Risk and resilience: early manipulation of macaque social experience and persistent behavioral and neurophysiological outcomes.
OBJECTIVE
To review the contributions of research on nonhuman primates, specifically macaque monkeys, to the understanding of early social stress and its effects on behavior and neurophysiology.


METHODS
Review and synthesis of two bodies of work on macaque monkeys and early social manipulation: peer rearing and variable foraging demands. The literature was searched with Medline using key terms macaque, variable foraging, and peer rearing. The reference lists of these articles were also used to generate potential studies for review.


RESULTS
Nonhuman primate macaques show similarities to humans in their social development and functioning. Peer rearing of young macaques and rearing of young macaques with mothers experiencing variable foraging conditions both result in increased anxious, impulsive, and aggressive temperament and behavior; more reactive stress physiology; altered neurotransmitter functioning; and immune and metabolic changes. Functional variants of specific genes that code for neuromodulators are mediators of these effects.


CONCLUSIONS
Disrupted social relations during macaque rearing contribute to the risk for developing emotional and neurophysiological disturbance. In the face of such disruption, certain genotypes contribute to resilience. This can be alternately stated that, for animals of high-risk genotypes, resilience is conferred by quality relationships during rearing. This interaction of genetics with early social environment also applies to child mental health, implicating biological mediators identified in macaques as contributing to more complex outcomes in humans.
Stevens
Hanna E
HE
230 S. Frontage Rd., Yale Child Study Center, New Haven, CT 06520, USA. hanna.stevens@yale.edu
Leckman
James F
JF
Coplan
Jeremy D
JD
Suomi
Stephen J
SJ
D000293:Adolescent; D000294:Adolescent Behavior / Q000502:physiology / Q000523:psychology*; D000818:Animals; D002648:Child; D002652:Child Behavior / Q000502:physiology / Q000523:psychology*; D002657:Child Development / Q000502:physiology*; D002668:Child Rearing / Q000523:psychology*; D002675:Child, Preschool; D005838:Genotype; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008251:Macaca; D009034:Mother-Child Relations; D009482:Neurophysiology; D018377:Neurotransmitter Agents / Q000235:genetics; D055500:Resilience, Psychological; D012306:Risk; D012307:Risk Factors; D012919:Social Behavior; D012931:Social Environment; D013315:Stress, Psychological; D013694:Temperament / Q000502:physiology
D018377:Neurotransmitter Agents