title: Progestogens' effects and mechanisms for object recognition memory across the lifespan.
abstract: This review explores the effects of female reproductive hormones, estrogens and progestogens, with a focus on progesterone and allopregnanolone, on object memory. Progesterone and its metabolites, in particular allopregnanolone, exert various effects on both cognitive and non-mnemonic functions in females. The well-known object recognition task is a valuable experimental paradigm that can be used to determine the effects and mechanisms of progestogens for mnemonic effects across the lifespan, which will be discussed herein. In this task there is little test-decay when different objects are used as targets and baseline valance for objects is controlled. This allows repeated testing, within-subjects designs, and longitudinal assessments, which aid understanding of changes in hormonal milieu. Objects are not aversive or food-based, which are hormone-sensitive factors. This review focuses on published data from our laboratory, and others, using the object recognition task in rodents to assess the role and mechanisms of progestogens throughout the lifespan. Improvements in object recognition performance of rodents are often associated with higher hormone levels in the hippocampus and prefrontal cortex during natural cycles, with hormone replacement following ovariectomy in young animals, or with aging. The capacity for reversal of age- and reproductive senescence-related decline in cognitive performance, and changes in neural plasticity that may be dissociated from peripheral effects with such decline, are discussed. The focus here will be on the effects of brain-derived factors, such as the neurosteroid, allopregnanolone, and other hormones, for enhancing object recognition across the lifespan.
authors.affiliation: Dept. of Psychology, The University at Albany-SUNY, Albany, NY 12222, USA; The Center for Life Sciences Research, The University at Albany-SUNY, Albany, NY 12222, USA; Institute of Arctic Biology, The University of Alaska-Fairbanks, Fairbanks, Alaska 99775, USA; The University of Alaska-Fairbanks, IDeA Network of Biomedical Excellence (INBRE), Fairbanks, Alaska 99775, USA; Cognitive Science Department, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
authors.forename: Alicia A
authors.initials: AA
authors.lastname: Walf
authors.affiliation: Dept. of Psychology, The University at Albany-SUNY, Albany, NY 12222, USA; Institute of Arctic Biology, The University of Alaska-Fairbanks, Fairbanks, Alaska 99775, USA; The University of Alaska-Fairbanks, IDeA Network of Biomedical Excellence (INBRE), Fairbanks, Alaska 99775, USA.
authors.forename: Carolyn J
authors.initials: CJ
authors.lastname: Koonce
authors.affiliation: Dept. of Psychology, The University at Albany-SUNY, Albany, NY 12222, USA; Dept. of Biological Sciences, The University at Albany-SUNY, Albany, NY 12222, USA; The Center for Neuroscience, The University at Albany-SUNY, Albany, NY 12222, USA; The Center for Life Sciences Research, The University at Albany-SUNY, Albany, NY 12222, USA; Department of Chemistry and Biochemistry, The University of Alaska-Fairbanks, Fairbanks, Alaska 99775, USA; Institute of Arctic Biology, The University of Alaska-Fairbanks, Fairbanks, Alaska 99775, USA; The University of Alaska-Fairbanks, IDeA Network of Biomedical Excellence (INBRE), Fairbanks, Alaska 99775, USA. Electronic address: cheryl.a.frye@gmail.com.
authors.forename: Cheryl A
authors.initials: CA
authors.lastname: Frye
mesh_terms: D000375:Aging / Q000187:drug effects / Q000502:physiology* / Q000523:psychology*; D000818:Animals; D006801:Humans; D008568:Memory / Q000187:drug effects / Q000502:physiology*; D011374:Progesterone / Q000378:metabolism* / Q000494:pharmacology; D011581:Psychological Tests
chemical_list: D011374:Progesterone
keywords: Aging; Allopregnanolone; Hippocampus; Hormones; Neurosteroid; Progesterone