title: Switching between forest and trees: opposite relationship of progesterone and testosterone to global-local processing.
abstract: Sex differences in attentional selection of global and local components of stimuli have been hypothesized to underlie sex differences in cognitive strategy choice. A Navon figure paradigm was employed in 32 men, 41 naturally cycling women (22 follicular, 19 luteal) and 19 users of oral contraceptives (OCs) containing first to third generation progestins in their active pill phase. Participants were first asked to detect targets at any level (divided attention) and then at either the global or the local level only (focused attention). In the focused attention condition, luteal women showed reduced global advantage (i.e. faster responses to global vs. local targets) compared to men, follicular women and OC users. Accordingly, global advantage during the focused attention condition related significantly positively to testosterone levels and significantly negatively to progesterone, but not estradiol levels in a multiple regression model including all naturally cycling women and men. Interference (i.e. delayed rejection of stimuli displaying targets at the non-attended level) was significantly enhanced in OC users as compared to naturally cycling women and related positively to testosterone levels in all naturally cycling women and men. Remarkably, when analyzed separately for each group, the relationship of testosterone to global advantage and interference was reversed in women during their luteal phase as opposed to men and women during their follicular phase. As global processing is lateralized to the right and local processing to the left hemisphere, we speculate that these effects stem from a testosterone-mediated enhancement of right-hemisphere functioning as well as progesterone-mediated inter-hemispheric decoupling.
authors.affiliation: Department of Neurobiology & Behavior, University of California, Irvine, USA; Center for Neurobiology of Learning & Memory, University of California, Irvine, USA; Department of Psychology, University of Salzburg, Austria; Center for Cognitive Neuroscience, University of Salzburg, Austria. Electronic address: Belinda.Pletzer@sbg.ac.at.
authors.forename: Belinda
authors.initials: B
authors.lastname: Pletzer
authors.affiliation: Department of Neurobiology & Behavior, University of California, Irvine, USA; Center for Neurobiology of Learning & Memory, University of California, Irvine, USA.
authors.forename: Ourania
authors.initials: O
authors.lastname: Petasis
authors.affiliation: Department of Neurobiology & Behavior, University of California, Irvine, USA; Center for Neurobiology of Learning & Memory, University of California, Irvine, USA.
authors.forename: Larry
authors.initials: L
authors.lastname: Cahill
mesh_terms: D001288:Attention / Q000187:drug effects; D003278:Contraceptives, Oral, Hormonal / Q000494:pharmacology*; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D005498:Follicular Phase / Q000523:psychology; D007839:Functional Laterality / Q000187:drug effects; D012739:Gonadal Steroid Hormones / Q000378:metabolism; D006801:Humans; D008183:Luteal Phase / Q000523:psychology; D008297:Male; D010775:Photic Stimulation; D011374:Progesterone / Q000378:metabolism*; D011597:Psychomotor Performance / Q000187:drug effects; D021641:Recognition, Psychology / Q000187:drug effects; D012727:Sex Characteristics; D013739:Testosterone / Q000378:metabolism*; D055815:Young Adult
chemical_list: D003278:Contraceptives, Oral, Hormonal; D012739:Gonadal Steroid Hormones; D013739:Testosterone; D011374:Progesterone; D004958:Estradiol
keywords: Attention; Global–local processing; Hemispheric asymmetries; Menstrual cycle; Sex differences; Sex hormones