title: The effects of neonatal amygdala or hippocampus lesions on adult social behavior.
abstract: The present report details the final phase of a longitudinal evaluation of the social behavior in a cohort of adult rhesus monkeys that received bilateral neurotoxic lesions of the amygdala or hippocampus, or sham operations at 2 weeks of age. Results were compared to previous studies in which adult animals received amygdala lesions and were tested in a similar fashion. Social testing with four novel interaction partners occurred when the animals were between 7 and 8 years of age. Experimental animals interacted with two male and two female partners in two conditions - one in which physical access was restricted (the constrained social access condition) and a second in which physical access was unrestricted (the unconstrained social access condition). Across conditions and interaction partners, there were no significant effects of lesion condition on the frequency or duration of social interactions. As a group, the hippocampus-lesioned animals generated the greatest number of communicative signals during the constrained social access condition. Amygdala-lesioned animals generated more frequent stress-related behaviors and were less exploratory. Amygdala and hippocampus-lesioned animals demonstrated greater numbers of stereotypies than control animals. Subtle, lesion-based differences in the sequencing of behaviors were observed. These findings suggest that alterations of adult social behavior are much less prominent when damage to the amygdala occurs early in life rather than in adulthood.
authors.affiliation: Department of Psychology and the California National Primate Research Center, University of California, Davis, United States. Electronic address: eblissmoreau@ucdavis.edu.
authors.forename: Eliza
authors.initials: E
authors.lastname: Bliss-Moreau
authors.affiliation: Department of Psychology and the California National Primate Research Center, University of California, Davis, United States.
authors.forename: Gilda
authors.initials: G
authors.lastname: Moadab
authors.affiliation: Department of Psychology and the California National Primate Research Center, University of California, Davis, United States.
authors.forename: Anthony
authors.initials: A
authors.lastname: Santistevan
authors.affiliation: Department of Psychiatry and Behavioral Sciences, The MIND Institute, The Center for Neuroscience and the California National Primate Research Center, University of California, Davis, United States.
authors.forename: David G
authors.initials: DG
authors.lastname: Amaral
mesh_terms: D000679:Amygdala / Q000254:growth & development* / Q000473:pathology / Q000503:physiopathology*; D000819:Animal Communication; D000818:Animals; D000831:Animals, Newborn; D004195:Disease Models, Animal; D005106:Exploratory Behavior; D005260:Female; D006624:Hippocampus / Q000254:growth & development* / Q000473:pathology / Q000503:physiopathology*; D006799:Housing, Animal; D007051:Ibotenic Acid; D008253:Macaca mulatta; D008297:Male; D010641:Phenotype; D012919:Social Behavior; D013239:Stereotyped Behavior; D013315:Stress, Psychological
chemical_list: D007051:Ibotenic Acid
keywords: Amygdala; Development; Hippocampus; Macaca mulatta; Rhesus macaque; Social behavior