title: Sexually Dimorphic Risk Mitigation Strategies in Rats.
abstract: The scientific understanding of fear and anxiety-in both normal and pathological forms-is presently limited by a predominance of studies that use male animals and Pavlovian fear conditioning-centered paradigms that restrict and assess specific behaviors (e.g., freezing) over brief sampling periods and overlook the broader contributions of the spatiotemporal context to an animal's behavioral responses to threats. Here, we use a risky "closed economy" system, in which the need to acquire food and water and the need to avoid threats are simultaneously integrated into the lives of rats, to examine sex differences in mitigating threat risk while foraging. Rats lived for an extended period (∼2 months) in enlarged chambers that consisted of a safe, bedded nest and a risky foraging area where footshocks could be delivered unpredictably. We observed that male and female rats used different strategies for responding to the threat of footshock. Whereas male rats increased the size of meals consumed to reduce the overall time spent foraging, female rats sacrificed their metabolic needs in order to avoid shocks. Ovarian hormone fluctuations were shown to exert slight but reliable rhythmic effects on risky decision-making in gonadally intact female rats. However, this did not produce significant differences in approach-avoidance trade-offs between ovariectomized and intact female groups, suggesting that male-female sex differences are not due to the activational effects of gonadal hormones but, rather, are likely to be organized during early development.
authors.affiliation: Department of Psychology, University of Washington , Seattle, Washington 98195-1525.
authors.forename: Blake A
authors.initials: BA
authors.lastname: Pellman
authors.affiliation: Department of Psychology, University of Washington , Seattle, Washington 98195-1525.
authors.forename: Bryan P
authors.initials: BP
authors.lastname: Schuessler
authors.affiliation: Department of Psychology, University of Texas at Austin , Austin, Texas 78712.
authors.forename: Mohini
authors.identifier: 0000-0002-3031-5412
authors.initials: M
authors.lastname: Tellakat
authors.affiliation: Department of Psychology, University of Washington, Seattle, Washington 98195-1525; Program in Neuroscience, University of Washington, Seattle, Washington 98195-1525.
authors.forename: Jeansok J
authors.identifier: 0000-0001-7964-106X
authors.initials: JJ
authors.lastname: Kim
mesh_terms: D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects / Q000502:physiology*; D003214:Conditioning, Classical / Q000502:physiology*; D003346:Corticotropin-Releasing Hormone / Q000008:administration & dosage; D004597:Electroshock / Q000379:methods; D030762:Estrous Cycle; D005108:Extinction, Psychological / Q000187:drug effects / Q000502:physiology*; D005239:Fear / Q000523:psychology*; D005247:Feeding Behavior / Q000187:drug effects; D005260:Female; D005583:Fourier Analysis; D006728:Hormones / Q000494:pharmacology; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D009043:Motor Activity / Q000187:drug effects / Q000502:physiology; D010052:Ovariectomy; D051381:Rats; D020318:Rats, Long-Evans; D012055:Reinforcement Schedule; D012727:Sex Characteristics; D013997:Time Factors
chemical_list: D006728:Hormones; D003346:Corticotropin-Releasing Hormone
keywords: anxiety; decision-making; fear; foraging behavior; sex differences 