Neurosciences Commons^™

Adolescence, Alcohol, And Astrocytes: The Impact Of Adolescent Alcohol Use On Astrocyte-Synaptic Interactions, Structure, Function, And Behavior, Christopher Douglas Walker

Theses, Dissertations and Capstones

Alcohol is the third leading cause of preventable death in the United States and has substantial social and economic burdens. Excessive alcohol consumption in the form of binge drinking is highly prevalent among adolescents and emerging adults. Binge drinking is a form of excessive drinking, defined as consuming enough alcohol on a single occasion to result in blood alcohol concentrations above 0.08%. Approximately 55% of full-time college students aged 18- 22 years old have reported consuming alcohol in a binge manner. Furthermore, studies have shown that approximately 20% of college students meet the criteria for an alcohol use disorder (AUD). …

The Effects Of Astrocytic Derived Insulin-Like Growth Factor (Igf-1) On Cognition And Astrocytes, Destiny Wilson

Honors Theses

Insulin-like growth factor 1 (IGF-1) is a neuroendocrine signaling hormone that plays a vital role in growth and development, as well as learning and memory. Inhibition of this hormone results in cognitive impairments like those seen with age-related decline. While a majority of research has focused on the role of IGF-1 on neurons, the role of astrocytes still needs to be explored. Our research investigates how astrocytes and cognition are affected as a result of direct regulation of localized IGF-1 production in early development and after puberty. Preliminary studies in our laboratory established a connection between IGF-1 and glial fibrillary …

Sex Differences In Hippocampal O-Glcnacylation Of The Adult Mouse Brain, Makenzie Johnson

Selected Honors Theses

The hippocampus is a structure in the brain crucial for learning and memory. This occurs by synaptic remodeling known as long term potentiation and long term depression. Modifications of proteins in the hippocampus can affect its function. One of these modifications is the addition of O-linked β-N-acetylglucosamine, also known as O-GlcNAc. This is a sugar produced from glucose by the hexosamine biosynthetic pathway that is reversibly added onto serine and threonine residues of proteins by O-GlcNAc Transferase, or OGT. It is reversibly removed from these residues by O-GlcNAcAse, or OGA. This modification has been implicated in diabetes, cardiac dysfunction, and …

Chronic Effects Of Methylphenidate On Neuronal Viability And Plasticity, Hannah Oakes

Electronic Theses and Dissertations

Methylphenidate (MPH) is the most commonly prescribed drug to treat Attention Deficit Hyperactivity Disorder (ADHD). ADHD is now considered a life-long disorder; therefore, patients take MPH from adolescence into adulthood, highlighting the need for research studying chronic MPH use. MPH increases dopamine and norepinephrine within the synaptic cleft; therefore, chronic use of MPH may lead to changes within important dopaminergic pathways. One pathway, the mesolimbic pathway, includes the hippocampus, an area where adult neurogenesis occurs. We investigated the effects of chronic low and high doses of MPH on neurogenesis and examined levels of a few key proteins linked to cell …

Age Differences In Hippocampal Glutamate Modulation During Associative Learning And Memory: A Proton Functional Magnetic Resonance Spectroscopy (1h Fmrs) Study, Chaitali Anand

Wayne State University Dissertations

Episodic and associative memory decline is one of the earliest cognitive impairments in normal aging and among the defining cognitive features of Alzheimer’s disease (AD). Since, age-related cognitive decline gradually devolves into AD, with neuropathology preceding cognitive changes by many years, the identification of biomarkers of early disease progression is crucial. Reduction in glutamate, the main excitatory neurotransmitter involved in associative memory, in key brain regions such as the hippocampus, has been theorized as one of the cellular mechanisms underlying cognitive decline in aging and AD. A few neuroimaging studies that demonstrated a link between older adults’ weaker cognitive performance …

The Role Of Medial Septum Cholinergic Function In Processing Self-Movement Cues To Maintain Spatial Orientation, Jenna Rae Osterlund

Graduate Research Theses & Dissertations

Wandering is the most life-threatening and commonly reported symptom of Alzheimer’s Disease (AD), a neurodegenerative disorder characterized by an inability to maintain spatial orientation. The often deadly consequences of wandering are projected to rise in the coming decades due to the advancing aged population. These upcoming challenges necessitate a more comprehensive understanding of the neurobiology of spatial orientation in order to evaluate novel therapeutic techniques for symptoms such as wandering. The inability to maintain spatial orientation in AD may be due to the pathological degeneration of the hippocampal cholinergic system. This neurological system is conserved across species for its function …

Changes In Hippocampal-Anterior Cingulate Cortex Interactions During Remote Memory Recall, Ryan A. Wirt

UNLV Theses, Dissertations, Professional Papers, and Capstones

Spatial memory is an important cognitive process that relies on extensive neural networks throughout the brain. The hippocampus (HC) is important for the formation of these memories but over time, in a process referred to as consolidation, recall becomes increasingly reliant on other brain areas. The anterior cingulate cortex (ACC), a region within the medial prefrontal cortex, is important for spatial learning, spatial working memory, and remote memory recall, but the mechanisms underlying recall processes are still unknown. To better understand the role of the ACC and HC during memory recall, we introduced rodents into a series of spatially and …

Characterizing The Development Of Episodic Memory And Assessing The Reliability Of Fmri Measures, Lingfei Tang

Wayne State University Dissertations

The ability to remember past events is critical for everyday life and showed robust improvement over development from childhood to adulthood. With advances in noninvasive neuroimaging methods such as functional MRI in recent years, research efforts have been focused on identifying neural correlates underpinning developmental gains in memory performance. In my dissertation work, using a widely-validated subsequent memory paradigm, I aim to characterize functional MRI correlates of memory development. Specifically, I focused my investigation on identifying age differences in the functional patterns of two brain regions critical for memory, the prefrontal cortex and the hippocampus. Focusing on the prefrontal cortex …

Defining The Radioresponse Of Mossy Cells, Devon Ivy

Electronic Theses, Projects, and Dissertations

Clinical radiotherapy is used to treat a variety of brain tumors within the central nervous system. While effective, it can result in progressive and debilitating cognitive impairment that can diminish quality of life. These impairments have been linked to hippocampal dysfunction and corresponding deficits in spatial learning and memory. Mossy cells are a major population of excitatory neurons located within the dentate hilus and highly involved in hippocampal circuitry. They play critical roles in spatial navigation, neurogenesis, memory, and are particularly vulnerable to a variety of neurotoxic insults. However, their sensitivity to ionizing radiation has yet to be investigated in …

Multi-Scale Spatial Cognition Models And Bio-Inspired Robot Navigation, Martin I. Llofriu Alonso

USF Tampa Graduate Theses and Dissertations

The rodent navigation system has been the focus of study for over a century. Discoveries made lately have provided insight on the inner workings of this system. Since then, computational approaches have been used to test hypothesis, as well as to improve robotics navigation and learning by taking inspiration on the rodent navigation system.

This dissertation focuses on the study of the multi-scale representation of the rat’s current location found in the rat hippocampus. It first introduces a model that uses these different scales in the Morris maze task to show their advantages. The generalization power of larger scales of …

An Analysis Of Virtual Place Learning/Navigation In Children And Young Adults Prenatally Exposed To Alcohol, Neil Christopher Dodge

Wayne State University Dissertations

Fetal alcohol spectrum disorder refers to the spectrum of disorders resulting from prenatal alcohol exposure and is the leading cause of preventable mental retardation. Rodent studies have found that prenatal alcohol exposure impairs performance on the Morris water maze. This task requires the rodent to use distal room cues to locate a hidden platform in a pool of opaque water. Successful performance on this task is dependent upon hippocampal function. Rodents prenatally exposed to alcohol are impaired on the Morris water maze and show damage to hippocampal neurons. A human analogue of the Morris water maze, the virtual water maze …

Quantitative Mri Correlates Of Hippocampal And Neocortical Pathology In Intractable Temporal Lobe Epilepsy, Maged Goubran

Electronic Thesis and Dissertation Repository

Intractable or drug-resistant epilepsy occurs in over 30% of epilepsy patients, with many of these patients undergoing surgical excision of the affected brain region to achieve seizure control. Advances in MRI have the potential to improve surgical treatment of epilepsy through improved identification and delineation of lesions. However, validation is currently needed to investigate histopathological correlates of these new imaging techniques. The purpose of this work is to investigate histopathological correlates of quantitative relaxometry and DTI from hippocampal and neocortical specimens of intractable TLE patients. To achieve this goal I developed and evaluated a pipeline for histology to in-vivo MRI …

Predator-Based Fear Conditioning: A Novel Approach To The Study Of The Neurobiology Of Memory, Joshua D. Halonen

USF Tampa Graduate Theses and Dissertations

This series of experiments developed novel paradigms involving the integration of conventional and ethologically relevant forms of reinforcement in the study of fear conditioning in rats. Experiment 1 compared the effects of foot shock, immobilization and predator exposure, alone and in combination, on the expression of conditioned fear memory and extinction. The combination of all 3 reinforcers produced a significantly stronger fear memory and greater resistance to extinction, compared to when each reinforcer was administered alone. Furthermore, whereas conditioning with foot shock, alone, resulted in rapid extinction of the fear memory, the combination of immobilization and cat exposure, or all …

Efficacy Of Increased Ube3a Protein Levels In The Brain In Rescuing The Phenotype Of An Angelman Syndrome Mouse, Jennifer L. Daily

USF Tampa Graduate Theses and Dissertations

Angelman syndrome (AS), a genetic disorder occurring in approximately one in every 15,000 births, is characterized by severe mental retardation, seizures, difficulty speaking and ataxia. The gene responsible for AS was discovered to be UBE3A and encodes an E6-AP ubiquitin ligase. A unique feature of this gene is that it undergoes maternal imprinting in a neuron-specific manner. In the majority of AS cases, there is a mutation or deletion in the maternally inherited UBE3A gene, although other cases are the result of uniparental disomy or mismethylation of the maternal gene. While most human disorders characterized by severe mental retardation involve …

The Effects Of Pten Deletion On Cell Size And Plasticity In The Hippocampus, Margaret Sperow

Theses and Dissertations (ETD)

The tumor suppressor phosphatase and tensin homolog (PTEN) is the central negative regulator of the phosphatidylinositol 3-kinase (PI3K) -signaling pathway, which mediates diverse processes in various tissues. In the nervous system, the PI3K pathway modulates proliferation, migration, cellular size and synaptic transmission and plasticity. Neurologic abnormalities such as autism, seizures, and ataxia are associated with inherited PTEN mutations. Yet, how PTEN loss contributes to neurologic dysfunction remains unknown. PTEN loss during early development is associated with extensive deficits in neuronal migration and substantial hypotrophy of neurons and synaptic densities. However, whether its effect on synaptic transmission and plasticity is direct …

Torsina And The Pathophysiology Of Dyt1 Dystonia, Yu Zhao

Theses and Dissertations (ETD)

The goal of my dissertation work was to examine the systems biology of torsinA, a DYT1 dystonia-associated protein, by using rodent model systems. TorsinA is a putative ATPase associated with a variety of cellular activities (AAA+). Deletion of glutamic acid residue 302/303 in TOR1A is causally associated with many cases of early-onset primary dystonia.

In our work, transient forebrain ischemia and sciatic nerve transection were used as central and peripheral neural perturbations, respectively, to gain insight into the in vivo role(s) of torsinA. Moreover, transgenic mouse models that overexpress either human mutant torsinA (hMT) or wild-type torsinA (hWT) were used …