Neuroscience and Neurobiology Commons^™

Intracellular Mechanisms Associated With Cocaine Induced Conditioned Place Preference, Stephanie K. Nygard

Dissertations, Theses, and Capstone Projects

The aim of this dissertation was to investigate the intracellular responses associated with the acquisition and expression of cocaine-context associations. ERK (extracellular regulated kinase), CREB (cAMP responsive element binding protein), FosB and deltaFosB proteins were of particular interest due to their involvement in cocaine reward and in synaptic plasticity underlying learning and memory. We used the conditioned place preference (CPP) paradigm, which employs a Pavlovian conditioning procedure to establish an association between a drug-paired environment and the drug's rewarding effects, to study the role of these signaling pathways in cocaine-context associations. N-methyl-D-aspartate receptor (NMDAR) antagonism prior to cocaine administration during …

On The Role Of Neuronal Oscillations In Auditory Cortical Processing, Monica Noelle O'Connell

Dissertations, Theses, and Capstone Projects

Although it has been over 100 years since William James stated that "everyone knows what attention is", its underlying neural mechanisms are still being debated today. The goal of this research was to describe the physiological mechanisms of auditory attention using direct electrophysiological recordings in macaque primary auditory cortex (A1). A major focus of my research was on the role ongoing neuronal oscillations play in attentional modulation of auditory responses in A1.

For all studies, laminar profiles of synaptic activity, (indexed by current source density analysis) and concomitant firing patterns in local neurons (multiunit activity) were acquired simultaneously via linear …

Neurophysiological Bases Of Frequency Discrimination In Children With Auditory Processing Disorder Or Specific Language Impairment, Christine Rota-Donahue

Dissertations, Theses, and Capstone Projects

The purpose of this study was to determine if 10-12 year old children with Auditory Processing Disorder (APD) or Specific Language Impairment (SLI) could discriminate three different frequency changes behaviorally and electrophysiologically. Behavioral frequency discrimination and event-related potentials were examined using a 1000Hz pure tone base frequency. Typically developing children and children with APD or SLI differed in in their detection of frequency changes: behavioral results were below chance level and the MMN amplitude was smaller in the impaired population. Slight differences between children with APD and children with SLI were also found that might shed light on the controversy …

Neuroimmune Crosstalk: A Role For Neuropeptide Y In Inflammatory Bowel Disease, Henry H. Ruiz

Dissertations, Theses, and Capstone Projects

Neuropeptide Y (NPY) is a 36-amino acid peptide widely expressed in the central and peripheral nervous systems. In addition to other cells, NPY is also synthesized and co-released from sympathetic nerve fibers functioning as a potent sympathetic neuromodulator. NPY has been implicated in playing important roles in the regulation of energy balance, appetite, anxiety, vascular tone, and immune cell functioning. In addition, immune cells of both the innate and adaptive immune systems express functional NPY receptors. Some immune cells can produce and secrete NPY, and genetic alteration of these receptors results in altered immune cell functioning. Its direct association with …

Quantitative Evaluation Of Microglial Activation And Vascularization In Suicide, Tatiana Pavlovna Schnieder

Dissertations, Theses, and Capstone Projects

Accumulated evidence points to immunological factors in psychiatric disorders. In a variety of chronic neurological disorders, exacerbation is associated with inflammation and a loss of integrity of the blood-brain barrier. Microglia, the principal brain immunological cells in the healthy state, respond to changes in the internal environment of the brain through a sequence of activated states. This study compared microglial phenotypes in the white matter of autopsy brains from 11 suicide victims and 25 subjects who died involuntarily. Both groups included cases with and without major psychiatric disorders, which were determined by PA interviews. Cases were matched for sex, age, …

The Developmental Trajectory Of Contour Integration In Autism Spectrum Disorders, Ted S. Altschuler

Dissertations, Theses, and Capstone Projects

Sensory input is inherently ambiguous and complex, so perception is believed to be achieved by combining incoming sensory information with prior knowledge. One model envisions the grouping of sensory features (the local dimensions of stimuli) to be the outcome of a predictive process relying on prior experience (the global dimension of stimuli) to disambiguate possible configurations those elements could take. Contour integration, the linking of aligned but separate visual elements, is one example of perceptual grouping. Kanizsa-type illusory contour (IC) stimuli have been widely used to explore contour integration processing. Consisting of two conditions which differ only in the alignment …

The Neurodevelopment Of Basic Sensory Processing And Integration In Autism Spectrum Disorder, Alice Brown Brandwein

Dissertations, Theses, and Capstone Projects

This thesis presents three studies that together explore the neurophysiological basis for the sensory processing and integration abnormalities that have been observed in autism spectrum disorder (ASD) since the disorder was first described over half a century ago. In designing these studies we seek to fill a hole that currently exists in the research community‟s knowledge of the neurodevelopment of basic multisensory integration -- both in children with autism and as well as in those with typical development. The first study applied event related potentials (ERPs) and behavioral measures of multisensory integration to a large group of healthy participants ranging …

Using Otoacoustic Emissions To Evaluate Efferent Auditory Function In Humans, Simon Henin

Dissertations, Theses, and Capstone Projects

The auditory system continually adapts to changes in the acoustic environment over short periods of time. This fine-tuning of its dynamics is mediated in part by the medial olivocochlear (MOC) bundle, a neural feedback loop which aids in the regulation of cochlear micro-mechanics. The ability to measure the response of the MOC system in humans may provide significant insight into unique cochlear functions, such as its sharp frequency selectivity and wide dynamic range. In humans the efferent system can be investigated non-invasively using otoacoustic emissions (OAEs). However, how OAEs can best be used to evaluate efferent function, the pitfalls associated …