Neuroscience and Neurobiology Commons^™

Investigating Anatomical And Molecular Aspects Of Proprioceptive Sensory Neuron Diversity Using A Transgenic Mouse Model, Martha Jean Sonner

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Muscle spindles (MS) and Golgi tendon organs (GTOs) are encapsulated, stretch-activated sensory receptors housed within skeletal muscles, yet their functional contributions to proprioceptive monitoring of limb movements are quite different. For example, MS are responsible for detecting stretch of muscle fibers, and GTOs provide feedback regarding muscle tension during contraction. Peripheral axons extending from proprioceptive sensory neurons (PSNs) in the dorsal root ganglia supply MS and GTOs. MS are innervated by Group Ia and II sensory fiber endings, while GTOs are innervated by a single Group Ib sensory fiber. The developmental processes guiding axons from PSNs to their targets and …

Effects Of Transcranial Direct Current Stimulation On Expression Of Immediate Early Genes (Ieg's), Jessica Wagner

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Transcranial direct current stimulation (tDCS) has been utilized in human studies to modulate a multitude of psychological, cognitive, and psychiatric disorders. There have been positive behavioral results in human subjects but our knowledge of biological processes occurring during stimulation to elicit behavioral outcomes is limited. Our study utilizes a rodent tDCS (R-tDCS) model in which Sprague Dawley rats receive tDCS in order to examine whether tDCS affects neuronal activation. We examined two immediate early genes (IEG's), cFos and zif268, in order to discern if tDCS affects neuronal activation. Our findings indicate that tDCS does affect neuronal activation by means of …

Dopaminergic And Activity-Dependent Modulation Of Mechanosensory Responses In Drosophila Melanogaster Larvae, Josh S. Titlow

Theses and Dissertations--Biology

A central theme of this dissertation is nervous system plasticity. Activity-dependent plasticity and dopaminergic modulation are two processes by which neural circuits adapt their function to developmental and environmental changes. These processes are involved in basic cognitive functions and can contribute to neurological disorder. An important goal in modern neurobiology is understanding how genotypic variation influences plasticity, and leveraging the quantitative genetics resources in model organisms is a valuable component of this endeavor. To this end I investigated activity-dependent plasticity and dopaminergic modulation in Drosophila melanogaster larvae using neurobiological and genetic approaches.

Larval mechanosensory behavior is described in Chapter 2. …

Variance Predicts Salience In Central Sensory Processing, Ann M. Hermundstad, John J. Briguglio, Mary M. Conte, Jonathan D. Victor, Vijay Balasubramanian, Gašper Tkačik

Publications and Research

Information processing in the sensory periphery is shaped by natural stimulus statistics. In the periphery, a transmission bottleneck constrains performance; thus efficient coding implies that natural signal components with a predictably wider range should be compressed. In a different regime—when sampling limitations constrain performance—efficient coding implies that more resources should be allocated to informative features that are more variable. We propose that this regime is relevant for sensory cortex when it extracts complex features from limited numbers of sensory samples. To test this prediction, we use central visual processing as a model: we show that visual sensitivity for local multi-point …

Amyotrophic Lateral Sclerosis: Mechanism Behind Mutant Sod Toxicity And Improving Current Therapeutic Strategies, Cassandra Dennys

Electronic Theses and Dissertations

Amyotrophic Lateral Sclerosis (ALS) is an always lethal motor neuron disease with unknown pathogenesis. Inhibitors of the molecular chaperone heat shock protein 90 (Hsp90) have limited neuroprotection in some models of motor neuron degeneration. However the direct effect of Hsp90 inhibition on motor neurons is unknown. Here we show that Hsp90 inhibition induced motor neuron death through activation of the P2X7 receptor. Motor neuron death required phosphatase and tensein homolog (PTEN)-mediated inhibition of the PI3K/AKT pathway leading to Fas receptor activation and caspase dependent death. The relevance of Hsp90 for motor neuron survival was investigated in mutant Cu/Zn superoxide dismutase …

The Effects Of Anxiety On Sensory Gating, Jonathon Meier

Honors Projects

Sensory gating is a proposed important physiological process of inhibiting neuronal responses of repetitious stimuli in the central nervous system to allocate more cognitive resources to additional salient information. Sensory gating is currently being studied to better understand psychiatric illnesses, especially those characterized by emotional changes and the inability to concentrate such as schizophrenia, ADHD, anxiety disorder, and Parkinson’s. Anxiety is a strong feeling of nervousness that occurs in all individuals at varying degrees and is associated with detrimental health effects as well as hindering concentration. Numerous brain regions are associated with anxiety levels such as the anterior limbic system, …

Neuroscientists In Court, Owen D. Jones, Anthony D. Wagner, David L. Faigman, Marcus E. Raichle

Vanderbilt Law School Faculty Publications

Neuroscientific evidence is increasingly being offered in court cases. Consequently, the legal system needs neuroscientists to act as expert witnesses who can explain the limitations and interpretations of neuroscientific findings so that judges and jurors can make informed and appropriate inferences. The growing role of neuroscientists in court means that neuroscientists should be aware of important differences between the scientific and legal fields, and, especially, how scientific facts can be easily misunderstood by non-scientists,including judges and jurors.

This article describes similarities, as well as key differences, of legal and scientific cultures. And it explains six key principles about neuroscience that …

Quantification Of Protoporphyrin Ix Accumulation In Glioblastoma Cells – A New Technique, John E Lawrence

Journal Articles

5-Aminolevulinic Acid (5-ALA) is a precursor of heme synthesis. A metabolite, protoporphyrin IX (PpIX), selectively accumulates in neoplastic tissue including glioblastoma. Presurgical administration of 5-ALA forms the basis of fluorescence-guided resection (FGR) of glioblastoma (GBM) tumors. However, not all gliomas accumulate sufficient quantities of PpIX to fluoresce, thus limiting the utility of FGR. We therefore developed an assay to determine cellular and pharmacological factors that impact PpIX fluorescence in GBM. This assay takes advantage of a GBM cell line engineered to express yellow fluorescent protein. Methods. The human GBM cell line U87MG was transfected with a YFP expression vector. After …

Testing A Structural Equation Model Of Language-Based Cognitive Fitness, Elizabeth Ann Moxley-Paquette

Walden Dissertations and Doctoral Studies

The normative development of language is often taken for granted, yet problems with language development can result in stress for the individual and family. A challenge with these language development problems lies within the contemporary education system, which assumes that children have appropriate skills when they begin school. The purpose of the study was to test a theoretical model of language readiness known as language-based cognitive fitness, which includes measures associated with structural concepts of language involving receptive language, expressive language, spontaneous narrative speech, and writing fluency. The sample included children from a private school who received an extensive battery …

Inhibition Of Phosphodiesterase10a Attenuates Morphine-Induced Conditioned Place Preference, Ying Mu, Zhaoxiang Ren, Jia Jia, Bo Gao, Longtai Zheng, Eitan Friedman

Publications and Research

Background: Phosphodiesterase (PDE) 10A is selectively expressed in medium spiny neurons of the striatum. Nucleus accumbens (NAc) is a key region that mediates drug reward and addiction-related behaviors. To investigate the potential role of PDE10A in the reinforcement properties of morphine, we tested the effect of MP-10, a selective inhibitor of PDE10A, on acquisition, expression, and extinction of morphine-induced conditioned place preference (CPP).

Results: The results show that 2.5 mg/kg MP-10, administered subcutaneously, significantly inhibited the acquisition of morphine-induced CPP. The same dose of MP-10 alone did not result in the CPP. Moreover, MP-10 did not alter the expression of …

The Molecular Components Of Estrogen Receptor Beta (Erβ) Signaling In Neuronal Sytems, Natasha Mott

Dissertations

With increasing life expectancy, women are now living upwards of 50 years without circulating estrogens, therefore, it is essential to investigate how the brain is changed by estrogen deprivation and also how aging influences these changes. The Women's Health Initiative (WHI) study spurred rigorous debate regarding estrogen therapy for postmenopausal women due to dichotomous effects of estrogens in menopausal and post-menopausal women. Meta-analyses of the WHI study revealed that after circulating estrogens are depleted for many years re-exposure may cause aberrant, negative health effects, indicating that there is an age-related `switch' in estrogen signaling around menopause. These age-related effects of …

A Systems Biology Approach To Detect Eqtls Associated With Mirna And Mrna Co-Expression Networks In The Nucleus Accumbens Of Chronic Alcoholic Patients, Mohammed Mamdani

Theses and Dissertations

Alcohol Dependence (AD) is a chronic substance use disorder with moderate heritability (60%). Linkage and genome-wide association studies (GWAS) have implicated a number of loci; however, the molecular mechanisms underlying AD are unclear. Advances in systems biology allow genome-wide expression data to be integrated with genetic data to detect expression quantitative trait loci (eQTL), polymorphisms that regulate gene expression levels, influence phenotypes and are significantly enriched among validated genetic signals for many commonly studied traits including AD.

We integrated genome-wide mRNA and miRNA expression data with genotypic data from the nucleus accumbens (NAc), a major addiction-related brain region, of 36 …

Methods For Integrative Analysis Of Genomic Data, Paul Manser

Theses and Dissertations

In recent years, the development of new genomic technologies has allowed for the investigation of many regulatory epigenetic marks besides expression levels, on a genome-wide scale. As the price for these technologies continues to decrease, study sizes will not only increase, but several different assays are beginning to be used for the same samples. It is therefore desirable to develop statistical methods to integrate multiple data types that can handle the increased computational burden of incorporating large data sets. Furthermore, it is important to develop sound quality control and normalization methods as technical errors can compound when integrating multiple genomic …

Time, Perspectives, Verbs, And Imagining Events, Jeffrey P. Hong

Theses and Dissertations (Comprehensive)

During the processing of verbs, readers form internal representations of the events described by those verbs. Two key elements in the construction of event representations are temporal information, given by the verbs that describe the represented events, and the visual perspective from which the events are represented. The current study is composed of two experiments aimed at examining the roles these two factors play in event representation. Specifically, the study aimed to determine how temporal information and visual perspective are represented during event imagination.

Experiment 1 investigated the role of temporal information associated with verbs, given by grammatical aspect (GA) …

Quantifying Cognitive Function In Concussed Athletes Before And After Acute Exercise Using A Choice Reaction Time Task, Stephanie A. Ramautar M.Sc., Michael E. Cinelli Ph.D.

Theses and Dissertations (Comprehensive)

Following a concussion, cognitive deficits have been shown to last longer than symptom resolution. Currently clinicians rely heavily on symptom emergence following the fundamental exercises of the return to play (RTP) protocol, which may leave athletes at risk of returning to play too early if cognitive deficits have not been detected. The purpose of this study was to assess the effects of exercise on choice reaction time (CRT) both at rest and following an acute exercise in 3 populations: non-concussed (NC), recently concussed (RC), and post-concussion syndrome (PCS) individuals. A CRT task in the form of an iPad application measured …

A Bittersweet Investigation Of Availability And Nutritive Value As Determinants Of Volitional Sucrose Consumption, Milan D. Valyear

Theses and Dissertations (Comprehensive)

Rats given ~24 h access to a 4% sucrose solution every 3^rd day (E3DA) consume about 100 g more solution than rats with continuous, everyday access (EDA). Under the same EDA-E3DA conditions rats will consume similar amounts of a more concentrated 8 or 16% sucrose solutions (Eikelboom, Hewitt, & Adams, Unpublished). It maybe that with these more concentrated solutions rats hit a satiety limit that prevents a difference between EDA and E3DA consumption from being evident. Experiment 1 was conducted to investigate the effect of adding quinine to 4% and 8% sucrose solutions with the intention of reducing consumption …

Recovery From Acute Toluene Intoxication Is Facilitated By The Nmda Receptor Co-Agonist D-Serine, But Not The Gabaa Receptor Antagonist Picrotoxin, Susan R. Samuel-Herter

Theses and Dissertations (Comprehensive)

Toluene is a volatile solvent found in many household products and when intentionally inhaled results in intoxication. In rats, acute inhalation of toluene results in sedation and neurological impairments, with marked increases in ambulation and vertical behaviour during the recovery period. Previous in vitro research has shown that toluene may exert its effects by inhibiting NMDA receptors, and / or by activating GABA_A receptors. To test whether modulation of these receptors are also implicated in the changes in motor behaviour and neurological impairments resulting from toluene vapour inhalation, rats were injected with the NMDA receptor co-agonist D-serine (1000 mg/kg …

Characterization Of The Transporter Protein Sodium-Potassium Adenosine Triphosphatase In The Myelin Membrane, Dara E C Schaefer

Theses and Dissertations (Comprehensive)

Sodium-potassium adenosine triphosphatase (Na⁺/K⁺-ATPase) is an integral membrane protein with known involvement in the maintenance of resting membrane potentials, nutrient uptake, cellular signal transduction, and cell-cell adhesion. The functional enzyme contains a catalytic alpha subunit and a glycosylated beta subunit, of which three isoforms of each are known to exist in the central nervous system (CNS). Altered expression and/or activity of Na⁺/K⁺-ATPase subunit isoforms has been previously implicated in the pathophysiology of several neurological disorders. This study characterized Na⁺/K⁺-ATPase expression and distribution in the myelin membrane, identified its …

Psychotherapy And The Embodiment Of The Neuronal Identity: A Hermeneutic Study Of Louis Cozolino's (2010) The Neuroscience Of Psychotherapy: Healing The Social Brain , Ari Simon Natinsky

Antioch University Dissertations & Theses

In recent years, there have been several ways in which researchers have attempted to integrate psychotherapy and neuroscience research. Neuroscience has been proposed as a method of addressing lingering questions about how best to integrate psychotherapy theories and explain their efficacy. For example, some psychotherapy outcome studies have included neuroimaging of participants in order to propose neurobiological bases of effective psychological interventions (e.g., Paquette et al., 2003). Other theorists have used cognitive neuroscience research to suggest neurobiological correlates of various psychotherapy theories and concepts (e.g., Schore, 2012). These efforts seem to embody broader historical trends, including the hope that neuroscience …

Genetic Algorithm With Logistic Regression For Prediction Of Progression To Alzheimer's Disease, Piers Johnson, Luke Vandewater, William Wilson, Paul Maruff, Greg Savage, Petra Graham, Lance S. Macaulay, Kathryn A. Ellis, Cassandra Szoeke, Ralph N. Martins, Christopher Rowe, Colin L. Masters, David Ames, Ping Zhang

Research outputs 2014 to 2021

Assessment of risk and early diagnosis of Alzheimer's disease (AD) is a key to its prevention or slowing the progression of the disease. Previous research on risk factors for AD typically utilizes statistical comparison tests or stepwise selection with regression models. Outcomes of these methods tend to emphasize single risk factors rather than a combination of risk factors. However, a combination of factors, rather than any one alone, is likely to affect disease development. Genetic algorithms (GA) can be useful and efficient for searching a combination of variables for the best achievement (eg. accuracy of diagnosis), especially when the search …