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Discovering Our Selves: The Science of Emotion
Executive Summary

Panel: The Affect of Emotions:
Laying the Groundwork in Childhood

"Studying the Causes of Delinquency and Violence"

Felton Earls, M.D., is Professor of Human Behavior and Development in the Department of Maternal and Child Health at the Harvard School of Public Health.

My research--observational rather than experimental--uses an ecological perspective to study the causes of delinquency and violence in modern society. This perspective assumes that human behavior is regulated by the specific attributes of one's social and physical environments, and it requires that the scientist carefully choose the setting in which to study human behavior.

We chose Chicago, in part for its diversity and size, and in part because it shares certain characteristics with other American cities. Chicago has three million people living in groups defined by race, ethnic background, and social class that are strongly stratified, or segregated, within the geographic boundaries of the city's neighborhoods.

Over the latter half of the century, Chicago has experienced economic displacement and population out-migration from the city to the suburbs. This displacement has resulted in a concentration of poverty in the city's interior zones. Simultaneously there has been in-migration: first, of African-Americans from the South; then, beginning in the late 1970s and continuing today, of people from Mexico, Central America, the Caribbean, and Eastern Europe. And finally, over the same period of time, the illegal drug economy has grown rapidly to compromise--if not replace--the legal structures that promoted the city's economic development.

Originally we were determined to look at the causes of delinquency, but as we examined these ecological settings and the children growing up in those settings, our interest inevitably expanded to the relationship between exposure to violence and emotional health.

To find out what it is like to grow up in a city like Chicago and appreciate that the variations among groups are considerable, we focused on two interrelated conditions:

  • the amount of crime and violence displayed at the neighborhood level, as measured by children and adolescents who display such behaviors and admit to them.

  • the types of experiences children have relative to the levels of violence committed in their homes, neighborhoods, and schools; this violence is not necessarily perpetrated by them but they experience it--perhaps as victims--or witness it.

    Since we began collecting data three years ago, we have examined the functional or social organization of more than 300 neighborhoods in tandem with a longitudinal study of individual children, adolescents, and young adults who range in age from birth to 18 years. More than 6,000 children already have been assessed comprehensively and are now being examined a second time for the consequences of living in neighborhoods that vary in crime and violence.

    How does the prevailing social environment in the poorer parts of inner city Chicago--declining resources, physical blight, and epidemic levels of violence--shape children's emotions and behaviors? In addition to characterizing neighborhoods, we designed measures of children's exposure to violence: seen someone shoved, kicked, or punched; seen someone attacked with a knife; heard a gunshot; seen someone shot. We have found that more than 90 percent of kids report that by age 15 they have witnessed some form of violence. Indeed, more than 75 percent report witnessing some form of violence by age 9.

    At the same time, we are examining how neighborhoods actually function in terms of relationships between people. In other words: Rather than mapping race, ethnicity, and social class, we are mapping trust and reciprocity among neighbors, a measure we call "collective efficacy." What our new maps show is high collective efficacy in the parts of the city nearest the suburbs, and, with few exceptions, low levels in the central city. Concentrated poverty, in particular, undermines collective efficacy. Where collective efficacy is lowest, violence and delinquency are highest.

    Our longitudinal study will help us look at the individuals growing up in those neighborhoods and determine what kind of social or ecological mechanisms influence families in regulating, guiding, and supervising children. How do children's individual differences interact with the systems of families and schools and neighborhoods in which they are embedded? We are studying infants, and we will be able to study them into adolescence.

    The study is still evolving, but the mounting evidence is that these neighborhood effects are very important. Whether a neighborhood functions with high or low collective efficacy has a great impact on its children.

    This is important because cities, despite concerns about security and safety, are the choice of people throughout the world. Within ten years, between 70 and 75 percent of the world's population will live in cities. While it can be argued that the primary incentives for this choice are social rather than economic ones, we are going to need to find ways to regulate our social environments in a way that makes them safe and secure.

    UNICEF has embarked on a campaign to encourage cities to become "child-friendly" by developing resources that not only enhance skill development but make places safe for children. We find this concept intellectually compelling and quite useful as we begin to think about using our data to inform policy.

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