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ASU Electronic Theses and Dissertations


This collection includes most of the ASU Theses and Dissertations from 2011 to present. ASU Theses and Dissertations are available in downloadable PDF format; however, a small percentage of items are under embargo. Information about the dissertations/theses includes degree information, committee members, an abstract, supporting data or media.

In addition to the electronic theses found in the ASU Digital Repository, ASU Theses and Dissertations can be found in the ASU Library Catalog.

Dissertations and Theses granted by Arizona State University are archived and made available through a joint effort of the ASU Graduate College and the ASU Libraries. For more information or questions about this collection contact or visit the Digital Repository ETD Library Guide or contact the ASU Graduate College at gradformat@asu.edu.


Resource Type
Subject
Date Range
2011 2019


The goal of this thesis is to test whether Alzheimer's disease (AD) is associated with distinctive humoral immune changes that can be detected in plasma and tracked across time. This is relevant because AD is the principal cause of dementia, and yet, no specific diagnostic tests are universally employed in clinical practice to predict, diagnose or monitor disease progression. In particular, I describe herein a proteomic platform developed at the Center for Innovations in Medicine (CIM) consisting of a slide with 10.000 random-sequence peptides printed on its surface, which is used as the solid phase of an immunoassay where antibodies …

Contributors
Restrepo Jimenez, Lucas, Johnston, Stephen A, Chang, Yung, et al.
Created Date
2011

An accurate sense of upper limb position is crucial to reaching movements where sensory information about upper limb position and target location is combined to specify critical features of the movement plan. This dissertation was dedicated to studying the mechanisms of how the brain estimates the limb position in space and the consequences of misestimation of limb position on movements. Two independent but related studies were performed. The first involved characterizing the neural mechanisms of limb position estimation in the non-human primate brain. Single unit recordings were obtained in area 5 of the posterior parietal cortex in order to examine …

Contributors
Shi, Ying, Buneo, Christopher A, Helms Tillery, Stephen, et al.
Created Date
2011

Alzheimer's Disease (AD) is a debilitating neurodegenerative disease. The disease leads to dementia and loss of cognitive functions and affects about 4.5 million people in the United States. It is the 7th leading cause of death and is a huge financial burden on the healthcare industry. There are no means of diagnosing the disease before neurodegeneration is significant and sadly there is no cure that controls its progression. The protein beta-amyloid or Aâ plays an important role in the progression of the disease. It is formed from the cleavage of the Amyloid Precursor Protein by two enzymes - â and …

Contributors
Boddapati, Shanta, Sierks, Michael, Arizona State University
Created Date
2011

Neurostimulation methods currently include deep brain stimulation (DBS), optogenetic, transcranial direct-current stimulation (tDCS), and transcranial magnetic stimulation (TMS). TMS and tDCS are noninvasive techniques whereas DBS and optogenetic require surgical implantation of electrodes or light emitting devices. All approaches, except for optogenetic, have been implemented in clinical settings because they have demonstrated therapeutic utility and clinical efficacy for neurological and psychiatric disorders. When applied for therapeutic applications, these techniques suffer from limitations that hinder the progression of its intended use to treat compromised brain function. DBS requires an invasive surgical procedure that surfaces complications from infection, longevity of electrical components, …

Contributors
Tufail, Yusuf, Tyler, William J, Duch, Carsten, et al.
Created Date
2011

Patients with Alzheimer's disease (AD) exhibit a significantly higher incidence of unprovoked seizures compared to age-matched non-AD controls, and animal models of AD (i.e., transgenic human amyloid precursor protein, hAPP mice) display neural hyper-excitation and epileptic seizures. Hyperexcitation is particularly important because it contributes to the high incidence of epilepsy in AD patients as well as AD-related synaptic deficits and neurodegeneration. Given that there is significant amyloid-β (Aβ) accumulation and deposition in AD brain, Aβ exposure ultimately may be responsible for neural hyper-excitation in both AD patients and animal models. Emerging evidence indicates that α7 nicotinic acetylcholine receptors (α7-nAChR) are …

Contributors
Liu, Qiang, Wu, Jie, Lukas, Ronald J, et al.
Created Date
2011

Cognitive function is multidimensional and complex, and research indicates that it is impacted by age, lifetime experience, and ovarian hormone milieu. One particular domain of cognitive function that is susceptible to age-related decrements is spatial memory. Cognitive practice can affect spatial memory when aged in both males and females, and in females alone ovarian hormones have been found to alter spatial memory via modulating brain microstructure and function in many of the same brain areas affected by aging. The research in this dissertation has implications that promote an understanding of the effects of cognitive practice on aging memory, why males …

Contributors
Talboom, Joshua Siegfried, Bimonte-Nelson, Heather A, Conrad, Cheryl D, et al.
Created Date
2011

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 …

Contributors
Williams, Stephanie Mitchell, Hoffman, Steven A, Conrad, Cheryl, et al.
Created Date
2011

Sensory gating is a process by which the nervous system preferentially admits stimuli that are important for the organism while filtering out those that may be meaningless. An optimal sensory gate cannot be static or inflexible, but rather plastic and informed by past experiences. Learning enables sensory gates to recognize stimuli that are emotionally salient and potentially predictive of positive or negative outcomes essential to survival. Olfaction is the only sensory modality in mammals where sensory inputs bypass conventional thalamic gating before entering higher emotional or cognitive brain regions. Thus, olfactory bulb circuits may have a heavier burden of sensory …

Contributors
Li, Monica Mo, Tyler, William J, Smith, Brian H, et al.
Created Date
2012

One explanation for membrane accommodation in response to a slowly rising current, and the phenomenon underlying the dynamics of elliptic bursting in nerves, is the mathematical problem of dynamic Hopf bifurcation. This problem has been studied extensively for linear (deterministic and stochastic) current ramps, nonlinear ramps, and elliptic bursting. These studies primarily investigated dynamic Hopf bifurcation in space-clamped excitable cells. In this study we introduce a new phenomenon associated with dynamic Hopf bifurcation. We show that for excitable spiny cables injected at one end with a slow current ramp, the generation of oscillations may occur an order one distance away …

Contributors
Bilinsky, Lydia, Baer, Steven M, Crook, Sharon M, et al.
Created Date
2012

Our ability to estimate the position of our body parts in space, a fundamentally proprioceptive process, is crucial for interacting with the environment and movement control. For proprioception to support these actions, the Central Nervous System has to rely on a stored internal representation of the body parts in space. However, relatively little is known about this internal representation of arm position. To this end, I developed a method to map proprioceptive estimates of hand location across a 2-d workspace. In this task, I moved each subject's hand to a target location while the subject's eyes were closed. After returning …

Contributors
Rincon Gonzalez, Liliana, Helms Tillery, Stephen I, Buneo, Christopher A, et al.
Created Date
2012

Spinal cord injury (SCI) disrupts the communication between supraspinal circuits and spinal circuits distal to the injury. This disruption causes changes in the motor abilities of the affected individual, but it can also be used as an opportunity to study motor control in the absence or limited presence of control from the brain. In the case of incomplete paraplegia, locomotion is impaired and often results in increased incidence of foot drag and decreased postural stability after injury. The overall goal of this work is to understand how changes in kinematics of movement and neural control of muscles effect locomotor coordination …

Contributors
Hillen, Brian, Jung, Ranu, Abbas, James, et al.
Created Date
2012

Dopamine (DA) is a neurotransmitter involved in attention, goal oriented behavior, movement, reward learning, and short term and working memory. For the past four decades, mathematical and computational modeling approaches have been useful in DA research, and although every modeling approach has limitations, a model is an efficient way to generate and explore hypotheses. This work develops a model of DA dynamics in a representative, single DA neuron by integrating previous experimental, theoretical and computational research. The model consists of three compartments: the cytosol, the vesicles, and the extracellular space and forms the basis of a new mathematical paradigm for …

Contributors
Tello-Bravo, David, Crook, Sharon M, Greenwood, Priscilla E, et al.
Created Date
2012

Interictal spikes, together with seizures, have been recognized as the two hallmarks of epilepsy, a brain disorder that 1% of the world's population suffers from. Even though the presence of spikes in brain's electromagnetic activity has diagnostic value, their dynamics are still elusive. It was an objective of this dissertation to formulate a mathematical framework within which the dynamics of interictal spikes could be thoroughly investigated. A new epileptic spike detection algorithm was developed by employing data adaptive morphological filters. The performance of the spike detection algorithm was favorably compared with others in the literature. A novel spike spatial synchronization …

Contributors
Krishnan, Balu, Iasemidis, Leonidas, Tsakalis, Kostantinos, et al.
Created Date
2012

Dendrites are the structures of a neuron specialized to receive input signals and to provide the substrate for the formation of synaptic contacts with other cells. The goal of this work is to study the activity-dependent mechanisms underlying dendritic growth in a single-cell model. For this, the individually identifiable adult motoneuron, MN5, in Drosophila melanogaster was used. This dissertation presents the following results. First, the natural variability of morphological parameters of the MN5 dendritic tree in control flies is not larger than 15%, making MN5 a suitable model for quantitative morphological analysis. Second, three-dimensional topological analyses reveals that different parts …

Contributors
Vonhoff, Fernando Jaime, Duch, Carsten J, Smith, Brian H, et al.
Created Date
2012

The ability to plan, execute, and control goal oriented reaching and grasping movements is among the most essential functions of the brain. Yet, these movements are inherently variable; a result of the noise pervading the neural signals underlying sensorimotor processing. The specific influences and interactions of these noise processes remain unclear. Thus several studies have been performed to elucidate the role and influence of sensorimotor noise on movement variability. The first study focuses on sensory integration and movement planning across the reaching workspace. An experiment was designed to examine the relative contributions of vision and proprioception to movement planning by …

Contributors
Apker, Gregory, Buneo, Christopher A, Helms Tillery, Stephen, et al.
Created Date
2012

Each year, millions of aging women will experience menopause, a transition from reproductive capability to reproductive senescence. In women, this transition is characterized by depleted ovarian follicles, declines in levels of sex hormones, and a dysregulation of gonadotrophin feedback loops. Consequently, menopause is accompanied by hot flashes, urogenital atrophy, cognitive decline, and other symptoms that reduce quality of life. To ameliorate these negative consequences, estrogen-containing hormone therapy is prescribed. Findings from clinical and pre-clinical research studies suggest that menopausal hormone therapies can benefit memory and associated neural substrates. However, findings are variable, with some studies reporting null or even detrimental …

Contributors
Engler-Chiurazzi, Elizabeth, Bimonte-Nelson, Heather A, Sanabria, Federico, et al.
Created Date
2013

Intracortical microstimulation (ICMS) within somatosensory cortex can produce artificial sensations including touch, pressure, and vibration. There is significant interest in using ICMS to provide sensory feedback for a prosthetic limb. In such a system, information recorded from sensors on the prosthetic would be translated into electrical stimulation and delivered directly to the brain, providing feedback about features of objects in contact with the prosthetic. To achieve this goal, multiple simultaneous streams of information will need to be encoded by ICMS in a manner that produces robust, reliable, and discriminable sensations. The first segment of this work focuses on the discriminability …

Contributors
Overstreet, Cynthia Kay, Helms Tillery, Stephen I, Santos, Veronica, et al.
Created Date
2013

It is commonly known that the left hemisphere of the brain is more efficient in the processing of verbal information, compared to the right hemisphere. One proposal suggests that hemispheric asymmetries in verbal processing are due in part to the efficient use of top-down mechanisms by the left hemisphere. Most evidence for this comes from hemispheric semantic priming, though fewer studies have investigated verbal memory in the cerebral hemispheres. The goal of the current investigations is to examine how top-down mechanisms influence hemispheric asymmetries in verbal memory, and determine the specific nature of hypothesized top-down mechanisms. Five experiments were conducted …

Contributors
Tat, Michael Jon, Azuma, Tamiko, Goldinger, Stephen D, et al.
Created Date
2013

Induced pluripotent stem cells (iPSCs) are an intriguing approach for neurological disease modeling, because neural lineage-specific cell types that retain the donors' complex genetics can be established in vitro. The statistical power of these iPSC-based models, however, is dependent on accurate diagnoses of the somatic cell donors; unfortunately, many neurodegenerative diseases are commonly misdiagnosed in live human subjects. Postmortem histopathological examination of a donor's brain, combined with premortem clinical criteria, is often the most robust approach to correctly classify an individual as a disease-specific case or unaffected control. We describe the establishment of primary dermal fibroblasts cells lines from 28 …

Contributors
Hjelm, Brooke Erika, Craig, David W., Wilson-Rawls, Norma J., et al.
Created Date
2013

Intermittent social defeat stress induces cross-sensitization to psychostimulants and escalation of drug self-administration. These behaviors could result from the stress-induced neuroadaptation in the mesocorticolimbic dopamine circuit. Brain-derived neurotrophic factor (BDNF) in the ventral tegmental area (VTA) is persistently elevated after social defeat stress, and may contribute to the stress-induced neuroadaptation in the mesocorticolimbic dopamine circuit. BDNF modulates synaptic plasticity, and facilitates stress- and drug-induced neuroadaptations in the mesocorticolimbic system. The present research examined the role of mesolimbic BDNF signaling in social defeat stress-induced cross-sensitization to psychostimulants and the escalation of cocaine self-administration in rats. We measured drug taking behavior with …

Contributors
Wang, Junshi, Hammer, Ronald, Feuerstein, Burt, et al.
Created Date
2013

Humans' ability to perform fine object and tool manipulation is a defining feature of their sensorimotor repertoire. How the central nervous system builds and maintains internal representations of such skilled hand-object interactions has attracted significant attention over the past three decades. Nevertheless, two major gaps exist: a) how digit positions and forces are coordinated during natural manipulation tasks, and b) what mechanisms underlie the formation and retention of internal representations of dexterous manipulation. This dissertation addresses these two questions through five experiments that are based on novel grip devices and experimental protocols. It was found that high-level representation of manipulation …

Contributors
Fu, Qiushi, Santello, Marco, Helms Tillery, Stephen, et al.
Created Date
2013

Advances in implantable MEMS technology has made possible adaptive micro-robotic implants that can track and record from single neurons in the brain. Development of autonomous neural interfaces opens up exciting possibilities of micro-robots performing standard electrophysiological techniques that would previously take researchers several hundred hours to train and achieve the desired skill level. It would result in more reliable and adaptive neural interfaces that could record optimal neural activity 24/7 with high fidelity signals, high yield and increased throughput. The main contribution here is validating adaptive strategies to overcome challenges in autonomous navigation of microelectrodes inside the brain. The following …

Contributors
Anand, Sindhu, Muthuswamy, Jitendran, Tillery, Stephen H, et al.
Created Date
2013

The brain is a fundamental target of the stress response that promotes adaptation and survival but the repeated activation of the stress response has the potential alter cognition, emotion, and motivation, key functions of the limbic system. Three structures of the limbic system in particular, the hippocampus, medial prefrontal cortex (mPFC), and amygdala, are of special interest due to documented structural changes and their implication in post-traumatic stress disorder (PTSD). One of many notable chronic stress-induced changes include dendritic arbor restructuring, which reflect plasticity patterns in parallel with the direction of alterations observed in functional imaging studies in PTSD patients. …

Contributors
Hoffman, Ann, Conrad, Cheryl D, Olive, M. Foster, et al.
Created Date
2013

Specific dendritic morphologies are a hallmark of neuronal identity, circuit assembly, and behaviorally relevant function. Despite the importance of dendrites in brain health and disease, the functional consequences of dendritic shape remain largely unknown. This dissertation addresses two fundamental and interrelated aspects of dendrite neurobiology. First, by utilizing the genetic power of Drosophila melanogaster, these studies assess the developmental mechanisms underlying single neuron morphology, and subsequently investigate the functional and behavioral consequences resulting from developmental irregularity. Significant insights into the molecular mechanisms that contribute to dendrite development come from studies of Down syndrome cell adhesion molecule (Dscam). While these findings …

Contributors
Hutchinson, Katie Marie, Duch, Carsten, Neisewander, Janet, et al.
Created Date
2013

5-HT2A receptor (R) antagonists and 5-HT2CR agonists attenuate reinstatement of cocaine-seeking behavior (i.e., incentive motivation). 5-HT2Rs are distributed throughout the brain, primarily in regions involved in reward circuitry, including the prefrontal cortex (PFC), caudate putamen (CPu), and basolateral (BlA) and central (CeA) amygdala. Using animal models, we tested our hypotheses that 5-HT2ARs in the medial (m) PFC mediate the incentive motivational effects of cocaine and cocaine-paired cues; 5-HT2ARs and 5-HT2CRs interact to attenuate cocaine hyperlocomotion and functional neuronal activation (i.e, Fos protein); and 5-HT2CRs in the BlA mediate the incentive motivational effects of cocaine-paired cues and anxiety-like behavior, while 5-HT2CRs …

Contributors
Pockros, Lara Ann, Neisewander, Janet L, Olive, Michael F, et al.
Created Date
2013

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 …

Contributors
Da Silva, Flavio J.K., Mcbeath, Michael K, Helms Tillery, Stephen, et al.
Created Date
2013

Patients with schizophrenia have deficits in sensorimotor gating, the ability to gate out irrelevant stimuli in order to attend to relevant stimuli. Prepulse inhibition (PPI) of the startle response is a reliable and valid model of sensorimotor gating across species. Repeated D2-like agonist treatment alleviates prior PPI deficits in rats, termed a PPI recovery, and is observable 28 days after treatment. The aim of the current project is to illuminate the underlying mechanism for this persistent change of behavior and determine the clinical relevance of repeated D2-like agonist treatment. Our results revealed a significant increase in Delta FosB, a transcription …

Contributors
Maple, Amanda Marie, Hammer, Ronald P, Olive, Michael F, et al.
Created Date
2013

A general continuum model for simulating the flow of ions in the salt baths that surround and fill excitable neurons is developed and presented. The ion densities and electric potential are computed using the drift-diffusion equations. In addition, a detailed model is given for handling the electrical dynamics on interior membrane boundaries, including a model for ion channels in the membranes that facilitate the transfer of ions in and out of cells. The model is applied to the triad synapse found in the outer plexiform layer of the retina in most species. Experimental evidence suggests the existence of a negative …

Contributors
Jones, Jeremiah, Gardner, Carl, Gardner, Carl, et al.
Created Date
2013

Cell morphology and the distribution of voltage gated ion channels play a major role in determining a neuron's firing behavior, resulting in the specific processing of spatiotemporal synaptic input patterns. Although many studies have provided insight into the computational properties arising from neuronal structure as well as from channel kinetics, no comprehensive theory exists which explains how the interaction of these features shapes neuronal excitability. In this study computational models based on the identified Drosophila motoneuron (MN) 5 are developed to investigate the role of voltage gated ion channels, the impact of their densities and the effects of structural features. …

Contributors
Berger, Sandra Daniela, Crook, Sharon, Baer, Steven, et al.
Created Date
2014

Patients with schizophrenia have impaired cognitive flexibility, as evidenced by behaviors of perseveration. Cognitive impairments may be due to dysregulation of glutamate and/or loss of neuronal plasticity in the medial prefrontal cortex (mPFC). The purpose of these studies was to examine the effects of mGluR5 positive allosteric modulators (PAMs) alone and in combination with the NMDAR antagonist MK-801, a pharmacological model of schizophrenia. An operant-based cognitive set-shifting task was utilized to assess cognitive flexibility, in vivo microdialysis procedures to measure extracellular glutamate levels in the mPFC, and diolistic labeling to assess the effects on dendritic spine density and morphology in …

Contributors
LaCrosse, Amber, Olive, Michael, Olive, Michael, et al.
Created Date
2014

Spatiotemporal processing in the mammalian olfactory bulb (OB), and its analog, the invertebrate antennal lobe (AL), is subject to plasticity driven by biogenic amines. I study plasticity using honey bees, which have been extensively studied with respect to nonassociative and associative based olfactory learning and memory. Octopamine (OA) release in the AL is the functional analog to epinephrine in the OB. Blockade of OA receptors in the AL blocks plasticity induced changes in behavior. I have now begun to test specific hypotheses related to how this biogenic amine might be involved in plasticity in neural circuits within the AL. OA …

Contributors
Protas, Danielle Tatiana, Smith, Brian H, Neisewander, Janet, et al.
Created Date
2014

Dexterous manipulation is a representative task that involves sensorimotor integration underlying a fine control of movements. Over the past 30 years, research has provided significant insight, including the control mechanisms of force coordination during manipulation tasks. Successful dexterous manipulation is thought to rely on the ability to integrate the sense of digit position with motor commands responsible for generating digit forces and placement. However, the mechanisms underlying the phenomenon of digit position-force coordination are not well understood. This dissertation addresses this question through three experiments that are based on psychophysics and object lifting tasks. It was found in psychophysics tasks …

Contributors
Shibata, Daisuke, Santello, Marco, Dounskaia, Natalia, et al.
Created Date
2014

Cells live in complex environments and must be able to adapt to environmental changes in order to survive. The ability of a cell to survive and thrive in a changing environment depends largely on its ability to receive and respond to extracellular signals. Initiating with receptors, signal transduction cascades begin translating extracellular signals into intracellular messages. Such signaling cascades are responsible for the regulation of cellular metabolism, cell growth, cell movement, transcription, translation, proliferation and differentiation. This dissertation seeks to dissect and examine critical signaling pathways involved in the regulation of proliferation in neural stem cells (Chapter 2) and the …

Contributors
Kusne, Yael N., Sanai, Nader, Neisewander, Janet, et al.
Created Date
2014

Animals learn to choose a proper action among alternatives according to the circumstance. Through trial-and-error, animals improve their odds by making correct association between their behavioral choices and external stimuli. While there has been an extensive literature on the theory of learning, it is still unclear how individual neurons and a neural network adapt as learning progresses. In this dissertation, single units in the medial and lateral agranular (AGm and AGl) cortices were recorded as rats learned a directional choice task. The task required the rat to make a left/right side lever press if a light cue appeared on the …

Contributors
Mao, Hongwei, Si, Jennie, Buneo, Christopher, et al.
Created Date
2014

Learning by trial-and-error requires retrospective information that whether a past action resulted in a rewarded outcome. Previous outcome in turn may provide information to guide future behavioral adjustment. But the specific contribution of this information to learning a task and the neural representations during the trial-and-error learning process is not well understood. In this dissertation, such learning is analyzed by means of single unit neural recordings in the rats' motor agranular medial (AGm) and agranular lateral (AGl) while the rats learned to perform a directional choice task. Multichannel chronic recordings using implanted microelectrodes in the rat's brain were essential to …

Contributors
Yuan, Yuan, Si, Jennie, Buneo, Christopher, et al.
Created Date
2014

The basal ganglia are four sub-cortical nuclei associated with motor control and reward learning. They are part of numerous larger mostly segregated loops where the basal ganglia receive inputs from specific regions of cortex. Converging on these inputs are dopaminergic neurons that alter their firing based on received and/or predicted rewarding outcomes of a behavior. The basal ganglia's output feeds through the thalamus back to the areas of the cortex where the loop originated. Understanding the dynamic interactions between the various parts of these loops is critical to understanding the basal ganglia's role in motor control and reward based learning. …

Contributors
Baldwin, Nathan A., Helms Tillery, Stephen I, Castañeda, Edward, et al.
Created Date
2014

The recent spotlight on concussion has illuminated deficits in the current standard of care with regard to addressing acute and persistent cognitive signs and symptoms of mild brain injury. This stems, in part, from the diffuse nature of the injury, which tends not to produce focal cognitive or behavioral deficits that are easily identified or tracked. Indeed it has been shown that patients with enduring symptoms have difficulty describing their problems; therefore, there is an urgent need for a sensitive measure of brain activity that corresponds with higher order cognitive processing. The development of a neurophysiological metric that maps to …

Contributors
Utianski, Rene Lynn, Liss, Julie M, Berisha, Visar, et al.
Created Date
2014

During the past five decades neurosurgery has made great progress, with marked improvements in patient outcomes. These noticeable improvements of morbidity and mortality can be attributed to the advances in innovative technologies used in neurosurgery. Cutting-edge technologies are essential in most neurosurgical procedures, and there is no doubt that neurosurgery has become heavily technology dependent. With the introduction of any new modalities, surgeons must adapt, train, and become thoroughly familiar with the capabilities and the extent of application of these new innovations. Within the past decade, endoscopy has become more widely used in neurosurgery, and this newly adopted technology is …

Contributors
Elhadi, Ali M., Preul, Mark C, Towe, Bruce, et al.
Created Date
2014

Glioblastoma (GBM) is the most common primary brain tumor with an incidence of approximately 11,000 Americans. Despite decades of research, average survival for GBM patients is a modest 15 months. Increasing the extent of GBM resection increases patient survival. However, extending neurosurgical margins also threatens the removal of eloquent brain. For this reason, the infiltrative nature of GBM is an obstacle to its complete resection. We hypothesize that targeting genes and proteins that regulate GBM motility, and developing techniques that safely enhance extent of surgical resection, will improve GBM patient survival by decreasing infiltration into eloquent brain regions and enhancing …

Contributors
Georges, Joseph, Feuerstein, Burt G, Smith, Brian H, et al.
Created Date
2014

ABSTRACT Auditory hallucinations are a characteristic symptom of schizophrenia. Research has documented that the auditory cortex is metabolically activated when this process occurs, and that imbalances in the dopaminergic transmission in the striatum contribute to its physiopathology. Most animal models have focused the effort on pharmacological approaches like non-competitive N-methyl-D-aspartate (NMDA) receptor antagonists to produce activation of the auditory cortex, or dopamine antagonists to alleviate it. I hypothesize that these perceptual phenomena can be explained by an imbalance activation of spiny projecting neurons in the striatal pathways, whereby supersensitive postsynaptic D2-like receptor, signaling in the posterior caudatoputamen generates activation of …

Contributors
Parga Becerra, Alejandro, Neisewander, Janet, Hammer, Ronald, et al.
Created Date
2014

As the application of interactive media systems expands to address broader problems in health, education and creative practice, they fall within a higher dimensional space for which it is inherently more complex to design. In response to this need an emerging area of interactive system design, referred to as experiential media systems, applies hybrid knowledge synthesized across multiple disciplines to address challenges relevant to daily experience. Interactive neurorehabilitation (INR) aims to enhance functional movement therapy by integrating detailed motion capture with interactive feedback in a manner that facilitates engagement and sensorimotor learning for those who have suffered neurologic injury. While …

Contributors
Lehrer, Nicole, Rikakis, Thanassis, Rikakis, Thanassis, et al.
Created Date
2014

During attempted fixation, the eyes are not still but continue to produce so called "fixational eye movements", which include microsaccades, drift, and tremor. Microsaccades are thought to help prevent and restore vision loss during fixation, and to correct fixation errors, but how they contribute to these functions remains a matter of debate. This dissertation presents the results of four experiments conducted to address current controversies concerning the role of microsaccades in visibility and oculomotor control. The first two experiments set out to correlate microsaccade production with the visibility of foveal and peripheral targets of varied spatial frequencies, during attempted fixation. …

Contributors
Costela, Francisco, Crook, Sharon M, Martinez-Conde, Susana, et al.
Created Date
2014

Pediatric traumatic brain injury (TBI) is a leading cause of death and disability in children. When TBI occurs in children it often results in severe cognitive and behavioral deficits. Post-injury, the pediatric brain may be sensitive to the effects of TBI while undergoing a number of age-dependent physiological and neurobiological changes. Due to the nature of the developing cortex, it is important to understand how a pediatric brain recovers from a severe TBI (sTBI) compared to an adult. Investigating major cortical and cellular changes after sTBI in a pediatric model can elucidate why pediatrics go on to suffer more neurological …

Contributors
Nichols, Joshua, Anderson, Trent, Newbern, Jason, et al.
Created Date
2015

Women are exposed to numerous endogenous and exogenous hormones across the lifespan. In the last several decades, the prescription of novel hormonal contraceptives and hormone therapies (HTs) have resulted in aging women that have a unique hormone exposure history; little is known about the impact of these hormone exposures on short- and long- term brain health. The goal of my dissertation was to understand how lifetime hormone exposures shape the female cognitive phenotype using several innovative approaches, including a new human spatial working memory task, the human radial arm maze (HRAM), and several rodent menopause models with variants of clinically …

Contributors
Mennenga, Sarah Elaine, Bimonte-Nelson, Heather, Aiken, Leona, et al.
Created Date
2015

Studies in Second Language Acquisition and Neurolinguistics have argued that adult learners when dealing with certain phonological features of L2, such as segmental and suprasegmental ones, face problems of articulatory placement (Esling, 2006; Abercrombie, 1967) and somatosensory stimulation (Guenther, Ghosh, & Tourville, 2006; Waldron, 2010). These studies have argued that adult phonological acquisition is a complex matter that needs to be informed by a specialized sensorimotor theory of speech acquisition. They further suggested that traditional pronunciation pedagogy needs to be enhanced by an approach to learning offering learners fundamental and practical sensorimotor tools to advance the quality of L2 speech …

Contributors
Lima, Alberto, Pruitt, Kathryn, Van Gelderen, Elly, et al.
Created Date
2015

Brain-machine interfaces (BMIs) were first imagined as a technology that would allow subjects to have direct communication with prosthetics and external devices (e.g. control over a computer cursor or robotic arm movement). Operation of these devices was not automatic, and subjects needed calibration and training in order to master this control. In short, learning became a key component in controlling these systems. As a result, BMIs have become ideal tools to probe and explore brain activity, since they allow the isolation of neural inputs and systematic altering of the relationships between the neural signals and output. I have used BMIs …

Contributors
Armenta Salas, Michelle, Helms Tillery, Stephen I, Si, Jennie, et al.
Created Date
2015

Methyl-CpG binding protein 2 (MECP2) is a widely abundant, multifunctional regulator of gene expression with highest levels of expression in mature neurons. In humans, both loss- and gain-of-function mutations of MECP2 cause mental retardation and motor dysfunction classified as either Rett Syndrome (RTT, loss-of-function) or MECP2 Duplication Syndrome (MDS, gain-of-function). At the cellular level, MECP2 mutations cause both synaptic and dendritic defects. Despite identification of MECP2 as a cause for RTT nearly 16 years ago, little progress has been made in identifying effective treatments. Investigating major cellular and molecular targets of MECP2 in model systems can help elucidate how mutation …

Contributors
Williams, Alison Ann, Duch, Carsten, Orchinik, Miles, et al.
Created Date
2015

Locomotion in natural environments requires coordinated movements from multiple body parts, and precise adaptations when changes in the environment occur. The contributions of the neurons of the motor cortex underlying these behaviors are poorly understood, and especially little is known about how such contributions may differ based on the anatomical and physiological characteristics of neurons. To elucidate the contributions of motor cortical subpopulations to movements, the activity of motor cortical neurons, muscle activity, and kinematics were studied in the cat during a variety of locomotion tasks requiring accurate foot placement, including some tasks involving both expected and unexpected perturbations of …

Contributors
Stout, Eric, Beloozerova, Irina N, Dounskaia, Natalia, et al.
Created Date
2015

Intermittent social defeat stress produces vulnerability to drugs of abuse, a phenomena known as cross-sensitization, which is proceeded by a corresponding upregulation of ventral tegmental area (VTA) mu-opioid receptors (MORs). Since VTA MORs are implicated in the expression of psychostimulant sensitization, they may also mediate social stress-induced vulnerability to drugs of abuse. Social stress and drugs of abuse increase mesolimbic brain-derived neurotrophic factor (BDNF) signaling with its receptor, tropomyosin-related kinase B (TrkB). These studies examined whether VTA MOR signaling is important for the behavioral and cellular consequences of social stress. First, the function of VTA MORs in the behavioral consequences …

Contributors
Johnston, Caitlin Elizabeth, Hammer, Ronald P., Nikulina, Ella M., et al.
Created Date
2015

Tobacco and alcohol are the most commonly abused drugs worldwide. Many people smoke and drink together, but the mechanisms of this nicotine (NIC) -ethanol (EtOH) dependence are not fully known. EtOH has been shown to affect some nicotinic acetylcholine receptors (nAChRs), which potentially underlies NIC-EtOH codependence. Ventral Tegmental Area (VTA) dopamine (DA) and γ-aminobutyric acid (GABA) neurons express different nAChR subtypes, whose net activation results in enhancement of DA release in the Prefrontal Cortex (PFC) and Nucleus Accumbens (NAc). Enhancement of DA transmission in this mesocorticolimbic system is thought to lead to rewarding properties of EtOH and NIC, clarification of …

Contributors
Taylor, Devin, Wu, Jie, Olive, M F, et al.
Created Date
2015