title: Neonatal amygdala lesions advance pubertal timing in female rhesus macaques.
abstract: Social context influences the timing of puberty in both humans and nonhuman primates, such as delayed first ovulation in low-ranking rhesus macaques, but the brain region(s) mediating the effects of social context on pubertal timing are unknown. The amygdala is important for responding to social information and thus, is a potential brain region mediating the effects of social context on pubertal timing. In this study, female rhesus macaques living in large, species-typical, social groups received bilateral neurotoxic amygdala lesions at one month of age and pubertal timing was examined beginning at 14 months of age. Pubertal timing was affected in neonatal amygdala-lesioned females (Neo-A), such that they experienced significantly earlier menarche and first ovulation than did control females (Neo-C). Duration between menarche and first ovulation did not differ between Neo-A and Neo-C females, indicating earlier first ovulation in Neo-A females was likely a consequence of earlier menarche. Social rank of Neo-A females was related to age at menarche, but not first ovulation, and social rank was not related to either event in Neo-C females. It is more likely that amygdalectomy affects pubertal timing through its modulation of GABA-ergic mechanisms rather than as a result of the removal of a social-contextual inhibition on pubertal timing.
authors.affiliation: Department of Psychology, Emory University, 36 Eagle Row, Atlanta, GA 30322, United States; Yerkes National Primate Research Center, 954 Gatewood Rd NE, Atlanta, GA 30329, United States. Electronic address: sstephens@ucsd.edu.
authors.forename: Shannon B Z
authors.initials: SB
authors.lastname: Stephens
authors.affiliation: Department of Psychology, Emory University, 36 Eagle Row, Atlanta, GA 30322, United States; Yerkes National Primate Research Center, 954 Gatewood Rd NE, Atlanta, GA 30329, United States. Electronic address: jraper@emory.edu.
authors.forename: Jessica
authors.initials: J
authors.lastname: Raper
authors.affiliation: Department of Psychology, Emory University, 36 Eagle Row, Atlanta, GA 30322, United States; Yerkes National Primate Research Center, 954 Gatewood Rd NE, Atlanta, GA 30329, United States. Electronic address: jbachev@emory.edu.
authors.forename: Jocelyne
authors.initials: J
authors.lastname: Bachevalier
authors.affiliation: Department of Psychology, Emory University, 36 Eagle Row, Atlanta, GA 30322, United States; Yerkes National Primate Research Center, 954 Gatewood Rd NE, Atlanta, GA 30329, United States. Electronic address: kim@emory.edu.
authors.forename: Kim
authors.initials: K
authors.lastname: Wallen
mesh_terms: D000679:Amygdala / Q000187:drug effects / Q000503:physiopathology*; D000818:Animals; D005260:Female; D007051:Ibotenic Acid / Q000633:toxicity; D008253:Macaca mulatta; D010060:Ovulation / Q000187:drug effects / Q000502:physiology*; D012741:Sexual Maturation / Q000187:drug effects / Q000502:physiology*
chemical_list: D007051:Ibotenic Acid
keywords: Amygdala; Menarche; Puberty; Rhesus monkey; Social context