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- Creators: Barrett, The Honors College
- Creators: Bimonte-Nelson, Heather A.
Description
Chronic restraint stress impairs hippocampal-mediated spatial learning and memory, which improves following a post-stress recovery period. Here, we investigated whether brain derived neurotrophic factor (BDNF), a protein important for hippocampal function, would alter the recovery from chronic stress-induced spatial memory deficits. Adult male Sprague-Dawley rats were infused into the hippocampus with adeno- associated viral vectors containing the coding sequence for short interfering (si)RNA directed against BDNF or a scrambled sequence (Scr), with both containing the coding information for green fluorescent protein to aid in anatomical localization. Rats were then chronically restrained (wire mesh, 6h/d/21d) and assessed for spatial learning and memory using a radial arm water maze (RAWM) either immediately after stressor cessation (Str-Imm) or following a 21-day post-stress recovery period (Str-Rec). All groups learned the RAWM task similarly, but differed on the memory retention trial. Rats in the Str-Imm group, regardless of viral vector contents, committed more errors in the spatial reference memory domain than did non-stressed controls. Importantly, the typical improvement in spatial memory following recovery from chronic stress was blocked with the siRNA against BDNF, as Str-Rec-siRNA performed worse on the RAWM compared to the non-stressed controls or Str-Rec-Scr. These effects were specific for the reference memory domain as repeated entry errors that reflect spatial working memory were unaffected by stress condition or viral vector contents. These results demonstrate that hippocampal BDNF is necessary for the recovery from stress-induced hippocampal dependent spatial memory deficits in the reference memory domain.
ContributorsOrtiz, J. Bryce (Author) / Conrad, Cheryl D. (Thesis advisor) / Olive, M. Foster (Committee member) / Taylor, Sara (Committee member) / Bimonte-Nelson, Heather A. (Committee member) / Arizona State University (Publisher)
Created2013
Description
Cognitive function declines with normal age and disease states, such as Alzheimer's disease (AD). Loss of ovarian hormones at menopause has been shown to exacerbate age-related memory decline and may be related to the increased risk of AD in women versus men. Some studies show that hormone therapy (HT) can have beneficial effects on cognition in normal aging and AD, but increasing evidence suggests that the most commonly used HT formulation is not ideal. Work in this dissertation used the surgically menopausal rat to evaluate the cognitive effects and mechanisms of progestogens proscribed to women. I also translated these questions to the clinic, evaluating whether history of HT use impacts hippocampal and entorhinal cortex volumes assessed via imaging, and cognition, in menopausal women. Further, this dissertation investigates how sex impacts responsiveness to dietary interventions in a mouse model of AD. Results indicate that the most commonly used progestogen component of HT, medroxyprogesterone acetate (MPA), impairs cognition in the middle-aged and aged surgically menopausal rat. Further, MPA is the sole hormone component of the contraceptive Depo Provera, and my research indicates that MPA administered to young-adult rats leads to long lasting cognitive impairments, evident at middle age. Natural progesterone has been gaining increasing popularity as an alternate option to MPA for HT; however, my findings suggest that progesterone also impairs cognition in the middle-aged and aged surgically menopausal rat, and that the mechanism may be through increased GABAergic activation. This dissertation identified two less commonly used progestogens, norethindrone acetate and levonorgestrel, as potential HTs that could improve cognition in the surgically menopausal rat. Parameters guiding divergent effects on cognition were discovered. In women, prior HT use was associated with larger hippocampal and entorhinal cortex volumes, as well as a modest verbal memory enhancement. Finally, in a model of AD, sex impacts responsiveness to a dietary cognitive intervention, with benefits seen in male, but not female, transgenic mice. These findings have clinical implications, especially since women are at higher risk for AD diagnosis. Together, it is my hope that this information adds to the overarching goal of optimizing cognitive aging in women.
ContributorsBraden, Brittany Blair (Author) / Bimonte-Nelson, Heather A. (Thesis advisor) / Neisewander, Janet L (Committee member) / Conrad, Cheryl D. (Committee member) / Baxter, Leslie C (Committee member) / Arizona State University (Publisher)
Created2012
Description
After natural menopause in women, androstenedione becomes the primary hormone secreted by the residual follicle deplete ovaries. Two independent studies, in rodents that had undergone ovarian follicular depletion, found that higher serum androstenedione levels correlated with increased working memory errors. This led to the hypothesis that androstenedione impairs memory. The current study directly tested this hypothesis, examining the cognitive effects of androstenedione administration in a rodent model. Middle-aged ovariectomized rats received vehicle or one of two doses of androstenedione (4 or 8 mg/kg daily). Rats were tested on a spatial working and reference memory maze battery including the water radial arm maze, Morris maze, and delay-match-to-sample task. Results showed that androstenedione at the highest dose impaired reference memory and working memory, including ability to maintain performance as memory demand was elevated. The latter was true for both high temporal demand memory retention of one item of spatial information, as well as the ability to handle multiple items of spatial working memory information. Glutamic acid decarboxylase (GAD) levels were measured in multiple brain regions to determine whether the gamma-aminobutyric acid (GABA) system mediates androstenedione's cognitive impairments. Results showed that higher entorhinal cortex GAD levels were correlated with poorer Morris maze performance, regardless of androstenedione treatment. These findings suggest that androstenedione, the main hormone produced by the follicle deplete ovary, is detrimental to spatial learning, reference memory, and working memory, and that spatial reference memory performance might be related to the GABAergic system.
ContributorsCamp, Bryan Walter (Author) / Bimonte-Nelson, Heather A. (Thesis advisor) / Olive, Michael F (Committee member) / Conrad, Cheryl D. (Committee member) / Arizona State University (Publisher)
Created2012
Description
Ethinyl estradiol, (EE) a synthetic, orally bio-available estrogen, is the most commonly prescribed form of estrogen in oral contraceptives (Shively, C., 1998), and is found in at least 30 different contraceptive formulations currently prescribed to women (Curtis et al., 2005). EE is also used in hormone therapies prescribed to menopausal women, such as FemhrtTM (Simon et al., 2003). Thus, EE is prescribed clinically to women at ages ranging from puberty through reproductive senescence. Here, in two separate studies, the cognitive effects of cyclic or tonic EE administration following ovariectomy (Ovx) were evaluated in young, female rats. Study I assessed the cognitive effects of low and high doses of EE, delivered tonically via a subcutaneous osmotic pump. Study II evaluated the cognitive effects of low, medium, and high doses of EE administered via a daily subcutaneous injection. For these studies, the low and medium doses correspond to the range of doses currently used in clinical formulations, and the high dose corresponds to the range of doses prescribed to a generation of women between 1960 and 1970, when oral contraceptives first became available. For each study, cognition was evaluated with a battery of maze tasks tapping several domains of spatial learning and memory. At the highest dose, EE treatment impaired multiple domains of spatial memory relative to vehicle treatment, regardless of administration method. When given cyclically at the low and medium doses, EE did not impact working memory, but transiently impaired reference memory during the learning phase of testing. Of the doses and regimens tested here, only EE at the highest dose impaired several domains of memory; this was seen for both cyclic and tonic regimens. Cyclic and tonic delivery of low EE, a dose that corresponds to doses used in the clinic today, resulted in transient and null impairments, respectively, on cognition.
ContributorsMennenga, Sarah E (Author) / Bimonte-Nelson, Heather A. (Thesis advisor) / Baxter, Leslie C. (Committee member) / Olive, Michael F. (Committee member) / Arizona State University (Publisher)
Created2012
Description
I am double majoring in Film & Media Production and Geography, and whenever I tell anyone that their first reaction is one of polite incredulity. The two disciplines seem so far from each other that there doesn't seem to be any possible way of combining them. With this project, I wanted to incorporate these two very different fields into one meaningful product. Using film as a medium, I explored how impactful a geographical location can truly be on someone. When we think about our pasts, we often focus on the people and events, losing sight of the physical location where these memories take place. Life in a Museum attempts to shine a light on this forgotten aspect of memory. I moved to Prescott, Arizona when I was 11 and moved away when I was 18, living there for only 7 years. Yet as time passes, I am starting to realize how impactful Prescott has been on me. For my Honors Creative Project, I created a video essay in an attempt to "map" my relationship with Prescott and how it has changed over time. Incorporating digital video, Google SketchUp Animations and historical photographs, Life in a Museum acts as collage that attempts to mimic the tangential aspects of memory. The film addresses my upbringing in Prescott, the town's intense pride for its history, and how living there has affected my own perception of time, memory, death and the future. Link to video: https://vimeo.com/126633587
ContributorsJones, Zachary Loren (Author) / Larson, Elizabeth (Thesis director) / Kitson, Jennifer (Committee member) / Barrett, The Honors College (Contributor) / School of Geographical Sciences and Urban Planning (Contributor) / School of Film, Dance and Theatre (Contributor)
Created2015-05
Description
A longing to revisit the people, places, and moments of my past has followed me for years, sometimes affecting me to the extent that the past seems to intrude on my present. In this piece, I wish to turn a critical eye on these feelings of nostalgia and examine how strong emotion can emerge from nothing more than fractured, faded memories. Using footage of moments I had recorded over six months of living in Europe, I seek to sculpt these images from my past into a form that rejects the daze of nostalgia for the fragmented truth of memory. My background is in more traditional narrative filmmaking, and so I was excited to work in this experimental three-screen format, in which I could explore the concept of memory in a manner that felt truer to how I actually experience it. I tested various combinations of imagery in my videos to build the progression of the piece, which I hoped would play out in an associational style that mimicked the process of my own memory. I hope that this will cause people to walk away from the piece thinking about how memory can fuel emotion and even to investigate their own relationship to the past.
ContributorsPowell, Matthew Rhys (Author) / Bradley, Christopher (Thesis director) / Brye, Anne (Committee member) / Barrett, The Honors College (Contributor) / School of International Letters and Cultures (Contributor) / School of Film, Dance and Theatre (Contributor)
Created2015-05
Description
Memory Wipe is a 22 minute, video art piece that utilizes home movie footage filmed on VHS and 8mm, as well as television and cartoon ephemera, to explore the way in which personal memory is constructed and altered through the process of recording and viewing. Three recent events in my life inspired work: the discovery of a box containing my favorite childhood media, the revelation that I am the last male of my family, and the impending sale of my family's farmland. My mother never used a video camera, insisting that her childhood was lost in footage filmed but never watched. It should also be noted that not once do I appear in this piece; therefore, I decided to extract myself from the narrative. Rather than simply guide the audience along with anecdotes from my life, I instead invite viewers to draw their own meanings and create their own nostalgias from the piece. Originally, Memory Wipe was to be accompanied by live narration, but all things considered, I thought I would let it speak for itself. Video link: https://www.youtube.com/watch?v=-E42a6Koma4
ContributorsMcDougall, Clayton Ross (Author) / Magenta, Muriel (Thesis director) / Brye, Anne (Committee member) / Barrett, The Honors College (Contributor) / School of Film, Dance and Theatre (Contributor) / School of Historical, Philosophical and Religious Studies (Contributor)
Created2015-05
Description
Since Dylan Roof, a white supremacist, shot and killed nine members of a black church in Charleston on June 17, 2015, Confederate symbols have stood at the center of much controversy across the United States. Although the Confederate battle flag remains the most obvious example, the debate took a particular form in Tennessee, centering on the image of General Nathan Bedford Forrest. Born in 1822 to a poor family, he left school early to work. Although his work in the slave trade made him a millionaire, his later participation in the massacre of over 300 black soldiers at Fort Pillow in 1864 during the Civil War and association with the Ku Klux Klan cemented his reputation as a violent racist. Yet, many white Tennesseans praised him as a hero and memorialized him. This thesis examines Nathan Bedford Forrest State Park in Benton County and Forrest Park, now Health Sciences Park, in Memphis to examine what characteristics denote a controversial memorial. Specifically, I focus on the physical form, the location, and the demographics of the area, investigating how these components work together to give rise to controversy or acceptance of the memorial's image. Physical representations greatly impact the ideas associated with the memorial while racial demographics affect whether or not Forrest's representation as a hero speaks true to modern interpretations and opinions.
ContributorsFish, Caroline Rose (Author) / Longley, Rodney (Thesis director) / Suk, Mina (Committee member) / School of Historical, Philosophical and Religious Studies (Contributor) / School of Politics and Global Studies (Contributor) / School of International Letters and Cultures (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
This study was conducted in order to create a brief task that more efficiently studies the memory of young and old dogs compared to previous dog radial arm mazes. The hypotheses were older dogs would perform worse than younger dogs, brief tasks with longer delays and the presence of an occluder would produce worse results, and the brief task with the longest delay period without an occluder would be most correlated to the radial arm maze. 45 dogs were tested from a previous sample that had participated in a radial arm maze experiment. The dogs were tested in their owner's homes and watched the researcher place a treat behind one of two boxes. Dogs then waited during different delay periods, of 15, 30, or 45 seconds, and with or without an occluder, which was a curtain. Then, the dog was released to see if it could still remember which box the treat was behind. The results supported all the hypotheses, except the 45-second brief task with an occluder was most correlated the radial arm maze. Additionally, the dogs that had to be excluded from the radial arm maze still had a similar range of results on the brief tasks as dogs that were able to complete the radial arm maze. These results confirm the radial arm maze is very difficult and strenuous on dogs, but the brief task is correlated and probably much more effective at studying memory without these issues. This study can help researchers perfect this simple task in order to study many dogs much quicker and collect more information on dogs' memory. Future studies could overcome limitations including dogs that were not motivated by treats or that were too old to stand up. Specific breeds could be tested or longitudinal studies could be conducted to find differences in memory over time. In the future, this can hopefully relate to human cognitive decline knowledge, as dogs show similar cognitive decline to humans, and help find treatments for cognitive diseases.
ContributorsGlomski, Marissa (Author) / Wynne, Clive (Thesis director) / Presson, Clive (Committee member) / Brewer, Gene (Committee member) / Department of Psychology (Contributor) / School of Social and Behavioral Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2015-12
Description
‘why we bend' a Bachelor of Fine Arts honors thesis exhibition by Ximenna Hofsetz and Tiernan Warner brings together installation, digital, sculptural, and printed artwork. The main focus concerns memory; and its vague, formless, and hazy nature. The work also examines what would happen if cognitive space could be physically mapped? What would it look like in sculptural form? Memory erodes and distorts with time. We influence our memories as much as they affect us. Thus, just as relationships are ever-changing, and our memories of those we interact with constantly shifting, our relationships with our own memories are malleable and evolve through time. This transient nature of memory is depicted in the various stylistic means of this exhibition by referencing time and space as well as personal memories and ephemera in both concrete and abstract ways. ‘why we bend’ implements a variety of multimedia techniques to examine recollection and its hold on us.
ContributorsHofsetz, Ximenna Cedella (Author) / Gutierrez, Rogelio (Thesis director) / Hood, Mary (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor) / School of Art (Contributor)
Created2014-12