Neurosciences Commons^™

Frequency-Specificity And Pattern-Specificity Of The Buildup Of Auditory Stream Segregation, David Michael Weintraub

UNLV Theses, Dissertations, Professional Papers, and Capstones

During repeating sequences of low (A) and high (B) tones in an "...ABAB..." pattern, the likelihood of hearing two separate streams ("streaming") increases with more repetitions of the patterns, a phenomenon referred to as "buildup". Previous studies have shown that buildup is frequency specific (Anstis & Saida, 1985) and that its biasing effects decays over several seconds (Beauvois & Meddis, 1997). No study has examined whether the frequency specificity of buildup persists for such a long duration. To address these issues, Experiment 1 tested the decay of frequency-specific and non-frequency specific buildup. The results revealed that (1) frequency-specific buildup effects …

Interactions Among Positions In The Third And Fourth Membrane-Associated Domains At The Intersubunit Interface Of The N-Methyl-D-Aspartate Receptor Forming Sites Of Alcohol Action, Hong Ren, Yulin Zhao, Donard S. Dwyer, Robert W. Peoples

Biomedical Sciences Faculty Research and Publications

The N-methyl-d-aspartate (NMDA) glutamate receptor is a major target of ethanol in the brain. Previous studies have identified positions in the third and fourth membrane-associated (M) domains of the NMDA receptor GluN1 and GluN2A subunits that influence alcohol sensitivity. The predicted structure of the NMDA receptor, based on that of the related GluA2 subunit, indicates a close apposition of the alcohol-sensitive positions in M3 and M4 between the two subunit types. We tested the hypothesis that these positions interact to regulate receptor kinetics and ethanol sensitivity by using dual substitution mutants. In single-substitution mutants, we found that a position …

Exploring Picture Word Priming Effects In Healthy Aging Adults Using Event Related Potentials, Sasha C. Christopher

USF Tampa Graduate Theses and Dissertations

Objective: The aim of the present study was to investigate the mechanics with which older adults activate and access different subdomains of their mental lexicons during word retrieval for picture naming.

Method: Data were analyzed for 12 aging, native English speakers who performed a picture-word priming task. The auditory probe words were presented in the following conditions in relation to the picture stimuli: Identically related, strongly semantically related, weakly semantically related, strongly phonologically related, weakly phonologically related, semantically related to the strong phonological relative of the target picture label, or phonologically-related to the strong semantic relative of the target picture …

Visualizing Spatiotemporal Dynamics Of Apoptosis After G1 Arrest By Human T Cell Leukemia Virus Type 1 Tax And Insights Into Gene Expression Changes Using Microarray-Based Gene Expression Analysis., Mariluz Araínga, Hironobu Murakami, Yoko Aida

Journal Articles: Pharmacology & Experimental Neuroscience

BACKGROUND: Human T cell leukemia virus type 1 (HTLV-1) Tax is a potent activator of viral and cellular gene expression that interacts with a number of cellular proteins. Many reports show that Tax is capable of regulating cell cycle progression and apoptosis both positively and negatively. However, it still remains to understand why the Tax oncoprotein induces cell cycle arrest and apoptosis, or whether Tax-induced apoptosis is dependent upon its ability to induce G1 arrest. The present study used time-lapse imaging to explore the spatiotemporal patterns of cell cycle dynamics in Tax-expressing HeLa cells containing the fluorescent ubiquitination-based cell cycle …

Antioxidant Rescue Of Nf1/Ras-Induced Myelin And Vasculature Dysfunction, Debra A. Mayes, Tilat A. Rizvi, Shyra J. Miller, Rachel Oberst, Anat Stemmer-Rachamimov, Nancy Ratner

Neuroscience, Cell Biology & Physiology Faculty Publications

No abstract provided.

Unique Features And Neuronal Properties In A Multisensory Cortex, W. Alex Foxworthy

Theses and Dissertations

UNIQUE FEAUTRES OF ORGANIZATION AND NEURONAL PROPERTIES IN A MULTISENSORY CORTEX Multisensory processing is a ubiquitous sensory effect that underlies a wide variety of behaviors, such as detection and orientation, as well as perceptual phenomena from speech comprehension to binding. Such multisensory perceptual effects are presumed to be based in cortex, especially within areas known to contain multisensory neurons. However, unlike their lower-level/primary sensory cortical counterparts, little is known about the connectional, functional and laminar organization of higher-level multisensory cortex. Therefore, to examine the fundamental features of neuronal processing and organization in the multisensory cortical area of the posterior parietal …

Toward A Working Theory Of Neurorhetorics, Jeffrey L. Honnold

USF Tampa Graduate Theses and Dissertations

This piece makes the claim that rhetoric is first philosophy--before philosophy, epistemology, ontology, or any other field--or that rhetoric is, at the least, on equal footing as these fields because:

empathy--and thusly the impulse for communication--is physiologically hardwired into humans; special distinctions between human and animal are largely artificial constructions, as is evidenced by neurosciences; "hard" science, in the form of neurosciences, is providing entrance points & opportunities for rhetoric to raise its status within the academy; and said neurosciences, in addition to empathy studies, have shown strong evidence supporting linguistic and evolutionary links between humans and other species, thereby …

Frecuencia De Leptospira Spp En Porcinos De Crianza Tecnificada Y De Traspatio Beneficiados En Dos Mataderos De Lima, Luis Anampa V., Hermelinda Rivera G., Nestor Falcon P., Mariluz Araínga, Mercy Ramirez V.

Journal Articles: Pharmacology & Experimental Neuroscience

The objective of this study was to determine the frequency of antibodies against Leptospira spp in pigs reared in five well-managed farms (n = 163) and from 11 backyard breeding (n = 133) owners in the valley Lima, Peru. Blood samples (n=296) were collected in two slaughterhouses for antibody detection against eight serovars of Leptospira by microaglutination test. The 85.8 ± 3.9% (254/296) of samples had antibodies against one or more serovars of Leptospira. . The 89.6 ± 4.7% (146/163) and 82.1 ± 6.5% (108/133) of samples from well-managed farms and from backyard breeding pigs showed antibodies against Leptospira spp. …

Greater Benefits Of Multisensory Integration During Complex Sensorimotor Transformations., Verena N Buchholz, Samanthi C Goonetilleke, W Pieter Medendorp, Brian D Corneil

Brain and Mind Institute Researchers' Publications

Multisensory integration enables rapid and accurate behavior. To orient in space, sensory information registered initially in different reference frames has to be integrated with the current postural information to produce an appropriate motor response. In some postures, multisensory integration requires convergence of sensory evidence across hemispheres, which would presumably lessen or hinder integration. Here, we examined orienting gaze shifts in humans to visual, tactile, or visuotactile stimuli when the hands were either in a default uncrossed posture or a crossed posture requiring convergence across hemispheres. Surprisingly, we observed the greatest benefits of multisensory integration in the crossed posture, as indexed …

Resting-State Connectivity Identifies Distinct Functional Networks In Macaque Cingulate Cortex., R Matthew Hutchison, Thilo Womelsdorf, Joseph S Gati, L Stan Leung, Ravi S Menon, Stefan Everling

Brain and Mind Institute Researchers' Publications

Subregions of the cingulate cortex represent prominent intersections in the structural networks of the primate brain. The relevance of the cingulate to the structure and dynamics of large-scale networks ultimately requires a link to functional connectivity. Here, we map fine-grained functional connectivity across the complete extent of the macaque (Macaca fascicularis) cingulate cortex and delineate subdivisions pertaining to distinct identifiable networks. In particular, we identified 4 primary networks representing the functional spectrum of the cingulate: somatomotor, attention-orienting, executive, and limbic. The cingulate nodes of these networks originated from separable subfields along the rostral-to-caudal axis and were characterized by positive and …

Nociceptive Neuropeptide Increases And Periorbital Allodynia In A Model Of Traumatic Brain Injury., Melanie B. Elliott, Michael L. Oshinsky, Peter S. Amenta, Olatilewa Awe, Jack I. Jallo

Department of Neurosurgery Faculty Papers

OBJECTIVE: This study tests the hypothesis that injury to the somatosensory cortex is associated with periorbital allodynia and increases in nociceptive neuropeptides in the brainstem in a mouse model of controlled cortical impact (CCI) injury.

METHODS: Male C57BL/6 mice received either CCI or craniotomy-only followed by weekly periorbital von Frey (mechanical) sensory testing for up to 28 days post-injury. Mice receiving an incision only and naïve mice were included as control groups. Changes in calcitonin gene-related peptide (CGRP) and substance P (SP) within the brainstem were determined using enzyme-linked immunosorbent assay and immunohistochemistry, respectively. Activation of ionized calcium-binding adaptor molecule-1-labeled …

Glutathione-Mediated Neuroprotection Against Methylmercury Neurotoxicity In Cortical Culture Is Dependent On Mrp1, Travis Rush, Xiaoqian Liu, Andrew B. Nowakowski, David H. Petering, Doug Lobner

Biomedical Sciences Faculty Research and Publications

Methylmercury (MeHg) exposure at high concentrations poses significant neurotoxic threat to humans worldwide. The present study investigated the mechanisms of glutathione-mediated attenuation of MeHg neurotoxicity in primary cortical culture. MeHg (5 μM) caused depletion of mono- and disulfide glutathione in neuronal, glial and mixed cultures. Supplementation with exogenous glutathione, specifically glutathione monoethyl ester (GSHME) protected against the MeHg induced neuronal death. MeHg caused increased reactive oxygen species (ROS) formation measured by dichlorodihydrofluorescein (DCF) fluorescence with an early increase at 30 min and a late increase at 6 h. This oxidative stress was prevented by the presence of either GSHME or …

Electronic Properties Of Memantine (Alzheimer's Disease) And Amantadine (Anti-Flu) Drugs, Kirsten Middleton, Guo-Ping Zhang, Thomas F. George

Symposium 2012

Alzheimer’s Disease is the 5th leading cause of death for Americans 65 and older Treatment The U.S. Food and Drug Administration Only five drugs approved that “temporarily slow worsening of symptoms for about six to 12 months.” Effective for only about half of all patients.

Effects Of Hyperthermia On Photochemical Internalization-Mediated Delivery Of Bleomycin, Christina Schlazer

UNLV Theses, Dissertations, Professional Papers, and Capstones

Standard treatment protocols for high-grade gliomas, such as glioblastoma multiforme (GBM), are highly ineffective due to their inability to eradicate infiltrating tumor cells. Improvements in overall survival are likely to be realized only with the development of more effective localized therapies capable of eradicating tumor cells in the surgical resection margin and beyond. Photochemical internalization (PCI) is a localized light-based therapeutic modality that enhances the efficacy of therapeutic macromolecules including chemotherapeutic agents such as bleomycin. A number of studies have shown that this photodynamic therapy (PDT) - based modality may prove effective in the treatment of high-grade gliomas.

Three-dimensional multicell …

A Pre-Clinical Assessment Of Minocycline For Treatment Of Chronic Neuropathic Pain After Spinal Cord Injury, Alissa R. Poteete

Dissertations and Theses (Open Access)

Patients living with a spinal cord injury (SCI) often develop chronic neuropathic pain (CNP). Unfortunately, the clinically approved, current standard of treatment, gabapentin, only provides temporary pain relief. This treatment can cause numerous adverse side effects that negatively affect the daily lives of SCI patients. There is a great need for alternative, effective treatments for SCI-dependent CNP.

Minocycline, an FDA-approved antibiotic, has been widely prescribed for the treatment of acne for several decades. However, recent studies demonstrate that minocycline has neuroprotective properties in several pre-clinical rodent models of CNS trauma and disease. Pre-clinical studies also show that short-term minocycline treatment …

Neocortical Layer 4 To Layer 2/3 Sensory Information Processing Investigated With Digital-Light-Projection Neuronal Photostimulation, Jason Paul Jerome

Theses and Dissertations (ETD)

The mammalian brain forms neuronal networks and microcircuits with cell-type- and anatomical-specific synaptic connections. Despite great advances in elucidating the cellular physiology of the nervous system, little is known about the computational processes occurring at the level of neuronal microcircuits. Much success has been reported in describing the synaptic input patterns of many brain regions and cell types using photostimulation systems; however, these systems are severely limited in their ability to study the integration of synaptic input from multiple synchronous or temporally correlated presynaptic locations. Here we describe a system that allows the generation of arbitrary 2-D stimulus patterns with …

Phenotypic And Electrophysiologic Characterization Of A Mouse Model Of Fragile X Syndrome, Snigdha Roy

Theses and Dissertations (ETD)

Fragile X syndrome (FXS) is the most common form of inherited mental retardation. It is caused by a mutation in the fragile X mental retardation (FMR1) gene on the X chromosome. Many children with FXS exhibit autistic behaviors and deficits in motor coordination including speech articulation deficits. The development of the FMR1 knockout (Fmr1 KO) mouse, in which the Fmr1 gene is inactivated, has provided an animal model that can be used to investigate underlying neuro-physiological mechanisms associated with FXS as well as to evaluate potential therapeutic treatments. In this study, quantitative behavioral assays were used, such as long term …

An Investigation Of The Role Of Gabab Ligands On Cued And Contextual Fear Conditioning, Chelcie F. Heaney

UNLV Theses, Dissertations, Professional Papers, and Capstones

GABA is the primary inhibitory neurotransmitter in the brain and mediates several processes, including learning and memory. Activating or inhibiting GABA receptors allows for the examination of the effects of altered GABAergic signaling on these processes. The two main receptors, GABAA and GABAB, each have a different mechanism of action when activated, thus they may contribute differentially to learning and memory. The metabotropic GABAB receptor responds with the activation of several intracellular signaling cascades, which provide long-lasting inhibitory effects that primarily mediate network function. Conversely, the GABAA receptor is an ion channel that contributes more immediate inhibitory effects through the …

Exercise-Induced Neuroprotection In A Hemiparkinsonian 6-Hydroxydopamine Rat Model, Merrill Russen Landers

UNLV Theses, Dissertations, Professional Papers, and Capstones

Outside of finding a cure, one of the preeminent goals of research in Parkinson's disease (PD) is finding a neuroprotective treatment that when applied prior to the onset of the disease will decrease the risk and severity of the subsequent disease. One such treatment that has potential as a neuroprotective agent in PD is exercise. Several studies have found forced exercise to be protective of Parkinson's disease in adult rodent models; however, few of these studies have used a design wherein voluntary exercise was evaluated. Moreover, no study has used a true neuroprotective design in which exercise was applied prior …

Effect Of Synthetic Aβ Peptide Oligomers And Fluorinated Solvents On Kv1.3 Channel Properties And Membrane Conductance, Maria I. Lioudyno, Matteo Broccio, Yuri Sokolov, Suhail Rasool, Jessica Wu, Michael T. Alkire, Virginia Liu, J. Ashot Kozak, Philip R. Dennison, Charles G. Glabe, Mathias Lösche, James E. Hall

Neuroscience, Cell Biology & Physiology Faculty Publications

The impact of synthetic amyloid β (1–42) (Aβ_1–42) oligomers on biophysical properties of voltage-gated potassium channels Kv 1.3 and lipid bilayer membranes (BLMs) was quantified for protocols using hexafluoroisopropanol (HFIP) or sodium hydroxide (NaOH) as solvents prior to initiating the oligomer formation. Regardless of the solvent used Aβ_1–42 samples contained oligomers that reacted with the conformation-specific antibodies A11 and OC and had similar size distributions as determined by dynamic light scattering. Patch-clamp recordings of the potassium currents showed that synthetic Aβ_1–42 oligomers accelerate the activation and inactivation kinetics of Kv 1.3 current with no significant effect …