, is greatest during the infant and toddler years. By 6 months of age, the brain has reached half of its mature weight, and by 5 years, 90% of its adult weight. The rapid growth of the brain, in contrast to the rest of the body, has important implications from the developmental perspective. This rapid development has been linked to a maturational view of development that argues that abilities are influenced by experience and that they gradually unfold as long as two primary conditions are met: adequate nutrition and an opportunity to interact in a normal, expected environment.
Some parts of the brain mature earlier than others (e.g., the brainstem and limbic system mature before the cerebellum and higher cortical areas). Hearing and vision are present early, but interpretation and understanding of what is heard or seen takes place later. An understanding of the usual sequences of development is relevant in assessing children with developmental delays, but considerable variability in development occurs (e.g., some children normally do not speak until age 3 or 4 years). Delays are more common in boys than girls, indicating possible gender differences in brain development. The association of developmental delay with maturation is hypothetical, and much more must be learned. In intellectual disability, however, the failure of appropriate maturation or interference with normal brain development is an important hypothesis.
Marked individual differences in brain development occur; therefore, although average ages for maturational events exist, to consider a range of months during which development will occur is important and more appropriate (e.g., walking at 10 to 18 months).
Developing parts of the brain are more susceptible to damage from injury, infection, toxins, or malnutrition at times of their most rapid growth. However, the young brain also is more capable of adapting to injury, so that the practical consequences of damage may be less. This is probably because brain functions are not specifically localized but instead involve connections that are present throughout the brain and involve multiple brain regions. In young children who suffer damage to regions vital to function (e.g., the speech area in the left hemisphere), functional changes in the other hemisphere may compensate for the damage. Recovery from brain injury in young children may be more complete than expected because of this neuronal plasticity.
ENVIRONMENTAL INTERFACE
Development is not only a gradual unfolding, but also a process in which experience plays an important role, and learning requires both brain growth and external stimulation. The timing of development is not controlled entirely by genetics, and external environmental stimulation may be needed to facilitate it. The term plasticity is used to signify the fact that the organism can be modified by environmental experiences. When behavior in response to a stimulus is measured, plasticity is being measured. For example, if infant kittens are reared with one eyelid sutured closed, vision is impaired in that eye; however, the loss is partially functional, and plasticity is demonstrated, because vision can be substantially restored by administering gamma amino butyric acid (GABA) agonists after the sutures are removed.
The chemistry of brain development also is affected by deprivation, just as in adults the lack of use of an extremity leads to some muscle wasting. Lack of stimulation may retard growth, but extra stimulation does not enhance it if adequate maturation has not occurred. Stimulation may influence particular behaviors at the appropriate time (e.g., babbling in infants is influenced by parents’ talking to them and accommodating the prosody or rhythm of their voice to that of the infant). Children who receive specific language training in a day-care center have enhanced abilities compared with those who are involved in free play alone. Stress may interfere with development, as demonstrated by the persistence of enuresis in children with severe burns and the return to bed-wetting in children who have been stressed.
DEVELOPMENTAL TASKS
The development of the person, the personality, has been the focus of developmental theorists. Theoretic perspectives have addressed psychosexual development, cognitive development, the development of interpersonal relations, and identity. Psychotherapies have been suggested based on these approaches. Current emphasis is placed on an ethologic model of development that addresses behavior in reference to our biologic background, those patterns of behavior across species that serve the same purpose, the natural selection of behavioral traits, and behavior that is biologically based, such as infant–mother attachment.
Each of the frameworks for development makes assumptions about the capabilities of the infant and young child in regard to recognition and remembrance of past experience, temperamental characteristics, and response to environmental uncertainty. Each of these perspectives suggests an emphasis on socially important features or goals (e.g., self-control, moral development, compassionate interpersonal behavior, and self-awareness are ideal goals). These goals represent developmental tasks to be mastered at different ages.
The child is an active person who masters a series of developmental tasks that meld genetic and temperamental attributes while utilizing psychosocial support (e.g., infants and children are actively involved, capable of interaction, and have individual responses). Infants influence what goes on around them and what happens to them by their behavior; parents respond to their infants’ preferences. This is in contrast to an older view that depicted the infant as passive, without individuality, and at the mercy of the environment. The parent–child interaction is one of social reciprocity, as the parents adapt to the child through their individual personalities, past experience with children, and family background. This past interactional history is particularly important to understand in the parents’ response to a handicapped or premature child.
DEVELOPMENTAL MODELS OF BEHAVIORAL AND EMOTIONAL DEVELOPMENT
To understand the complex interaction between children and the biologic and environmental influences on them, the child’s development can be approached from several perspectives.
Biologic Models
Maturational Model
The maturational view, which was popularized by Gesell, states that development occurs through orderly, nonrandom, patterned sequences determined by biologic and evolutionary history. However, the rate of development is influenced by the individual genetic family history. Although development may be altered by such things as illness, malnutrition, or stressful experiences, fundamental biologic factors direct it. A favorable environment facilitates development; an unfavorable one inhibits development. Neither circumstance changes the basic biologic potential. Gesell sought to describe the form of morphologic or structural growth and psychologic growth. He argued that development has direction (e.g., cephalocaudal and proximodistal), is organized through reciprocal relationships or interweavings (e.g., flexors and extensors develop in a sequence that allows coordinated movement), and may demonstrate functional asymmetry or an unbalanced development that occurs to achieve mastery at a later stage of development (e.g., development of “handedness”).
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
