The Role of Early Experience in Infant Development,
N.A. Fox, L.A. Leavitt, J.G. Warhol, ed, Johnson & Johnson Consumer Companies, Inc, 1999, paper, 302 pp, $15.00.
Jill Slusarski, Creighton University
In January 1999, the Role of Early Experience in Infant Development Conference was held. This conference was a response to the White House Conference on Early Childhood and Brain Development held in the spring of 1995. The White House Conference focused on the importance of the first three years of life in the development of the child. This 1995 conference prompted a concern among developmental psychologists, neuroscientists, and childcare providers. They felt obligated to determine through research how crucial this time from birth to three years of age is for a child. And if crucial, what experiences are needed for a child to develop appropriately. The Role of Early Experience in Infant Development Conference was developed to bring together developmental psychologists, neuroscientists, practicing pediatricians, and nurses working in early childhood development to present a comprehensive view of the current research in their area of expertise. This book is the compilation of the proceedings. The target audience is practitioners in pediatrics.
The organizational structure of the Role of Early Experience in Infant Development is straightforward. There are six sections: 1) Brain Development, 2) Auditory/Language Development, 3) Cognitive Development, 4) Perceptual Development, 5) Biosocial Development, and 6) Discussion. Each section is preceded by the abstracts for each article and followed by full references.
Section 1 provides an overview of neuroanatomy and development. It covers synaptic development and pruning, the effects of early experience on brain growth and development, and plasticity in the developing and mature brain. It is written in very general and basic terms. For example, the authors’ report within five months of conception, 80 billion neurons are formed creating the cerebral cortex. Pruning of synapses may be affected by experience. “Critical periods” are ages of a child in which certain types of learning are enhanced. Strategies for learning and retaining information are also described. These strategies result in synaptic formation. The authors state that a stimulus rich environment will increase dendritic branching and synaptic density. Injury, age, and gender affect experience in brain development, therefore children who have experienced prenatal brain injury may benefit from behavioral therapy.
Section 2 is on language development, the effects of brain injury, the infant’s ability to extract information about language from the environment, and the relationship between the environment and neurodevelopment. The authors state that parents talking to their children and a language-rich school environment positively influence children’s language skills. Between the ages of seven and 11 months, the child develops the ability to distinguish one word from another by segmenting words from speech. Children of different cultures and language backgrounds start life with the same language development. By the end of the first year they have developed the characteristics of their own language. This occurs because of linguistic input and social interaction.
Section 3 covers the effects of early experience on cognitive development, infants acting as active learners of their environment, and the development of the prefrontal cortex. The prefrontal cortex begins to contribute to executive function (focused, sustained attention, working memory, and inhibition of inappropriate actions) as young as nine months and is responsible for solving spatial and memory problems. Therefore, an immature or impaired prefrontal cortex could be part of learning and behavioral problems. By 14 months, infants are already remembering and imitating actions resulting in cultural and social behavior. Also discussed are the competing cognitive/spatial development theories. For development of spatial abilities children simply need a typical environment to explore. Between three and four years of age, children develop abilities to deal with scaling and maps.
Section 4 is about the development of the infant’s perceptual world, specifically face recognition, spatial relations, and future-oriented processing. It begins with a review of the development of face recognition. The perception of spatial relationships is explained to incorporate vision, proprioception, audition, and olfaction. In adults, specialized areas of the brain are used in perception of spatial relationships. Since infants do not have these specialized areas developed yet, it is believed infant spatial recognition is processed using different neural subsystems than adults use. The authors then address development of future-oriented thinking. A child’s development of future-oriented thinking comes from certain behaviors labeled future-oriented processes, such as expectations and intentionality. An infant has visual expectations as early as three months of age, therefore an infant is able to expect predictable events.
Section 5 covers the neural systems supporting early social development, neurohormones developing the mother-infant relationship, and plasticity and behavior outcomes in premature infants. In general, the hormones oxytocin and vasopressin act in the nervous system to assist social bonding. Oxytocin facilitates pair bonding and selective social interactions while vasopressin enhances arousal and increases aggressive behavior. Immediately after birth, interactions between a mother and child cause behavioral and physiological effects. Breastfeeding is one of these interactions. Breastfeeding promotes oxytocinergic mechanisms and therefore other oxytocin adaptations. Early experiences form bonds, and they decrease the detrimental effects of the immaturity of the neonatal brain of premature infants.
Section 6 is a discussion summarizing the preceding five sections. All the presenters were asked to summarize the core of their presentations and the highlights of those are presented in this final chapter.
This book is a helpful resource on the role of early childhood experience in developmental processes. It is easy to read, yet still holds value in its presentation of technical information. In an effort to compile so much information together, the book compromises extensive discussion of the topics; however, it provides complete references for each work. It covers psychological, social, and perceptual information, which cannot be separated from gross motor skill development. It will help create a holistic view of early experience with children. This book would be a good resource for physicians. It would also be helpful to the pediatric physical therapist.