Research reportFacilitated acquisition of the classically conditioned eyeblink response in females is augmented in those taking oral contraceptives
Research highlights
▶ Females exhibit faster new motor learning than males. ▶ Oral contraceptives facilitate new motor learning.
Section snippets
Participants
Seventy-two participants were recruited from Seton Hall University as a one credit hour requirement for an introductory psychology course. Participant ages and years of education ranged from 18–23 to 12–16, respectively. Women with irregular menstrual cycles were excluded from the study. Informed consent was obtained in accordance with procedures approved by the Seton Hall University Institutional Review Board.
Materials and apparatus
The equipment used for stimulus delivery and assessment of eyelid electromyographic
Acoustic startle responding and pre-pulse inhibition
Regarding the startle response data, a 4 (group) × 2 (intensity) mixed-design ANOVA yielded only a main effect of intensity, F(1,57) = 144.33, p < .001. As expected, larger eyeblink responses were observed in response to the higher intensity acoustic stimulus. As for PPI, a 4 (group) × 2 (IPI) × 2 (intensity) mixed-design ANOVA was conducted. A significant IPI × intensity interaction, F(1,57) = 13.79, was qualified by the triple interaction of group × IPI × intensity, F(3,57) = 4.56, all ps < .001 (see Table 1). For
Discussion
The present study examined associative learning in females currently taking oral contraceptives, females not taking oral contraceptives, and males. The results show that during a classical eyeblink conditioning task, there is a significant sex difference in associative learning acquisition, with females generally learning the CS/US association faster than males and reaching higher asymptotic performance. This difference was driven by the OC group, which demonstrated the highest percentage of
Acknowledgements
The present manuscript was in partial fulfillment of the requirements for a Masters degree from Seton Hall University. The primary author wishes to thank Dr. Janine Buckner for guidance in the study design, approval and execution. Michael T. Bergen and Robert DeMarco helped in the equipment setup and signal processing. Research supported by Department of Veterans Affairs Medical Research Funds and the Stress & Motivated Behavior Institute.
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2024, Progress in Neuro-Psychopharmacology and Biological PsychiatryHormonal contraceptives, stress, and the brain: The critical need for animal models
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2022, Frontiers in NeuroendocrinologyCitation Excerpt :Ovarian hormones also affect performance in specific cognitive tasks (Shively, 2010), and this is a well-researched area wherein HCs exert neurobehavioral effects (reviewed in Warren et al., 2014). Nonspecific OC-use is associated with improved verbal memory (Gogos, 2013; Mordecai et al., 2008); improved, impaired, and no effects on visuospatial tasks (Gogos, 2013; Cicinelli et al., 2011; Griksiene and Ruksenas, 2011); improved or no effects on attentional and working memory tasks (Holloway et al., 2011; Nielsen et al., 2011; Beck et al., 2008); and decreased perseverance on cognitive tasks (Bradshaw et al., 2020). OCs affect emotional memory bidirectionally: HCs improve memory for high-valence emotional events and enhance fear learning (Spalek et al., 2019; Merz et al., 2012), but decrease memory recall for negative emotional events and responsivity/discrimination of fearful stimuli (Person and Oinonen, 2020; Lonsdorf et al., 2015).
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2021, Hormones and BehaviorSex differences and personality in the modulation of the acoustic startle reflex
2018, Physiology and BehaviorCitation Excerpt :For instance, women show increased ASR during the late luteal phase and during ovulation [3]. Besides, the ASR is lower in a prepulse inhibition paradigm for males and for women taking oral contraceptives [37]. However, sex differences in self-reported personality have received much less attention, even though they might contribute as well to explaining the distinct ASR of men and women.