Developmental changes of rhesus monkeys in response to separation from the mother.
The development of separation response behaviors in infant rhesus macaques across the first 6 months of life was assessed. Seventeen infants underwent a neonatal assessment at 7, 14, 21, and 30 days of age which included a brief period of social isolation. At 3 and 6 months of age these same monkeys and four additional subjects were again subjected to a period of brief social isolation and also exposed to a novel environment with their sedated mother. Results indicate a developmental increase followed by a steady decline in the frequency of separation vocalizations. A modest relationship between early-infancy locomotor profiles and separation responses was also observed at several time points suggesting a possible relationship between these measures. However, stable inter-individual measures of separation distress did not emerge until late in the infantile period. This could suggest that high levels of maternal contact-seeking behavior early in infancy are context specific and not a reliable index of enduring temperament.
Section on Developmental Affective Neuroscience, National Institute of Mental Health, 9000 Rockville Pike, Bethesda, MD 20892, USA.
Bo
B
Zhang
Benjamin
B
Suarez-Jimenez
Amanda
A
Hathaway
Carlos
C
Waters
Kelli
K
Vaughan
Pamela L
PL
Noble
Nathan A
NA
Fox
Stephen J
SJ
Suomi
Daniel S
DS
Pine
Eric E
EE
Nelson
D000818:Animals; D001010:Anxiety, Separation / Q000523:psychology*; D001522:Behavior, Animal / Q000502:physiology; D005260:Female; D008253:Macaca mulatta / Q000502:physiology / Q000523:psychology*; D008297:Male; D008426:Maternal Deprivation; D009043:Motor Activity / Q000502:physiology; D009769:Object Attachment; D012919:Social Behavior; D012934:Social Isolation; D014828:Vocalization, Animal