Neuroscience and Neurobiology Commons^™

A Flight Sensory-Motor To Olfactory Histamine Circuit Mediates Olfactory Processing Of Ecologically And Behaviorally Natural Stimuli, Samual P. Bradley

Graduate Theses, Dissertations, and Problem Reports (ETD)

Environmental pressures have conferred species specific behavioral and morphological traits to optimize reproductive success. To optimally interact with their environment, nervous systems have evolved motor-to-sensory circuits that mediate the processing of its own reafference. Moth flight behavioral patterns to odor sources are stereotyped, presumably to optimize the likelihood of interacting with the odor source. In the moth Manduca sexta wing beating causes oscillatory flow of air over the antenna; because of this, odorant-antennal interactions are oscillatory in nature. Electroantennogram recordings on antennae show that the biophysical properties of their spiking activity can effectively track odors presented at the wing beat …

Neuroimaging Of Real-World Audio-Visual Sensory Integration In High-Functioning Autism, Paula J. Webster

Graduate Theses, Dissertations, and Problem Reports (ETD)

Sensory processing differences are a prevalent aspect of autism spectrum disorder (ASD) that may contribute to core deficits of ASD such as repetitive behaviors as well as comorbidities including anxiety disorders. The ability to integrate information among our senses is required to comprehend the world around us and is crucial for the development of language, motor skills, and social communication. Prior studies have shown that individuals with autism differ from individuals without autism when presented with simple, non-natural audio-visual stimuli such as basic shapes accompanied by pure tones. Because the human brain processes non-natural and natural stimuli differently, more recent …

C-Jun Nh2-Terminal Kinase Signaling Controls Cellular Mechanisms Of Guided Cortical Interneuron Migration, Skye Eleanor Smith

Graduate Theses, Dissertations, and Problem Reports (ETD)

The cerebral cortex is an intricately organized brain structure responsible for high-level functions including sensory perception, movement, memory, language, and cognition. During corticogenesis, cortical excitatory neurons and inhibitory interneurons migrate from their respective progenitor zones into the developing cerebral cortex, deposit in the correct cortical layer, and establish connections with their appropriate synaptic partners. The balance between excitation and inhibition is critical for cortical circuitry development and function. Aberrant migration of inhibitory interneurons can alter the formation of cortical circuitry and lead to several neurodevelopmental disorders including epilepsy, autism spectrum disorder, and schizophrenia. Therefore, elucidating the mechanisms responsible for inhibitory …

Factors Influencing Huntingtin Aggregation At Surfaces: Implications For Huntington’S Disease, Sharon E. Groover

Graduate Theses, Dissertations, and Problem Reports (ETD)

Huntington’s Disease (HD) is a genetic, neurodegenerative disease characterized by an abnormal polyglutamine (polyQ) expansion in the first exon of the huntingtin protein (htt). The polyQ domain facilitates aggregation and initiates the formation of a diverse collection of aggregate species, including fibrils, oligomers and annular aggregates. The first 17 amino acids of htt (Nt17) directly flank the polyQ domain and is a key factor in htt’s association to membranous structures. In addition to Nt17 being an amphipathic αhelix, it also promotes aggregation through self-association and contains numerous posttranslational modifications (PTMs) that can modulate toxicity and subcellular localization. For in depth …

Amazon Nights Ii: Electric Boogaloo-Neural Adaptations For Communication In Three Species Of Weakly Electric Fish, Kathryne M. Allen

Graduate Theses, Dissertations, and Problem Reports (ETD)

Sensory systems have to extract useful information from environments awash in noise and confounding input. Studying how salient signals are encoded and filtered from these natural backgrounds is a key problem in neuroscience. Communication is a particularly tractable tool for studying this problem, as it is a ubiquitous task that all organisms must accomplish, easily compared across species, and is of significant ethological relevance. In this chapter I describe the current knowledge of what is both known and still unknown about how sensory systems are adapted for the challenges of encoding conspecific signals, particularly in environments complicated by conspecific-generated noise. …

Aptamer Functionalized Zinc Oxide Field Effect Transistors For Odor Detection, Michael D. Aldridge

Graduate Theses, Dissertations, and Problem Reports (ETD)

Odor detection and identification are complex processes, and tasks that currently only animals do well. There is a pressing need for an electronic nose, or eNose, with good sensitivity, selectivity, and speed that mimics that ability. Food quality control operations, environmental sensing, occupational safety, and the defense sectors all require systems that can rapidly and reliably detect trace levels of volatile organic compounds. The goal of this work is to create a biologically inspired device which can accurately detect and identify odors at concentrations consistent with the most sensitive biological systems.

In order to mimic a natural olfactory system, we …

Neural Processing Of Communication Signals: The Extent Of Sender–Receiver Matching Varies Across Species Of Apteronotus, Kathryne M. Allen, Gary Marsat

Faculty & Staff Scholarship

As communication signal properties change, through genetic drift or selective pressure, the sensory systems that receive these signals must also adapt to maintain sensitivity and adaptability in an array of contexts. Shedding light on this process helps us to understand how sensory codes are tailored to specific tasks. In a species of weakly electric fish, Apteronotus albifrons, we examined the unique neurophysiological properties that support the encoding of electrosensory communication signals that the animal encounters in social exchanges. We compare our findings to the known coding properties of the closely related species Apteronotus leptorhynchus to establish how these animals …

Induction Of Cerebral Hyperexcitability By Peripheral Viral Challenge: Role Of Cxcl10 Chemokine, Tiffany J. Petrisko

Graduate Theses, Dissertations, and Problem Reports (ETD)

Peripheral viral infections are po­tent comorbid factors that exacerbate neuro­degene­ration. Although the under­lying mecha­nisms have not been defined, neuronal hyperexcitability has been established as an underlying feature. Our lab has developed a preclinical model in which a viral mimetic, poly­inosinic-poly­cytidylic acid (PIC) is injected in­tra­peritoneally to induce an anti-viral acute phase response (APR). APR in turn elicits robust neuronal hyperexcitability. The present study was undertaken to characterize molecular mechanisms that mediate the development of hyperexcitability in response to PIC challenge. The analysis of brain tissue after PIC challenge revealed a robust elevation of CXCL10 chemokine, indicating its putative role in …

Sodium Channel Distribution In The Apical Dendrites Of Pyramidal Cells Vary In The Hindbrain Of Apteronotus Leptorhynchus., Sree Indrani Motipally

Graduate Theses, Dissertations, and Problem Reports (ETD)

Apteronotid weakly electric fish heavily rely on their electrosensory system for behaviors like spatial navigation, communication and prey capture. Since the behaviorally important information about their environment is contained in the spatial and temporal modulations of the electrosensory signal, efficient mechanisms to process this information with great fidelity are of the utmost importance. Efficient sensory processing often involves having multiple parallel processing streams so that each stream can specialize to treat signals with different properties. This strategy requires the response properties and neural dynamic to be adjusted in each pathway to implement different neural coding strategies. One of the neural …

Role Of Extracellular Vesicles In Neuroinflammatory Progression And Mitochondrial Functional Alterations, Ashley E. Russell

Graduate Theses, Dissertations, and Problem Reports (ETD)

Inflammation within the central nervous system (CNS), termed neuroinflammation, is a defining characteristic of many neuropathological conditions, including Alzheimer’s disease (AD) and stroke. Certain inflammatory mediators activate the transcription factor NF-κB, which induces transcription of many pro-inflammatory genes, including miR-34a and miR-146a. Several target candidate genes of these miRNAs encode for proteins of the mitochondrial electron transport chain. In our studies, we demonstrate that in response to inflammatory stimuli, such as TNF-α, the expression of miR-34a and -146a is significantly increased in several CNS cell types, and in their secreted extracellular vesicles (EVs). Exposure to TNF-α-derived EVs significantly increases cellular …

Regulator Of G Protein Signaling-12 (Rgs12) In Dopaminergic And Kappa Opioid Receptor-Dependent Signaling And Behavior, Joshua David Gross

Graduate Theses, Dissertations, and Problem Reports (ETD)

Dopaminergic neurotransmission is critically involved in the etiology and treatment of many psychiatric and neurological disorders. One modulator of dopaminergic neurotransmission is the kappa opioid receptor (KOR) -- a G protein-coupled receptor (GPCR) that is densely expressed within dopaminergic neurons and circuits. GPCRs are tightly regulated by a variety of intracellular signaling molecules, including Regulator of G Protein Signaling (RGS) proteins. Canonically, RGS proteins act as GTPase accelerating proteins (GAPs) on GTP-bound Ga subunits following GPCR activation, thereby hastening the rate at which GPCR-mediated G protein signaling is terminated. However, some RGS proteins exhibit more complex mechanisms of action on …

Glial Cell Expansion And Intercellular Signaling In The Developing Medial Nucleus Of The Trapezoid Body (Mntb), Ashley N. Brandebura

Graduate Theses, Dissertations, and Problem Reports (ETD)

Neural circuit formation is a complex process involving coordinated communication between neurons, glia and vascular-associated cells (VACs). Each cell type is responsible for a unique transcriptional and translational contribution to tissue maturation. Deciphering the intercellular signaling patterns which guide neural circuit formation during normal development is thus an essential step in understanding which components of neural circuit formation go awry in neurodevelopmental disorders. The medial nucleus of the trapezoid body (MNTB), located in the auditory brainstem, was used as a model system to study the dynamics of neural circuit formation because it contains a mostly homogeneous population of postsynaptic neurons …

Discrimination And Behavioral Responses To Communication Signals Compared Across Apteronotids., Danielle Leigh Dillon-Seeger

Graduate Theses, Dissertations, and Problem Reports (ETD)

Sensory systems are often uniquely tailored to encode behaviorally relevant signals and comparative studies across species can thus reveal how evolutionary changes shape sensory functions. The structure of communication signals varies widely between ghost knifefish species. Recent findings suggest that the nervous system co-adapted to the various signal structures observed across species to support different sensory behaviors. The aim for this thesis was to compare the sensory behavior of 3 species of ghost knifefish to contrast their behavioral performance with the known differences in neurophysiology. We hypothesize that for the different signal types and species, the ability to discriminate small …

Low Sucrose, Omega-3 Enriched Diet Has Region-Specific Effects On Neuroinflammation And Synaptic Function Markers In A Mouse Model Of Doxorubicin-Based Chemotherapy, Tonya S. Orchard, Monica M. Gaudier-Diaz, Panchita Phuwamongkolwiwat-Chu, Rebecca Andridge, Maryam B. Lustberg, Joshua Bomser, Rachel M. Cole, Martha A. Belury, Courtney A. Devries

Faculty & Staff Scholarship

Chemotherapeutic agents such as doxorubicin may negatively affect long-term brain functioning in cancer survivors; neuroinflammation may play a causal role. Dietary approaches that reduce inflammation, such as lowering sucrose and increasing eicosapentaenoic acid plus docosahexaenoic acid (EPA + DHA), may attenuate chemotherapy-induced neuroinflammation and synaptic damage, thereby improving quality of life. Ovariectomized, C57BL/6 mice were assigned to a chemotherapy (9 mg/kg doxorubicin + 90 mg/kg cyclophosphamide) or vehicle two-injection regimen, with injections two and four weeks after starting diets. In Study 1, mice received low sucrose diets with EPA + DHA or No EPA + DHA for four to six …

Analytical Cpg Model Driven By Limb Velocity Input Generates Accurate Temporal Locomotor Dynamics, Sergiy Yakovenko, Anton Sobinov, Valeriya Gritsenko

Faculty & Staff Scholarship

The ability of vertebrates to generate rhythm within their spinal neural networks is essential for walking, running, and other rhythmic behaviors. The central pattern generator (CPG) network responsible for these behaviors is well-characterized with experimental and theoretical studies, and it can be formulated as a nonlinear dynam- ical system. The underlying mechanism responsible for locomotor behavior can be expressed as the process of leaky integration with resetting states generating appropriate phases for changing body velocity. The low-dimensional input to the CPG model generates the bilateral pattern of swing and stance modulation for each limb and is consistent with the desired …

Embodying Functionally Relevant Action Sounds In Patients With Spinal Cord Injury, Mariella Pazzaglia, Giulia Galli, James W. Lewis, Giorgio Scivoletto, Anna Maria Giannini, Marco Molinari

Faculty & Staff Scholarship

Growing evidence indicates that perceptual-motor codes may be associated with and influenced by actual bodily states. Following a spinal cord injury (SCI), for example, individuals exhibit reduced visual sensitivity to biological motion. However, a dearth of direct evidence exists about whether profound alterations in sensorimotor traffic between the body and brain influence audio-motor representations. We tested 20 wheelchair-bound individuals with lower skeletal-level SCI who were unable to feel and move their lower limbs, but have retained upper limb function. In a two-choice, matching-to-sample auditory discrimination task, the participants were asked to determine which of two action sounds matched a sample …

Respiratory Muscle Training Positively Affects Vasomotor Response In Young Healthy Women, Angela Valentina Bisconti, Michela Devoto, Massimo Venturelli, Randall Bryner, Mark Olfert, Paul D. Chantler, F. Esposito

Faculty & Staff Scholarship

Vasomotor response is related to the capacity of the vessel to maintain vascular tone within a narrow range. Two main control mechanisms are involved: the autonomic control of the sympathetic neural drive (global control) and the endothelial smooth cells capacity to respond to mechanical stress by releasing vasoactive factors (peripheral control). The aim of this study was to evaluate the effects of respiratory muscle training (RMT) on vasomotor response, assessed by flow-mediated dilation (FMD) and heart rate variability, in young healthy females. The hypothesis was that RMT could enhance the balance between sympa- thetic and parasympathetic neural drive and reduce …

Maternal Engineered Nanomaterial Inhalation During Gestation Alters The Fetal Transcriptome, P.A. Stapleton, Q.A. Hathaway, C.E. Nichols, A.B. Abukabda, M.V. Pinti, D.L. Shepherd, C.R. Mcbride, J. Yi, V.C. Castranova, J.M Hollander, Timothy Robert Nurkiewicz

Faculty & Staff Scholarship

Background: The integration of engineered nanomaterials (ENM) is well-established and widespread in clinical, commercial, and domestic applications. Cardiovascular dysfunctions have been reported in adult populations after exposure to a variety of ENM. As the diversity of these exposures continues to increase, the fetal ramifications of maternal exposures have yet to be determined. We, and others, have explored the consequences of ENM inhalation during gestation and identified many cardiovascular and metabolic outcomes in the F1 generation. The purpose of these studies was to identify genetic alterations in the F1 generation of Sprague-Dawley rats that result from maternal ENM inhalation during gestation. …

Absolute Lymphocyte And Neutrophil Counts In Neonatal Ischemic Brain Injury, Jessica M. Povroznik, Elizabeth B. Engler-Chiurazzi, Tania Nanavati, Paola Pergami

Faculty & Staff Scholarship

Objectives: This study aimed to identify differences in absolute neutrophils, lymphocytes, and neutrophil-to-lymphocyte ratio between neonates with two forms of ischemic brain injury, hypoxic-ischemic encephalopathy, and acute ischemic stroke, compared to controls. We also aimed to determine whether this neutrophil/lymphocyte response pattern is associated with disease severity or is a consequence of the effects of total-body cooling, an approved treatment for moderate-to-severe hypoxic-ischemic encephalopathy. Methods: A retrospective chart review of 101 neonates with hypoxic-ischemic encephalopathy + total-body cooling (n = 26), hypoxic-ischemic encephalopathy (n=12), acute ischemic stroke (n=15), and transient tachypnea of the newborn (n=48) was conducted; transient tachypnea of …

Discerning Suicide In Drug Intoxication Deaths: Paucity And Primacy Of Suicide Notes And Psychiatric History, Ian Rh Rockett, Eric D. Caine, Hilary S. Connery, Gail D'Onofrio, David J. Gunnell, Ted R. Miller, Kurt B. Nolte, Mark S. Kaplan, Nestor D. Kapusta, Christa L. Lilly, Lewis S. Nelson, Sandra L. Putnam, Steven Stack, Peeter Varnik, Lynne R. Webster, Haomiao Jia

Faculty & Staff Scholarship

Objective

A paucity of corroborative psychological and psychiatric evidence may be inhibiting detec- tion of drug intoxication suicides in the United States. We evaluated the relative importance of suicide notes and psychiatric history in the classification of suicide by drug intoxication versus firearm (gunshot wound) plus hanging/suffocation—the other two major, but overtly violent methods.

Methods

This observational multilevel (individual/county), multivariable study employed a general- ized linear mixed model (GLMM) to analyze pooled suicides and undetermined intent deaths, as possible suicides, among the population aged 15 years and older in the 17 states participating in the National Violent Death Reporting System …

Acute Effects Of Diets Rich In Almonds And Walnuts On Endothelial Function, Ravindra Bhardwaj, Harvinder Dod, Manjinder S. Sandhu, Rohil Bedi, Sachin Dod, Gregory Konat, H.K. Chopra, Rakesh Sharma, Abnash C. Jain, Navin Nanda

Faculty & Staff Scholarship

Objective: Omega-3 fatty acids, especially alpha-linolenic acid (ALA), which are present in nuts may reduce cardiovascular disease (CVD) risk, by changing vascular inflammation and improving endothelial dysfunction. The objective of the study was to evaluate the acute effects of two different diets, one containing walnuts and the other almonds on endothelial function.

Methods: Twenty-seven overweight volunteers underwent a randomized 2-period, crossover, controlled intervention study. The subjects were given either walnut or almond diets which varied in monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA) content. The walnut diet provided 23.1% energy from PUFA and the almond diet provided 7.6% …

Polarity And Competition In The Development Of The Calyx Of Held Terminal In The Medial Nucleus Of The Trapezoid Body In The Mouse, Paul Steven Holcomb

Graduate Theses, Dissertations, and Problem Reports (ETD)

In the auditory brainstem, the connection between globular bushy cells of the anteroventral cochlear nucleus and principal cells (PCs) of the medial nucleus of the trapezoid body (MNTB) is created by one of the largest nerve terminals in the central nervous system, the calyx of Held (CH). The characteristics of the CH:MNTB connection—a short developmental period (48-72 hours), accessibility for recording from pre- and postsynaptic components, and clear monoinnervated end point—make this system an ideal model system for studying nervous system development. Model systems undergo stereotyped stages of development, including exuberant overinnervation, competition between terminals, and a refinement of innervation …

The Integration Of Extrinsic And Intrinsic Neuromodulators In The Olfactory System, Kristyn M. Lizbinski

Graduate Theses, Dissertations, and Problem Reports (ETD)

Neuromodulation is a ubiquitous feature of neural systems, allowing flexible, context specific control over network dynamics by adjusting the biophysical and synaptic properties of neurons. Neuromodulation was first described in invertebrate motor systems and early work established a basic dichotomy for neuromodulation as having either an intrinsic origin (i.e. neurons that participate in network coding) or an extrinsic origin (i.e. neurons from independent networks). Although this dichotomy has been thoroughly considered in motor systems, it has received far less attention in sensory systems. Furthermore, nervous systems are continually subject to a dynamic cocktail of both intrinsic and extrinsic modulators. However, …