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This research is focused on two separate but related topics. The first uses an electroencephalographic (EEG) brain-computer interface (BCI) to explore the phenomenon of motor learning transfer. The second takes a closer look at the EEG-BCI itself and tests an alternate way of mapping EEG signals into machine commands. We test whether motor learning transfer is more related to use of shared neural structures between imagery and motor execution or to more generalized cognitive factors. Using an EEG-BCI, we train one group of participants to control the movements of a cursor using embodied motor imagery. A second group is trained to control the cursor using abstract motor imagery. A third control group practices moving the cursor using an arm and finger on a touch screen. We hypothesized that if motor learning transfer is related to the use of shared neural structures then the embodied motor imagery group would show more learning transfer than the abstract imaging group. If, on the other hand, motor learning transfer results from more general cognitive processes, then the abstract motor imagery group should also demonstrate motor learning transfer to the manual performance of the same task. Our findings support that motor learning transfer is due to the use of shared neural structures between imaging and motor execution of a task. The abstract group showed no motor learning transfer despite being better at EEG-BCI control than the embodied group. The fact that more participants were able to learn EEG-BCI control using abstract imagery suggests that abstract imagery may be more suitable for EEG-BCIs for some disabilities, while embodied imagery may be more suitable for others. In Part 2, EEG data collected in the above experiment was used to train an artificial neural network (ANN) to map EEG signals to machine commands. We found that our open-source ANN using spectrograms generated from SFFTs is fundamentally different and in some ways superior to Emotiv's proprietary method. Our use of novel combinations of existing technologies along with abstract and embodied imagery facilitates adaptive customization of EEG-BCI control to meet needs of individual users.
Contributorsda Silva, Flavio J. K (Author) / Mcbeath, Michael K (Thesis advisor) / Helms Tillery, Stephen (Committee member) / Presson, Clark (Committee member) / Sugar, Thomas (Committee member) / Arizona State University (Publisher)
Created2013
Description
Although research has documented robust prospective relationships between externalizing symptomatology and subsequent binge drinking among adolescents, the extent to which internalizing symptoms increase risk for drinking remains controversial. In particular, the role of anxiety as a predictor of binge drinking remains unclear. Recent evidence suggests that one possible reason for these mixed findings is that separate dimensions of anxiety may differentially confer risk for alcohol use. The present study tested two dimensions of anxiety - worry and physiological anxiety -- as predictors of binge drinking in a longitudinal study of juvenile delinquents. Overall, results indicate that worry and physiological anxiety showed differential relations with drinking behavior. In general, worry was protective against alcohol use, whereas physiological anxiety conferred risk for binge drinking, but both effects were conditional on levels of offending. Implications for future research examining the role of anxiety in predicting drinking behavior among youth are discussed.
ContributorsNichter, Brandon (Author) / Chassin, Laurie (Thesis advisor) / Barrera, Manuel (Committee member) / Presson, Clark (Committee member) / Arizona State University (Publisher)
Created2014
Description
Fibromyalgia (FM) is a chronic musculoskeletal disorder characterized by widespread pain, fatigue, and a variety of other comorbid physiological and psychological characteristics, including a deficit of positive affect. Recently, the focus of research on the pathophysiology of FM has considered the role of a number of genomic variants. In the current manuscript, case-control analyses did not support the hypothesis that FM patients would differ from other chronic pain groups in catechol-O-methyltransferase (COMT) and mu-opioid receptor (OPRM1) genotype. However, evidence is provided in support of the hypothesis that functional single nucleotide polymorphisms on the COMT and OPRM1 genes would be associated with risk and resilience, respectively, in a dual processing model of pain-related positive affective regulation in FM. Forty-six female patients with a physician-confirmed diagnosis of FM completed an electronic diary that included once-daily assessments of positive affect and soft tissue pain. Multilevel modeling yielded a significant gene X environment interaction, such that individuals with met/met genotype on COMT experienced a greater decline in positive affect as daily pain increased than did either val/met or val/val individuals. A gene X environment interaction for OPRM1 also emerged, indicating that individuals with at least one asp allele were more resilient to elevations in daily pain than those homozygous for the asn allele. In sum, the findings offer researchers ample reason to further investigate the contribution of the catecholamine and opioid systems, and their associated genomic variants, to the still poorly understood experience of FM.
ContributorsFinan, Patrick Hamilton (Author) / Zautra, Alex (Thesis advisor) / Davis, Mary (Committee member) / Lemery-Chalfant, Kathryn (Committee member) / Presson, Clark (Committee member) / Arizona State University (Publisher)
Created2011
Description
When people pick up the phone to call a telephone quitline, they are taking an important step towards changing their smoking behavior. The current study investigated the role of a critical cognition in the cessation process--self-efficacy. Self-efficacy is thought to be influential in behavior change processes including those involved in the challenging process of stopping tobacco use. By applying basic principles of self-efficacy theory to smokers utilizing a telephone quitline, this study advanced our understanding of the nature of self-efficacy in a "real-world" cessation setting. Participants received between one and four intervention calls aimed at supporting them through their quit attempt. Concurrent with the initiation of this study, three items (confidence, stress, and urges) were added to the standard telephone protocol and assessed at each call. Two principal sets of hypotheses were tested using a combination of ANCOVAs and multiple regression analyses. The first set of hypotheses explored how self-efficacy and changes in self-efficacy within individuals were associated with cessation outcomes. Most research has found a positive linear relation between self-efficacy and quit outcomes, but this study tested the possibility that excessively high self-efficacy may actually reflect an overconfidence bias, and in some cases be negatively related to cessation outcomes. The second set of hypotheses addressed several smoking-related factors expected to affect self-efficacy. As predicted, higher baseline self-efficacy and increases in self-efficacy were associated with higher rates of quitting. However, contrary to predictions, there was no evidence that overconfidence led to diminished cessation success. Finally, as predicted, shorter duration of quit attempts, shorter time to relapse, and stronger urges all were associated with lower self-efficacy. In conclusion, understanding how self-efficacy and changes in self-efficacy affect and are affected by cessation outcomes is useful for informing both future research and current quitline intervention procedures.
ContributorsGoesling, Jenna (Author) / Barrera, Manuel (Thesis advisor) / Shiota, Lani (Committee member) / Enders, Craig (Committee member) / Presson, Clark (Committee member) / Arizona State University (Publisher)
Created2011
Description
Systemic lupus erytematosus (SLE) is an autoimmune disease where the immune system is reactive to self antigens resulting in manifestations like glomerulonephritis and arthritis. The immune system also affects the central nervous system (known as CNS-SLE) leading to neuropsychiatric manifestations such as depression, cognitive impairment, psychosis and seizures. A subset of pathogenic brain-reactive autoantibodies (BRAA) is hypothesized to bind to integral membrane brain proteins, affecting their function, leading to CNS-SLE. I have tested this BRAA hypothesis, using our lupus-mouse model the MRL/lpr mice, and have found it to be a reasonable explanation for some of the manifestations of CNS-SLE. Even when the MRL/lpr had a reduced autoimmune phenotype, their low BRAA sera levels correlated with CNS involvement. The correlation existed between BRAA levels to integral membrane protein and depressive-like behavior. These results were the first to show a correlation between behavioral changes and BRAA levels from brain membrane antigen as oppose to cultured neuronal cells. More accurate means of predicting and diagnosing lupus and CNS-SLE is necessary. Using microarray technology I was able to determine peptide sets that could be predictive and diagnostic of lupus and each specific CNS manifestation. To knowledge no test currently exists that can effectively diagnose lupus and distinguish between each CNS manifestations. Using the peptide sets, I was able to determine possible natural protein biomarkers for each set as well as for five monoclonal BRAA from one MRL/lpr. These biomarkers can provide specific targets for therapy depending on the manifestation. It was necessary to investigate how these BRAA enter the brain. I hypothesized that substance P plays a role in altering the blood-brain barrier (BBB) allowing these BRAA to enter and affect brain function, when bound to its neurokinin-1 receptor (NK-1R). Western blotting results revealed an increase in the levels of NK-1R in the brain of the MRL/lpr compared to the MRL/mp. These MRL/lpr with increased levels of both NK-1R and BRAA displayed CNS dysfunction. Together, these results demonstrate that NK-1R may play a role in CNS manifestations. Overall, the research conducted here, add to the role that BRAA are playing in CNS-lupus.
ContributorsWilliams, Stephanie (Author) / Hoffman, Steven A (Thesis advisor) / Conrad, Cheryl (Committee member) / Chen, Julian (Committee member) / Orchinik, Miles (Committee member) / Arizona State University (Publisher)
Created2011
Description
Food is an essential driver of animal behavior. For social organisms, the acquisition of food guides interactions with the environment and with group-mates. Studies have focused on how social individuals find and choose food sources, and share both food and information with group-mates. However, it is often not clear how experiences throughout an individual's life influence such interactions. The core question of this thesis is how individuals’ experience contributes to within-caste behavioral variation in a social group. I investigate the effects of individual history, including physical injury and food-related experience, on individuals' social food sharing behavior, responses to food-related stimuli, and the associated neural biogenic amine signaling pathways. I use the eusocial honey bee (Apis mellifera) system, one in which individuals exhibit a high degree of plasticity in responses to environmental stimuli and there is a richness of communicatory pathways for food-related information. Foraging exposes honey bees to aversive experiences such as predation, con-specific competition, and environmental toxins. I show that foraging experience changes individuals' response thresholds to sucrose, a main component of adults’ diets, depending on whether foraging conditions are benign or aversive. Bodily injury is demonstrated to reduce individuals' appetitive responses to new, potentially food-predictive odors. Aversive conditions also impact an individual's social food sharing behavior; mouth-to-mouse trophallaxis with particular groupmates is modulated by aversive foraging conditions both for foragers who directly experienced these conditions and non-foragers who were influenced via social contact with foragers. Although the mechanisms underlying these behavioral changes have yet to be resolved, my results implicate biogenic amine signaling pathways as a potential component. Serotonin and octopamine concentrations are shown to undergo long-term change due to distinct foraging experiences. My work serves to highlight the malleability of a social individual's food-related behavior, suggesting that environmental conditions shape how individuals respond to food and share information with group-mates. This thesis contributes to a deeper understanding of inter-individual variation in animal behavior.
ContributorsFinkelstein, Abigail (Author) / Amdam, Gro V (Thesis advisor) / Conrad, Cheryl (Committee member) / Smith, Brian (Committee member) / Neisewander, Janet (Committee member) / Bimonte-Nelson, Heather A. (Committee member) / Arizona State University (Publisher)
Created2017
Description
Body size plays a pervasive role in determining physiological and behavioral performance across animals. It is generally thought that smaller animals are limited in performance measures compared to larger animals; yet, the vast majority of animals on earth are small and evolutionary trends like miniaturization occur in every animal clade. Therefore, there must be some evolutionary advantages to being small and/or compensatory mechanisms that allow small animals to compete with larger species. In this dissertation I specifically explore the scaling of flight performance (flight metabolic rate, wing beat frequency, load-carrying capacity) and learning behaviors (visual differentiation visual Y-maze learning) across stingless bee species that vary by three orders of magnitude in body size. I also test whether eye morphology and calculated visual acuity match visual differentiation and learning abilities using honeybees and stingless bees. In order to determine what morphological and physiological factors contribute to scaling of these performance parameters I measure the scaling of head, thorax, and abdomen mass, wing size, brain size, and eye size. I find that small stingless bee species are not limited in visual learning compared to larger species, and even have some energetic advantages in flight. These insights are essential to understanding how small size evolved repeatedly in all animal clades and why it persists. Finally, I test flight performance across stingless bee species while varying temperature in accordance with thermal changes that are predicted with climate change. I find that thermal performance curves varied greatly among species, that smaller species conform closely to air temperature, and that larger bees may be better equipped to cope with rising temperatures due to more frequent exposure to high temperatures. This information may help us predict whether small or large species might fare better in future thermal climate conditions, and which body-size related traits might be expected to evolve.
ContributorsDuell, Meghan (Author) / Harrison, Jon F. (Thesis advisor) / Smith, Brian H. (Thesis advisor) / Rutowski, Ronald (Committee member) / Wcislo, William (Committee member) / Conrad, Cheryl (Committee member) / Arizona State University (Publisher)
Created2018
Description
Estrogen-containing hormone therapy (HT) is approved for treatment of symptoms associated with menopause by the Food and Drug Administration. A common estrogen used in HT is 17β-estradiol (E2). Rodent models of menopause, and some clinical work as well, suggest a cognitively-beneficial role of E2. However, as of the 2017 statement released by the North American Menopause Society, HT is not currently advised for use as cognitive therapy in healthy, menopausal women, given that the data so far from existing clinical studies are not yet definitive. Indeed, the delivery of E2 treatment can be optimized to yield more consistent results on cognitive function, particularly considering that exogenously administered E2 gets rapidly metabolized and cleared from the body. Further, E2-containing HT must include a progestogen if prescribed to women with a uterus to oppose its undesired uterine stimulating effects, such as increased endometrial hyperplasia and cancer risks. Studies have shown that the addition of a progestogen to E2 treatment can attenuate the effects of E2 on cognition and brain variables associated with cognitive function. Thus, a brain-specific delivery platform of E2 treatment that would minimize the hormone’s effects in the periphery while maintaining the beneficial cognitive effects is desirable. To achieve this goal, my dissertation work bridged two distinct scientific fields – behavioral neuroendocrinology and polymeric drug delivery – with the overarching aim of targeting the delivery of E2 to the brain to achieve maximal cognitively-beneficial effects with minimal undesired uterine stimulation. This aim was addressed via three distinct delivery strategies: 1) combining E2 with a cognitively-beneficial progestogen, 2) encapsulating E2 in polymeric nanoparticles, and 3) solubilizing E2 using cyclodextrins for intranasal administration. Findings revealed that although all E2-containing treatments increased uterine horn weights, a marker of uterine stimulation, in middle-aged ovariectomized rats, some E2 treatment formulations yielded memory improvements, others were neutral in their effects on memory, and some impaired memory. Together, data from this dissertation set the stage for targeted E2 delivery research to optimize the cognitive therapeutic effects of E2 in the context of menopause while minimizing peripheral burden, leading to translationally relevant clinical implications for women’s health.
ContributorsPrakapenka, Alesia (Author) / Bimonte-Nelson, Heather A. (Thesis advisor) / Conrad, Cheryl (Committee member) / Stabenfeldt, Sarah (Committee member) / Sirianni, Rachael (Committee member) / Arizona State University (Publisher)
Created2018
Description
The current study investigated whether intermittent restraint stress (IRS) would impair fear extinction learning and lead to increased anxiety and depressive- like behaviors and then be attenuated when IRS ends and a post- stress rest period ensues for 6 weeks. Young adult, male Sprague Dawley rats underwent restraint stress using wire mesh (6hr/daily) for five days with two days off before restraint resumed for three weeks for a total of 23 restraint days. The groups consisted of control (CON) with no restraint other than food and water restriction yoked to the restrained groups, stress immediate (STR-IMM), which were restrained then fear conditioned soon after the end of the IRS paradigm, and stress given a rest for 6 weeks before fear conditioning commenced (STR-R6). Rats were fear conditioned by pairing a 20 second tone with a footshock, then given extinction training for two days (15 tone only on each day). On the first day of extinction, all groups discriminated well on the first trial, but then as trials progressed, STR-R6 discriminated between tone and context less than did CON. On the second day of extinction, STR- IMM froze more to context in the earlier trials than compared to STR-R6 and CON. As trials progressed STR-IMM and STR-R6 froze more to context than compared to CON. Together, CON discriminated between tone and context better than did STR-IMM and STR-R6. Sucrose preference, novelty suppressed feeding, and elevated plus maze was performed after fear extinction was completed. No statistical differences were observed among groups for sucrose preference or novelty suppressed feeding. For the elevated plus maze, STR-IMM entered the open arms and the sum of both open and closed arms fewer than did STR- R6 and CON. We interpret the findings to suggest that the stress groups displayed increased hypervigilance and anxiety with STR-R6 exhibiting a unique phenotype than that of STR-IMM and CON.
ContributorsShah, Vrishti Bimal (Author) / Conrad, Cheryl (Thesis director) / Newbern, Jason (Committee member) / Judd, Jessica (Committee member) / School of Life Sciences (Contributor) / Sanford School of Social and Family Dynamics (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
This purpose of this thesis study was to examine variables of the "War on Cancer" frame, loss-gain prime, and patient gender on treatment decision for advanced cancer patients. A total of 291 participants (141 females) participated in an online survey experiment and were randomly assigned to one of eight possible conditions, each of which were comprised of a combination of one of two levels for three total independent variables: war frame ("War on Cancer" frame or neutral frame), loss-gain prime (loss prime or gain prime), and patient gender (female or male). Each of the three variables were operationalized to determine whether or not the exposure to the war on cancer paradigm, loss-frame language, or male patient gender would increase the likelihood of a participant choosing a more aggressive cancer treatment. Participants read a patient scenario and were asked to respond to questions related to motivating factors. Participants were then asked to report preference for one of two treatment decisions. Participants were then asked to provide brief demographic information in addition to responding to questions about military history, war attitudes, and cancer history. The aforementioned manipulations sought to determine whether exposure to various factors would make a substantive difference in final treatment decision. Contrary to the predicted results, participants in the war frame condition (M = 3.85, SD = 1.48) were more likely to choose the pursuit of palliative care (as opposed to aggressive treatment) than participants in the neutral frame condition (M = 3.54, SD = 1.23). Ultimately, these significant findings suggest that there is practical information to be gained from treatment presentation manipulations. By arming healthcare providers with a more pointed understanding of the nuances of treatment presentation, we can hope to empower patients, their loved ones, and healthcare providers entrenched in the world of cancer treatment.
ContributorsKnowles, Madelyn Ann (Author) / Kwan, Virginia S. Y. (Thesis director) / Presson, Clark (Committee member) / Salamone, Damien (Committee member) / Department of Psychology (Contributor) / School of Human Evolution and Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05