Matching Items (7)
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- Creators: Doane, Leah
Description
There is preclinical evidence that the detrimental cognitive effects of hormone loss can be ameliorated by estrogen therapy (Bimonte, Acosta, & Talboom, 2010), however, one of the primary concerns with current hormone therapies is that they are nonselective, leading to increased risk of breast and endometrial cancers as well as heart disease. Thus, in order to achieve a successful and clinically relevant long-term hormone therapy option, it is optimal to find an estrogen therapy regimen that is selective to its target tissue. Recently, phytoestrogens have been found to exert selective, beneficial effects on cognition and brain. For example, genistein and diadzein produce neuroprotective effects in cognitive brain regions (Zhao, Chen, & Diaz Brinton, 2002). The purpose of this study was threefold: 1) to examine the cognitive impact of phytoestrogens in young ovariectomized rats, 2) to replicate the dose effects found in the Luine study (Luine et al., 2006), while controlling for manufacturer differences, and 3) to assess if the rodent diet used in our laboratory has an estrogenic-like cognitive impact.The current findings suggest that, at least for object memory, diets containing varying amounts of phytoestrogens can alter cognition, with diets containing high amounts of phytoestrogens showing potential benefits to this type of memory.
ContributorsWhitton, Elizabeth Nicole (Author) / Bimonte-Nelson, Heather (Thesis director) / Presson, Clark (Committee member) / Baxter, Leslie (Committee member) / Barrett, The Honors College (Contributor) / Department of Psychology (Contributor)
Created2013-05
Description
Motor behavior is prone to variable conditions and deviates further in disorders affecting the nervous system. A combination of environmental and neural factors impacts the amount of uncertainty. Although the influence of these factors on estimating endpoint positions have been examined, the role of limb configuration on endpoint variability has been mostly ignored. Characterizing the influence of arm configuration (i.e. intrinsic factors) would allow greater comprehension of sensorimotor integration and assist in interpreting exaggerated movement variability in patients. In this study, subjects were placed in a 3-D virtual reality environment and were asked to move from a starting position to one of three targets in the frontal plane with and without visual feedback of the moving limb. The alternating of visual feedback during trials increased uncertainty between the planning and execution phases. The starting limb configurations, adducted and abducted, were varied in separate blocks. Arm configurations were setup by rotating along the shoulder-hand axis to maintain endpoint position. The investigation hypothesized: 1) patterns of endpoint variability of movements would be dependent upon the starting arm configuration and 2) any differences observed would be more apparent in conditions that withheld visual feedback. The results indicated that there were differences in endpoint variability between arm configurations in both visual conditions, but differences in variability increased when visual feedback was withheld. Overall this suggests that in the presence of visual feedback, planning of movements in 3D space mostly uses coordinates that are arm configuration independent. On the other hand, without visual feedback, planning of movements in 3D space relies substantially on intrinsic coordinates.
ContributorsRahman, Qasim (Author) / Buneo, Christopher (Thesis director) / Helms Tillery, Stephen (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05
Description
Motor behavior is prone to variable conditions and deviates further in disorders affecting the nervous system. A combination of environmental and neural factors impacts the amount of uncertainty. Although the influence of these factors on estimating endpoint positions have been examined, the role of limb configuration on endpoint variability has been mostly ignored. Characterizing the influence of arm configuration (i.e. intrinsic factors) would allow greater comprehension of sensorimotor integration and assist in interpreting exaggerated movement variability in patients. In this study, subjects were placed in a 3-D virtual reality environment and were asked to move from a starting position to one of three targets in the frontal plane with and without visual feedback of the moving limb. The alternating of visual feedback during trials increased uncertainty between the planning and execution phases. The starting limb configurations, adducted and abducted, were varied in separate blocks. Arm configurations were setup by rotating along the shoulder-hand axis to maintain endpoint position. The investigation hypothesized: 1) patterns of endpoint variability of movements would be dependent upon the starting arm configuration and 2) any differences observed would be more apparent in conditions that withheld visual feedback. The results indicated that there were differences in endpoint variability between arm configurations in both visual conditions, but differences in variability increased when visual feedback was withheld. Overall this suggests that in the presence of visual feedback, planning of movements in 3D space mostly uses coordinates that are arm configuration independent. On the other hand, without visual feedback, planning of movements in 3D space relies substantially on intrinsic coordinates.
ContributorsRahman, Qasim (Author) / Buneo, Christopher (Thesis director) / Helms Tillery, Stephen (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05
Description
Sibling interactions are natural contexts for learning about the appropriate expression of emotions. The emotionally charged nature of sibling interactions creates a convenient context to explore emotional reactivity and regulation. The purpose of this study was to examine the relations among parent-reported sibling relationship quality, observed sibling prosocial and antisocial behaviors displayed when playing a competitive marble game, and children's emotions coded from videotape. The sample consisted of 58 twin children who are currently participating in the longitudinal Arizona Twin Project. Parents completed the Sibling Relationship Questionnaire online at 5 and 8 years. Additionally, a competitive marble game interaction between the siblings took place in the home at 8 years and was videotaped for objective coding of prosocial, antisocial, and control behavior. Facial expressions were also coded from videotape using Emotient FACET software across the marble game interaction. Three mean composites of emotion were created, including positive and negative emotional facial expressions. Results showed that parent reported warmth did not predict the occurrence of positive emotions during the sibling interaction. However, siblings with high conflict showed less fear during the interaction. Parent reports of warmth predicted the extent to which siblings differed on emotion expression, however conflict did not. Parent ratings of conflict and warmth did not predict the extent to which the sibling dyad was emotionally intense. Findings regarding genetic and environmental effects were in line with previous reports of genetic influence on prosocial behavior and negative emotion, and expressions of joy being influenced by the environment. This study investigated noteworthy aspects of the sibling relationship that appear to promote children's adaptive development.
ContributorsGanase, Anaelle Shelina (Co-author) / Oro, Veronica (Co-author) / Roth, Winter (Co-author) / Doane, Leah (Co-author) / Lemery-Chalfant, Kathryn (Co-author, Thesis director) / Miadich, Samantha (Committee member) / Davis, Mary (Committee member) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
The objective of the current study was to examine sleep and academic functioning during middle childhood. More specifically, the twin design was used to determine the heritability of academic competence and sleep. Phenotypic analyses using multi-level mixed model regressions were performed to predict academic functioning from sleep. Lastly, socioeconomic status was tested as a moderator in the associations between sleep and academic functioning. Participants included twins (N = 191 families; Mage = 8.47 years) recruited from Arizona birth records at 12 months of age. Sleep duration, latency, onset, efficiency, variability, and sleep problems were assessed using actigraph watches and the Child Sleep Habits Questionnaire. Academic functioning was assessed using subtests of the Woodcock Johnson Cognitive Test of Achievement-IV (picture vocabulary, passage comprehension, and applied problems) and the MacArthur Health and Behavior Questionnaire. As determined by twin intraclass correlations, the heritability of academic competence ranged from 51-76%. Sleep heritability ranged from 14-80%. In addition, phenotypic analyses only showed a significant association between sleep latency and WJ picture vocabulary scores. More specifically, sleep latency was negatively associated with the picture vocabulary subtest. Additional models were run to examine if any interactive effects were present between early SES and the various sleep parameters. Several significant associations were observed with applied problems scores and parent-reported academic competence. Specifically, for children of low SES, a significant positive association was observed for sleep duration and WJ applied problems scores, as well as for sleep efficiency and WJ applied problems scores. No significant associations were observed for sleep efficiency and HBQ scores with children of any SES. Also, no significant relationships were observed with children of high SES for any of the academic measures.
ContributorsVakulskas, Emily (Author) / Doane, Leah (Thesis director) / Lemery-Chalfant, Kathryn (Committee member) / Breitenstein, Reagan (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
This study examined the cross-sectional and longitudinal associations among diurnal cortisol rhythms and sleeping patterns in adolescents. 79 participants completed the study over three days during the spring semester of their senior year in high school, and 76 of these subjects participated again over three days during the fall semester of their freshman year in college. They completed daily saliva samples and diary entries, while wearing an actigraph to obtain objective measurements of sleep duration and efficiency. Cross-sectionally, longer sleep duration was associated with a lower cortisol awakening response, a smaller area under the cortisol curve, and a steeper cortisol slope. Longitudinally, there was no significant relationship between sleep duration and these cortisol parameters. Moreover, sleep efficiency was not associated with cortisol parameters cross-sectionally nor longitudinally. Results suggest associations between concurrent sleep duration and cortisol patterns, and may have significant impact on understanding adolescents' physiological response to stress.
ContributorsLathrop, Devon Olivia (Author) / Doane, Leah (Thesis director) / Orchinik, Miles (Committee member) / Zeiders, Katherine (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2013-05
Description
This study sought to determine if perceived neighborhood danger impacted children's sleep. The current study asks: how does perceived neighborhood danger impact children’s sleep both quantity and quality (duration and efficiency), could children’s physical activity mediate these associations, and how do genetic and environmental factors play into these relationships? Questionnaires, biological measurements, and actigraphy watch data were collected from 709 8-year-old Arizonan twins and their parents in order to calculate neighborhood safety, sedentary physical activity, moderate to vigorous physical activity, sleep duration, and sleep efficiency as well as covariates. It was concluded that perceived neighborhood danger does not directly impact children’s sleep duration and efficiency, children’s physical activity does not mediate the relation of perceived neighborhood danger and children’s sleep, but rather, perceived neighborhood danger indirectly impacts children’s sleep duration and efficiency through moderate to vigorous activity, and finally, that both sedentary and moderate to vigorous activity are heavily influenced by genetics.
ContributorsFlake, Ashton (Author) / Lemery-Chalfant, Kathryn (Thesis director) / Corbin, William (Committee member) / Doane, Leah (Committee member) / Barrett, The Honors College (Contributor) / Department of Psychology (Contributor) / The Sidney Poitier New American Film School (Contributor)
Created2021-12