Early childhood events & relationships

Environments that are stressful or deprive young children of psychosocial development may influence individuals to have aggressive tendencies and other violent behaviors later on in life.
Cover "Pathways to Peace: The Transformative Power of Children & Families."
Cover "Pathways to Peace: The Transformative Power of Children & Families." © 2014 Courtesy MIT Press

Chapter 8. Comparative and evolutionary perspectives

Dario Maestripieri

Any effort to understand or shape human behavior must take into consideration the notion that there are universal tendencies to behave in particular ways, which are shared by all human beings, as well as differences in the extent to which these tendencies are expressed in particular individuals. Taking a comparative and an evolutionary perspective can help us understand the universal aspects of human aggressive and peaceful tendencies as well as their variation among individuals. Human aggressiveness has a biological basis, but it is neither necessary nor inevitable. Aggressive competition is common in some animal species but uncommon in others, depending on the ratio between the benefits of aggression (obtaining resources or status) and its costs (physical, physiological, psychological, or social). Humans have a high potential for aggression, but aggressive tendencies can be suppressed in particular environmental circumstances. Individuals living in different environments adopt slow or fast life history strategies that make them adapted to those environments. The quality of the early environment, including social experience, is a key determinant of life history strategies. selfish, exploitative, and aggressive tendencies are more common in individuals with fast life histories who are exposed to early stress, violence, harsh parenting, or unpredictable changes in their environment.

Comparative research on animal behavior can provide the theoretical framework for understanding the effects of early experience on the development of aggressiveness and peacefulness as well as elucidate some of the physiological or social mechanisms underlying these effects. Rhesus macaque females exposed to harsh and abusive parenting in the first few months of life show anxiety, impulsiveness, and abusive parenting in adulthood. They also reach puberty earlier, are more interested in infants, and tend to be more fertile but die at a younger age than other females. Rhesus macaques raised by nurturing mothers who provide emotional and social support, but also encourage their independence, show normal maternal behavior in adulthood and greater resilience in response to stressful challenges. Even species-typical aggressive tendencies can be reduced through manipulation of the early social environment. Young rhesus macaques with high propensities for aggression can acquire effective skills for peaceful conflict resolution after cohabitation with young stumptail macaques, a species in (p.132) which peaceful conflict management and resolution are more common. The findings of comparative research are therefore consistent with those of research in developmental psychology in indicating that a supportive family1 environment and positive experiences acquired during child development are important prerequisites for the creation of peaceful and resilient adults.

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Chapter 9. The problem of institutionalization of young children and its consequences for efforts to build peaceful societies

Nathan A. Fox, Charles A. Nelson, & Charles H. Zeanah

Institutionalization of children is a worldwide problem. The consequences of these deprived early experiences have been known for some time. Indeed, neuroscientists have long been aware of the effects of early adverse experience, particularly profound deprivation, on the developing brain. However, the majority of work to date has focused on examining the effects of experience on brain and brain development in rodents and nonhuman primates. In a rigorous attempt to examine how profound early neglect impacts the course of human development, we designed the Bucharest Early Intervention Project. The Bucharest Early Intervention Project is the first randomized controlled trial of family care intervention on young children institutionalized in infancy. The study is unique in that it includes measures of brain structure and function. Results suggest that early psychosocial deprivation has profound effects on gray matter structure that do not appear to remediate, although subtle intervention effects were observed for white matter volume. EEG activity was significantly affected by early psychosocial deprivation, but there appeared to be remediation of this functioning by the time children were eight years old and had spent close to six or seven years in families. The data from this project argue for changes in the manner in which societies address abandoned children. An important step toward building just and peaceful societies is to provide family-type care for young children instead of institutional life, as being raised in a family1 greatly (p.146) enhances a child’s skills in emotion regulation. The link to peaceful societies is through these processes.

For more information on chapter, “The problem of institutionalization of young children and its consequences for efforts to build peaceful societies”, please visit our resource library.

Chapter 10. Prosocial development and situational morality: Neurobiological, parental, and contextual factors

Marinus H. van IJzendoorn, & Marian J. Bakermans-Kranenburg

Prosocial behavior is any (voluntary) behavior intended to benefit others, and it is one of the potential contributions that an individual can make toward a more peaceful world. In this chapter, neurobiological, parental, and situational factors that might shape the prosocial behavior of children are discussed and emerging prosocial and antisocial behavior in infancy is reviewed and the question posed whether prosociality is inborn or obtained through socialization by parents. Twin studies suggest a considerable genetic component in prosociality, but current molecular genetic studies fail to support this outcome. Studies on gene-environment interaction, in particular on differential susceptibility, might be more promising as the influence of the family1 and wider social context on prosocial development seems undeniable. Hormonal influences on prosocial behavior have recently been studied using intranasal oxytocin administration, and some studies on prosociality related to neural activity and brain morphology in children have become available. This chapter ends with some thoughts and findings on situational morality. Environmental “nudges” might play a more important role than is currently acknowledged in child development research and theories of prosociality.

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Chapter 11. How do events and relationships in childhood set the stage for peace at personal and social levels?

Howard Steele, Marinus H. van IJzendoorn, Marian J. Bakermans-Kranenburg, W. Thomas Boyce, Mary Dozier, Nathan A. Fox, Heidi Keller, Dario Maestripieri, Paul Odhiambo Oburu, & Hiltrud Otto

This chapter focuses on early childhood experiences and how they may contribute to cooperative and peaceful behaviors and outcomes in the later childhood years and into adulthood. Five interrelated topics are explored: (a) universal tensions ever pushing us toward competition or cooperation; (b) socioeconomic inequities that powerfully constrain children’s (and adult’s) potential to contribute to and participate in a healthy and peaceful society; (c) the protective and enabling forces of the early caregiving environment when it is sensitive and responsive to children’s needs; (d) the malevolent, if culturally understandable, influences of harsh parenting practices and child abuse; and (e) a summary of early psychological interventions that promote sensitive parenting and secure attachments well known to be associated with cooperative, nonviolent behaviors across childhood and beyond. Each section is punctuated by suggestions for further research and public policy developments (national and international) that could further advance the cause of peace.

For more information on chapter, “How do events and relationships in childhood set the stage for peace at personal and social levels?”, please visit our resource library.

Chapter abstracts reprinted courtesy of the MIT Press.


James F. Leckman, Catherine Panter-Brick, and Rima Salah (eds.), Pathways to Peace: The Transformative Power of Children and Families , © 2014 Massachusetts Institute of Technology and the Frankfurt Institute for Advanced Studies. 


  1. Frankfurt Institute for Advanced Studies (FIAS) 
  2. The MIT Press 
  3. The Strüngmann Forum Reports series


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