Scientific basis

The effects of health care, nutrition, and mental stimulation on children's mental and emotional growth-as reflected in their ability to master ever more complex activities-and physical growth are synergistic and cannot be broken up into separate domains. Integrated programs therefore seek to address all of children's basic needs. In addition to food, protection, and health care, child care programs must also provide affection, intellectual stimulation, supportive human interaction, and opportunities and activities that promote learning.

Studies conducted in the United States during the 1960s to the mid 1970s confirmed that intervention early in a child's life has lasting positive effects. With the basic question of long-term efficacy resolved, a second wave of studies was free to investigate the effects produced by different program models. Current research in the field seeks to build on these findings, to identify more precisely what makes small-scale programs effective, and to devise ways to expand them to a national scale (Mitchell, Weiss, and Schultz 1992).

The crucial early years. Medical and educational research have both shown that mental growth-that is, the development of intelligence, personality, and social behavior-occurs most rapidly in humans during their earliest years. It is estimated, in fact, that half of all intellectual development potential is established by age four (Bloom 1964). It is also now known that the brain responds most to very early experience, and brain research has documented the environment's effect on brain function. Because of the importance of the early years, intervention even in kindergarten may be too late to help develop young children's capacities. By contrast, the effectiveness of quality early child development programs in spurring children's mental, emotional, and physical development has been documented by the past thirty years of research.

According to the Carnegie Task Force on Meeting the Needs of Young Children (1994):

· Brain development before age one is more rapid and extensive than was previously realized. Although cell formation is virtually complete before birth, brain maturation continues after birth.

· Brain development is much more vulnerable to environmental influence than was suspected. Inadequate nutrition before birth and in the first years of life can seriously interfere with brain development and lead to such neurological and behavioral disorders as learning disabilities and mental retardation.

· The influence of early environment on brain development is long lasting. There is considerable evidence showing that infants exposed to good nutrition, toys, and playmates had measurably better brain function at twelve years of age than those raised in a less stimulating environment.

· Environment affects not only the number of brain cells and the number of connections among them but also the way these connections are "wired." The process of eliminating excess neurons and synapses from the dense, immature brain, which continues well into adolescence, is most dramatic in the early years of life, and it is guided to a large extent by the child's sensory experience of the outside world.

· Early stress can affect brain function, learning, and memory adversely and permanently. New research provides a scientific basis for the long recognized fact that children who experience extreme stress in their earliest years are at greater risk for developing a variety of cognitive, behavioral, and emotional difficulties later in life.

Box 1 Five reasons to invest in young children

To build human resources in a scientifically proven manner. Research has shown that half of a person's intelligence potential is developed by age four and that early childhood interventions can have a lasting effect on intellectual capacity, personality, and social behavior. Integrated programs that target children in their very early years are therefore critical for their mental and psychosocial development

To generate higher economic returns and reduce social costs. By increasing children's desire and ability to ream, investment in early child education can increase the return on investment in their later education by making that education more effective. It can also enable participants to earn more and can raise their productivity in the workforce. Early investment in children can reduce the need for public welfare expenditures later and cut down on the social and financial costs associated with grade repetition, juvenile delinquency, and drug use.

To achieve greater social equity. Integrated programs for young children can modify the effects of socioeconomic and gender-related inequities, some of the most entrenched causes of poverty. Studies from diverse cultures show that girls enrolled in early childhood programs are better prepared for school and frequently stay in school longer. Early childhood interventions also free older sisters from the task of tending preschoolers, so that they can to return to school.

To increase the efficacy of other investments. Including early childhood interventions in larger programs can enhance the programs' efficacy. Early childhood interventions in health and nutrition programs increase children's chances of survival. Interventions in education programs prepare children for school, improving their performance and reducing the need for repetition.

To help mothers as well as children. With ever more mothers working and more households headed by women, safe child care has become a necessity. Providing safe child care allows women the chance to continue their education and learn new skills.

Helping parents meet their children's changing developmental needs. The younger the child, the more difficult it is to identify precisely which physiological and psychological factors govern health, and children's needs in these areas change as they progress from infancy to toddlerhood to preschool to primary school.

As a child becomes a toddler, for instance, most important is to provide a safe, clean environment and proper food. But because feeding is an interactive as well as a physical process, even so straightforward a need as nutrition has psychological aspects. Lack of proper handling and affection has been shown to cause children's growth to falter just as much as lack of proper food.

Parents, especially those who are young and inexperienced, are too often unaware of the fundamental needs of a young child and of the many simple ways available to meet them. Many get their first lessons in constructive child care through early child development programs.

By the same token, only with whole-hearted parental participation can such programs succeed. Both studies and field experience have shown that parental involvement in preschool programs, for instance, results in more and more timely school enrollments and better attendance rates overall. Not surprisingly, therefore, where both parents and infants are targeted-as in Colombia's Programa pare el Mejoramiento de la Educatión, la Salud, y el Ambienta (Promesa) and in Haryana, India-dropout rates have declined dramatically. Parental involvement appears to be essential, moreover, if gains from preschool interventions are to be sustained.