Neurosciences Commons^™

Multiple Subject Barycentric Discriminant Analysis (Musubada): How To Assign Scans To Categories Without Using Spatial Normalization, Hervé Abdi, Lynne J. Williams, Andrew C. Connolly, M. Ida Gobbini

Dartmouth Scholarship

We present a new discriminant analysis (DA) method called Multiple Subject Barycentric Discriminant Analysis (MUSUBADA) suited for analyzing fMRI data because it handles datasets with multiple participants that each provides different number of variables (i.e., voxels) that are themselves grouped into regions of interest (ROIs). Like DA, MUSUBADA (1) assigns observations to predefined categories, (2) gives factorial maps displaying observations and categories, and (3) optimally assigns observations to categories. MUSUBADA handles cases with more variables than observations and can project portions of the data table (e.g., subtables, which can represent participants or ROIs) on the factorial maps. Therefore MUSUBADA can …

Degeneration Of Phrenic Motor Neurons Induces Long-Term Diaphragm Deficits Following Mid-Cervical Spinal Contusion In Mice., Charles Nicaise, Rajarshi Putatunda, Tamara J Hala, Kathleen A Regan, David M Frank, Jean-Pierre Brion, Karelle Leroy, Roland Pochet, Megan C Wright, Angelo C Lepore

Department of Neuroscience Faculty Papers

A primary cause of morbidity and mortality following cervical spinal cord injury (SCI) is respiratory compromise, regardless of the level of trauma. In particular, SCI at mid-cervical regions targets degeneration of both descending bulbospinal respiratory axons and cell bodies of phrenic motor neurons, resulting in deficits in the function of the diaphragm, the primary muscle of inspiration. Contusion-type trauma to the cervical spinal cord is one of the most common forms of human SCI; however, few studies have evaluated mid-cervical contusion in animal models or characterized consequent histopathological and functional effects of degeneration of phrenic motor neuron-diaphragm circuitry. We have …

Diffuse Traumatic Axonal Injury Within The Visual System: Implications For Visual Pathway Reorganization, Jiaqiong Wang

Theses and Dissertations

Traumatic brain injury is a major health problem with much of its morbidity associated with traumatic axonal injury (TAI). To date, significant insight has been gained into the initiating pathogenesis of TAI. However, the specific anterograde and retrograde sequelae of TAI are poorly understood because the diffuse nature of TAI complicates data analysis. To overcome this limitation, we subjected transgenic mice expressing yellow fluorescent protein (YFP) within the visual system to central fluid percussion injury, and consistently generated diffuse TAI within the optic nerve that could easily be followed in the organized YFP positive fibers. We demonstrated progressive axonal swelling, …

Metabotropic Glutamate Receptor 5 In The Medial Prefrontal Cortex: Role In Cocaine Sensitization And Addiction, Kristin Marie Timmer

Theses and Dissertations (ETD)

Cocaine sensitization is associated with cocaine-induced hyperexcitability of pyramidal projection neurons within the medial prefrontal cortex (mPFC). Such hyperexcitability presumably results in increased glutamatergic input to reward-affiliated brain regions such as the ventral tegemental area (VTA) and nucleus accumbens (NAc), consequently facilitating drugseeking behavior. Metabotropic glutamate receptor 5 (mGluR5) has been implicated in cocaine addiction and demonstrated to increase neuronal excitability, therefore, the aim of the present study was to investigate the effect of intra-mPFC mGluR5 manipulation on behavioral and neurochemical sensitization and drug-seeking. Bilateral cannulae were implanted into the mPFC of male Sprague-Dawley rats and mGluR5 antagonist MTEP (15 …

How To Be Happy: An Interview With Kevin Corcoran, Kevin Corcoran, Evan Rosa

University Faculty Publications and Creative Works

No abstract provided.

Protocol For A Randomized Controlled Trial Evaluating The Effect Of Physical Activity On Delaying The Progression Of White Matter Changes On Mri In Older Adults With Memory Complaints And Mild Cognitive Impairment: The Aibl Active Trial, E V Cyarto, N T Lautenschlager, P M Desmond, D Ames, C Szoeke, O Salvado, Matthew Sharman, Kathryn A Ellis, P M Phal, C L Masters, C C Rowe, Ralph Martins, Kay L Cox

Research outputs 2012

Background: Older adults free of dementia but with subjective memory complaints (SMC) or mild cognitive impairment (MCI) are considered at increased risk of cognitive decline. Vascular risk factors (VRF), including hypertension, heart disease, smoking, hypercholesterolemia and lack of physical activity (PA) have been identified as modifiable risk factors contributing to cognitive decline, and white matter hyperintensities (WMH) are associated with VRF, SMC and cognitive impairment. Findings from a growing number of clinical trials with older adults are providing strong evidence for the benefits of physical activity for maintaining cognitive function, but few studies are investigating these benefits in high-risk populations. …

Algorithmic Decomposition Of Shuffle On Words, Franziska Biegler, Mark Daley, Ian Mcquillan

Brain and Mind Institute Researchers' Publications

We investigate shuffle-decomposability into two words. We give an algorithm which takes as input a DFA M (under certain conditions) and determines the unique candidate decomposition into words u and v such that L(M) = u v ifM is shuffle decomposable, in time O(|u| + |v|). Even though this algorithm does not determine whether or not the DFA is shuffle decomposable, the sublinear time complexity of only determining the two words under the assumption of decomposability is surprising given the complexity of shuffle, and demonstrates an interesting property of the operation. We also show that for given words u and …

Expanding The Basic Science Debate: The Role Of Physics Knowledge In Interpreting Clinical Findings., Mark Goldszmidt, John Paul Minda, Sarah L Devantier, Aimee L Skye, Nicole N Woods

Brain and Mind Institute Researchers' Publications

Current research suggests a role for biomedical knowledge in learning and retaining concepts related to medical diagnosis. However, learning may be influenced by other, non-biomedical knowledge. We explored this idea using an experimental design and examined the effects of causal knowledge on the learning, retention, and interpretation of medical information. Participants studied a handout about several respiratory disorders and how to interpret respiratory exam findings. The control group received the information in standard "textbook" format and the experimental group was presented with the same information as well as a causal explanation about how sound travels through lungs in both the …

Exosome-Mediated Shuttling Of Microrna-29 Regulates Hiv Tat And Morphine-Mediated Neuronal Dysfunction., Guoku Hu, H Yao, A D. Chaudhuri, Sowmya V. Yelamanchili, H Wen, P D. Cheney, Howard S. Fox, Shilpa J. Buch

Journal Articles: Pharmacology & Experimental Neuroscience

Neuronal damage is a hallmark feature of HIV-associated neurological disorders (HANDs). Opiate drug abuse accelerates the incidence and progression of HAND; however, the mechanisms underlying the potentiation of neuropathogenesis by these drugs remain elusive. Opiates such as morphine have been shown to enhance HIV transactivation protein Tat-mediated toxicity in both human neurons and neuroblastoma cells. In the present study, we demonstrate reduced expression of the tropic factor platelet-derived growth factor (PDGF)-B with a concomitant increase in miR-29b in the basal ganglia region of the brains of morphine-dependent simian immunodeficiency virus (SIV)-infected macaques compared with the SIV-infected controls. In vitro relevance …

Psychophysical And Neural Evidence For Emotion-Enhanced Perceptual Vividness, Rebecca M. Todd, Deborah Talmi, Taylor W. Schmitz, Josh Susskind, Adam K. Anderson

Brain and Mind Institute Researchers' Publications

Highly emotional events are associated with vivid "flashbulb" memories. Here we examine whether the flashbulb metaphor characterizes a previously unknown emotion-enhanced vividness (EEV) during initial perceptual experience. Using a magnitude estimation procedure, human observers estimated the relative magnitude of visual noise overlaid on scenes. After controlling for computational metrics of objective visual salience, emotional salience was associated with decreased noise, or heightened perceptual vividness, demonstrating EEV, which predicted later memory vividness. Event-related potentials revealed a posterior P2 component at ~200 ms that was associated with both increased emotional salience and decreased objective noise levels, consistent with EEV. Blood oxygenation level-dependent …

The Neural Substrates Of Complex Argument Structure Representations: Processing “Alternating Transitivity” Verbs, Aya Meltzer-Asscher, Julia Schuchard, Dirk B. Den Ouden, Cynthia K. Thompson

Communication Sciences and Disorders Faculty Articles and Research

This study examines the neural correlates of processing verbal entries with multiple argument structures using functional magnetic resonance imaging (fMRI). We compared brain activation in response to “alternating transitivity” verbs, corresponding to two different verbal alternates—one transitive and one intransitive—and simple verbs, with only one, intransitive, thematic grid. Fourteen young healthy participants performed a lexical decision task with the two verb types. Results showed significantly greater activation in the angular and supramarginal gyri (Brodmann areas (BAs) 39 and 40) extending to the posterior superior and middle temporal gyri bilaterally, for alternating compared to simple verbs. Additional activation was detected in …

Gonadotropin-Releasing Hormone Plasticity: A Comparative Perspective., T J Stevenson, T P Hahn, S A Macdougall-Shackleton, G F Ball

Brain and Mind Institute Researchers' Publications

Gonadotropin-releasing hormone 1 (GnRH1) is a key regulator of the reproductive neuroendocrine system in vertebrates. Recent developments have suggested that GnRH1 neurons exhibit far greater plasticity at the cellular and molecular levels than previously thought. Furthermore, there is growing evidence that sub-populations of GnRH1 neurons in the preoptic area are highly responsive to specific environmental and hormonal conditions. In this paper we discuss findings that reveal large variation in GnRH1 mRNA and protein expression that are regulated by social cues, photoperiod, and hormonal feedback. We draw upon studies using histochemistry and immediate early genes (e.g., c-FOS/ZENK) to illustrate that specific …

Perceptual Fluency Can Be Used As A Cue For Categorization Decisions., Sarah J Miles, John Paul Minda

Brain and Mind Institute Researchers' Publications

Learning in the prototype distortion task is thought to involve perceptual learning in which category members experience an enhanced visual response (Ashby & Maddox. Annual Review of Psychology, 56, 149-178, 2005). This response likely leads to more-efficient processing, which in turn may result in a feeling of perceptual fluency for category members. We examined the perceptual-fluency hypothesis by manipulating fluency independently from category membership. We predicted that when perceptual fluency was induced using subliminal priming, this fluency would be misattributed to category membership and would affect categorization decisions. In a prototype distortion task, the participants were more likely to judge …

Behavioral And Fmri Evidence That Cognitive Ability Modulates The Effect Of Semantic Context On Speech Intelligibility, Adriana A Zekveld, Mary Rudner, Ingrid Johnsrude, Dirk J Heslenfeld, Jerker Rönnberg

Brain and Mind Institute Researchers' Publications

Text cues facilitate the perception of spoken sentences to which they are semantically related (Zekveld, Rudner, et al., 2011). In this study, semantically related and unrelated cues preceding sentences evoked more activation in middle temporal gyrus (MTG) and inferior frontal gyrus (IFG) than nonword cues, regardless of acoustic quality (speech in noise or speech in quiet). Larger verbal working memory (WM) capacity (reading span) was associated with greater intelligibility benefit obtained from related cues, with less speech-related activation in the left superior temporal gyrus and left anterior IFG, and with more activation in right medial frontal cortex for related versus …

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.

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 …

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 …