Publications

Click here to view the complete list of Becker Lab publications via Google Scholar.

See below for a selection of recent publications by Dr. Becker, alongside contributions from lab members, alumni, and collaborators.

Mating May Enhance Rapid Formation of Stable Pair Bonds in the Monogamous California Mouse

Robert Roy, Elsa Hammerdahl, Andrew Sage, and Elizabeth Becker

Pair bonds are a hallmark of many monogamous species, yet in the monogamous California mouse (Peromyscus californicus) pair-bond formation is poorly understood. While pair bonds are often assumed to be present after a week of cohabitation, when they actually form in this species is debated. To characterize pair bond latency in California mice, we conducted three-chamber partner preference tests for both males and females following 1, 3, 5, or 7days of cohabitation. Since copulation may contribute to pair-bond formation, animals were paired when females were in estrus and were assessed continuously throughout the cohabitation period for copulatory behavior. We found evidence of pair bonds after 24h of cohabitation for both sexes with no significant changes in partner preference behaviors across cohabitation periods. Focal animals spent more time in the partner's chamber, were more affiliative toward the partner than the stranger and displayed more aggressive behavior toward the stranger. Affiliative behaviors were consistent between the sexes, while males attacked the stranger more frequently and for longer durations than females. Pairs that copulated prior to partner-preference testing spent more time in the partner's chamber and more time huddling, licking, and grooming their mate than those that did not copulate. We conclude that although copulation may not be necessary for pair-bond formation, sexual receptivity at time of pairing is important for the development of these social relationships and that copulation may serve to enhance pair bonds in California mice.

2025

Progesterone Levels in Adolescent Female Athletes May Contribute to Decreased Cognitive Performance During Acute Phase of Sports-Related Concussion

Summer Otta , John Redella , Sukhnandan Cheemaa , Philip Schatzb , and Elizabeth Becker

Although many outcome studies pertaining to sports-related concussion exist, female athletes with concussion remain an understudied group. We examined whether neurocognitive performance in adolescent females with sports-related concussion (SRC) is related to menstrual cycle-related hormone levels measured at one-week post-concussion, one-month postconcussion, or both. Thirty-eight female athletes, ages 14–18, were matched into two groups: SRC or healthy control. Self-reported symptom scores were higher among concussed females in the luteal phase, when progesterone levels are highest. Results suggest that progesterone levels may contribute to a heightened experience of symptoms during the acute phase of SRC, providing further evidence of a possible link between progesterone and symptom scores following concussion.

2024

Recommendations Emerging from Carbon Emissions Estimation of the Society for Neuroscience Annual Meeting

Caroline Kay, Rob Kuper and Elizabeth A. Becker

The annual Society for Neuroscience (SfN) meeting yields significant, measurable impacts that conflict with the environmental commitment of the Society and the Intergovernmental Panel on Climate Change (IPCC) recommendations to address the climate emergency (IPCC, 2018). We used 12,761 presenters’ origins, two online carbon calculators, and benchmark values to estimate 2018 meeting-related travel, event venue operations, and hotel accommodation emissions. Presenters’ conference travel resulted in between 17,298 and 8690 tons of atmospheric carbon dioxide (t CO2), with or without radiative forcing index factors. Over 92% of authors traveled by air and were responsible for >99% of total travel-related emissions. Extrapolations based on 28,691 registrants yielded between 69,592.60 metric tons of carbon dioxide equivalents (t CO2e) and 38,010.85 t CO2 from travel. Comparatively, authors’ and registrants’ hotel accommodation emissions equaled 429 and 965 t CO2e, whereas operation of the San Diego Convention Center equaled ∼107 t CO2e. We relate SfN meeting-related emissions to potential September Arctic Sea ice loss, labor productivity loss in lower-income equatorial countries, and future temperature-related deaths. We estimate emissions reductions of between 23% and 78% by incentivizing between 10% and 50% of the most distant registrants to attend virtually or connecting between two and seven in-person hubs virtually. Completely virtual meetings may yield a reduction of >99% relative to centralized in-person meetings and increase participation of women, queer and transgender scientists, and scientists from low- and middle-income countries. We strongly recommend adopting alternative meeting modes such as four or more in-person global hubs connected virtually by 2030 and fully virtual by 2050.

2023

Virtual Reality Biking Reduces Cortisol Levels and Repetitive Behaviors in Adults with Autism Spectrum Disorder

Cheryl L. George, Amber Valentino, Kimberly D’Anna‑Hernandez, Elizabeth A. Becker

Objectives

Individuals with autism spectrum disorder (ASD) report experiencing stress, which increases with age. Few studies have included the biological stress response for measuring stress. While aerobic exercise can lower stress and repetitive behaviors, motivating adults with disabilities to exercise can be challenging. This study examined whether virtual reality (VR) exercise would improve behavior and stress physiology.

Methods

Seven males with ASD participated. This study employed a single subject withdrawal design, using a baseline phase, followed by alternating intervention (i.e., VR biking) and withdrawal (i.e., no exercise) conditions. Frequency and/or duration of repetitive behaviors were assessed. Pre-post intervention hair cortisol and salivary cortisol for each phase were collected.

Results

Overall, repetitive behaviors were lower in the final phase (M = 24.28, SD = 2.42) compared to baseline (M = 36.68, SD = 5.33). There was no significant difference in basal T1 cortisol levels across phases (χ2(6) = 2.571, p < .276); however, four participants showed cortisol levels that decreased markedly following the first intervention and remained low for the duration of the study. There was a significant difference in the cortisol levels of participants by pre and post intervention status (first intervention phase, B) as measured by AUCg (χ2(1) = 7.00, p < .008).

Conclusions

This study demonstrates that exercise can have acute and cumulative effects on basal cortisol levels and repetitive behaviors for adults with ASD, particularly those with higher cortisol levels and rates of behaviors.