Neuroscience and Neurobiology Commons^™

Neural Mechanisms Underlying The Perception Of Three-Dimensional Shape From Texture: Adaptation And Aftereffects, Carole Filangieri

Dissertations, Theses, and Capstone Projects

Input into the visual system is two-dimensional (2D) and yet we effortlessly perceive the world around us as three-dimensional (3D). How we are able to accurately extract 3D shape information from the 2D representations that fall on the retina remains largely unknown. Although much research has been conducted that investigates higher levels of form processing (i.e. face recognition), less is known about the mechanisms that underlie the perception of simple 3D shape. Previous studies in our lab have shown that our ability to perceive 3D shape from texture cues relies on the visibility of orientation flows -- patterns that run …

Physiological And Subjective Aspects Of Positive Mood In Relation To Executive Functioning: The Potential Moderating Role Of Personality, Luz Helena Ospina

Dissertations, Theses, and Capstone Projects

Positive affect has been demonstrated to improve aspects of cognition. However, recent studies reveal that positive affect may hinder the same cognitive processes, such as executive functioning, memory and creativity. These discrepant findings may be due to differing levels of physiological arousal, a component of the circumplex model of affect, which has been largely ignored in affective research. For example, one recent study suggests that positive valence coupled with varying levels of physiological arousal (i.e., low, moderate, and high) may differentially affect performance on tasks of verbal fluency and memory. Furthermore, one other explanation for these inconsistent findings may relate …

The Neurophysiology Of Intersensory Selective Attention And Task Switching, Jeremy W. Murphy

Dissertations, Theses, and Capstone Projects

Our ability to selectively attend to certain aspects of the world and ignore others is fundamental to our day-to-day lives. The need for selective attention stems from capacity limitations inherent in our perceptual and cognitive processing architecture. Because not every elemental piece of our environment can be fully processed in parallel, the nervous system must prioritize processing. This prioritization is generally referred to as selective attention. Meanwhile, we are faced with a world that is constantly in flux, such that we have to frequently shift our attention from one piece of the environment to another and from one task to …

Designer Receptors Enhance Memory In A Mouse Model Of Down Syndrome, Ashley M. Fortress, Eric D. Hamlett, Elena M. Vazey, Gary Aston-Jones, Wayne A. Cass, Heather A. Boger, Ann-Charlotte E. Granholm

Neuroscience Faculty Publications

Designer receptors exclusively activated by designer drugs (DREADDs) are novel and powerful tools to investigate discrete neuronal populations in the brain. We have used DREADDs to stimulate degenerating neurons in a Down syndrome (DS) model, Ts65Dn mice. Individuals with DS develop Alzheimer's disease (AD) neuropathology and have elevated risk for dementia starting in their 30s and 40s. Individuals with DS often exhibit working memory deficits coupled with degeneration of the locus coeruleus (LC) norepinephrine (NE) neurons. It is thought that LC degeneration precedes other AD-related neuronal loss, and LC noradrenergic integrity is important for executive function, working memory, and attention. …

Neuroinflammation And J2 Prostaglandins: Linking Impairment Of The Ubiquitin-Proteasome Pathway And Mitochondria To Neurodegeneration, Maria E. Figueiredo-Pereira, Patricia Rockwell, Thomas Schmidt-Glenewinkel, Peter Serrano

Publications and Research

The immune response of the CNS is a defense mechanism activated upon injury to initiate repair mechanisms while chronic over-activation of the CNS immune system (termed neuroinflammation) may exacerbate injury. The latter is implicated in a variety of neurological and neurodegenerative disorders such as Alzheimer and Parkinson diseases, amyotrophic lateral sclerosis, multiple sclerosis, traumatic brain injury, HIV dementia, and prion diseases. Cyclooxygenases (COX-1 and COX-2), which are key enzymes in the conversion of arachidonic acid into bioactive prostanoids, play a central role in the inflammatory cascade. J2 prostaglandins are endogenous toxic products of cyclooxygenases, and because their levels are significantly …

Spatial And Temporal Characteristics Of Error-Related Activity In The Human Brain, Maital Neta, Francis M. Miezin, Steven M. Nelson, Joseph W. Dubis, Nico U.F. Dosenbach, Bradley L. Schlaggar, Steven E. Petersen

Center for Brain, Biology, and Behavior: Faculty Publications

A number of studies have focused on the role of specific brain regions, such as the dorsal anterior cingulate cortex during trials on which participants make errors, whereas others have implicated a host of more widely distributed regions in the human brain. Previous work has proposed that there are multiple cognitive control networks, raising the question of whether error-related activity can be found in each of these networks. Thus, to examine error-related activity broadly, we conducted a meta-analysis consisting of 12 tasks that included both error and correct trials. These tasks varied by stimulus input (visual, auditory), response output (button …

Exposure To Kynurenic Acid During Adolescence Increases Sign-Tracking And Impairs Long-Term Potentiation In Adulthood, Nicole E. Deangeli, Travis P. Todd, Stephen E. Chang, Hermes H. Yeh, Pamela W. Yeh, David J. Bucci

Dartmouth Scholarship

Changes in brain reward systems are thought to contribute significantly to the cognitive and behavioral impairments of schizophrenia, as well as the propensity to develop co-occurring substance abuse disorders. Presently, there are few treatments for persons with a dual diagnosis and little is known about the neural substrates that underlie co-occurring schizophrenia and substance abuse. One goal of the present study was to determine if a change in the concentration of kynurenic acid (KYNA), a tryptophan metabolite that is increased in the brains of people with schizophrenia, affects reward-related behavior. KYNA is an endogenous antagonist of NMDA glutamate receptors and …

Data From: A Stochastic Burst Follows The Periodic Morning Peak In Individual Drosophila Locomotion, Stanislav Lazopulo, Juan A. Lopez, Paul Levy, Sheyum Syed

Physics Data Sets

The data is associated to the article A Stochastic Burst Follows the Periodic Morning Peak in Individual Drosophila Locomotion published in PLoS ONE. The full text article can be found at https://doi.org/10.1371/journal.pone.0140481

Developmental Remodeling Of Relay Cells In The Dorsal Lateral Geniculate Nucleus In The Absence Of Retinal Input, Rana N. El-Danaf, Thomas E. Krahe, Emily K. Dilger, Martha E. Bickford, Michael A. Fox, William Guido

Anatomy and Neurobiology Publications

Background

The dorsal lateral geniculate nucleus (dLGN) of the mouse has been an important experimental model for understanding thalamic circuit development. The developmental remodeling of retinal projections has been the primary focus, however much less is known about the maturation of their synaptic targets, the relay cells of the dLGN. Here we examined the growth and maturation of relay cells during the first few weeks of life and addressed whether early retinal innervation affects their development. To accomplish this we utilized themath5 null (math5−/−) mouse, a mutant lacking retinal ganglion cells and central projections.

Results

The …

Microglia Processes Associate With Diffusely Injured Axons Following Mild Traumatic Brain Injury In The Micro Pig, Audrey D. Lafrenaye, Masak Todani, Susan A. Walker, John T. Povlishock

Anatomy and Neurobiology Publications

Background

Mild traumatic brain injury (mTBI) is an all too common occurrence that exacts significant personal and societal costs. The pathophysiology of mTBI is complex, with reports routinely correlating diffuse axonal injury (DAI) with prolonged morbidity. Progressive chronic neuroinflammation has also recently been correlated to morbidity, however, the potential association between neuroinflammatory microglia and DAI is not well understood. The majority of studies exploring neuroinflammatory responses to TBI have focused on more chronic phases of injury involving phagocytosis associated with Wallerian change. Little, however, is known regarding the neuroinflammatory response seen acutely following diffuse mTBI and its potential relationship to …

Acetylcholine Release In Mouse Hippocampal Ca1 Preferentially Activates Inhibitory-Selective Interneurons Via Α4Β2* Nicotinic Receptor Activation, L. Andrew Bell, Karen A. Bell, A. Rory Mcquiston

Anatomy and Neurobiology Publications

Acetylcholine (ACh) release onto nicotinic receptors directly activates subsets of inhibitory interneurons in hippocampal CA1. However, the specific interneurons activated and their effect on the hippocampal network is not completely understood. Therefore, we investigated subsets of hippocampal CA1 interneurons that respond to ACh release through the activation of nicotinic receptors and the potential downstream effects this may have on hippocampal CA1 network function. ACh was optogenetically released in mouse hippocampal slices by expressing the excitatory optogenetic protein oChIEF-tdTomato in medial septum/diagonal band of Broca cholinergic neurons using Cre recombinase-dependent adeno-associated viral mediated transfection. The actions of optogenetically released ACh were …

Proteomics: In Pursuit Of Effective Traumatic Brain Injury Therapeutics, Pavel N. Lizhnyak, Andrew K. Ottens

Anatomy and Neurobiology Publications

Effective traumatic brain injury (TBI) therapeutics remain stubbornly elusive. Efforts in the field have been challenged by the heterogeneity of clinical TBI, with greater complexity among underlying molecular phenotypes than initially conceived. Future research must confront the multitude of factors comprising this heterogeneity, representing a big data challenge befitting the coming informatics age. Proteomics is poised to serve a central role in prescriptive therapeutic development, as it offers an efficient endpoint within which to assess post-TBI biochemistry. We examine rationale for multifactor TBI proteomic studies and the particular importance of temporal profiling in defining biochemical sequences and guiding therapeutic development. …

Acetylcholine Release In Mouse Hippocampal Ca1 Preferentially Activates Inhibitory-Selective Interneurons Via Α4Β2* Nicotinic Receptor Activation, L. Andrew Bell, Karen A. Bell, A. Rory Mcquiston

Anatomy and Neurobiology Publications

Acetylcholine (ACh) release onto nicotinic receptors directly activates subsets of inhibitory interneurons in hippocampal CA1. However, the specific interneurons activated and their effect on the hippocampal network is not completely understood. Therefore, we investigated subsets of hippocampal CA1 interneurons that respond to ACh release through the activation of nicotinic receptors and the potential downstream effects this may have on hippocampal CA1 network function. ACh was optogenetically released in mouse hippocampal slices by expressing the excitatory optogenetic protein oChIEF-tdTomato in medial septum/diagonal band of Broca cholinergic neurons using Cre recombinase-dependent adeno-associated viral mediated transfection. The actions of optogenetically released ACh were …

Gabaergic Regulation Of Cerebellar Ng2-Cell Development Is Altered In Perinatal White Matter Injury, Marzieh Zonouzi, Joseph Scafidi, Peijun Li, Brian Mcellin, Jorge Edwards, Jeffrey L. Dupree, Lloyd Harvey, Dandan Sun, Christian A. Hübner, Stuart G. Cull-Candy, Mark Farrant, Vittorio Gallo

Anatomy and Neurobiology Publications

Diffuse white matter injury (DWMI), a leading cause of neurodevelopmental disabilities in preterm infants, is characterized by reduced oligodendrocyte formation. Oligodendrocyte precursor cells (NG2-cells) are exposed to various extrinsic regulatory signals, including the neurotransmitter GABA. We investigated GABAergic signaling to cerebellar white matter NG2-cells in a mouse model of DWMI (chronic neonatal hypoxia). We found that hypoxia caused a loss of GABAA receptor-mediated synaptic input to NG2-cells, extensive proliferation of these cells and delayed oligodendrocyte maturation, leading to dysmyelination. Treatment of control mice with a GABAA receptor antagonist or deletion of the chloride-accumulating transporter NKCC1 mimicked the effects of hypoxia. …

"And If Your Friends Jumped Off A Bridge, Would You Do It Too?": How Developmental Neuroscience Can Inform Legal Regimes Governing Adolescents, Michael N. Tennison, Amanda C. Pustilnik

Faculty Scholarship

Legal models of adolescent autonomy and responsibility in various domains of law span a spectrum from categorical prohibitions of certain behaviors to recognitions of total adolescent autonomy. The piecemeal approach to the limited decision-making capacity of adolescents lacks an empirical foundation in the differences between adolescent and adult decision-making, leading to counterintuitive and inconsistent legal outcomes. The law limits adolescent autonomy with respect to some decisions that adolescents are perfectly competent to make, and in other areas, the law attributes adult responsibility and imposes adult punishments on adolescents for making decisions that implicate their unique volitional vulnerabilities. As developmental neuroscientists …

How Does The Brain Implement Adaptive Decision Making To Eat?, Valérie Compan, B. Timothy Walsh, Walter Kaye, Allan Geliebter

Lander College of Arts and Sciences Publications and Research

Adaptive decision making to eat is crucial for survival, but in anorexia nervosa, the brain persistently supports reduced food intake despite a growing need for energy. How the brain persists in reducing food intake, sometimes even to the point of death and despite the evolution of multiple mechanisms to ensure survival by governing adaptive eating behaviors, remains mysterious. Neural substrates belong to the reward-habit system, which could differ among the eating disorders. The present review provides an overview of neural circuitry of restrictive food choice, binge eating, and the contribution of specific serotonin receptors. One possibility is that restrictive food …

High Fat High Cholesterol Diet (Western Diet) Aggravates Atherosclerosis, Hyperglycemia And Renal Failure In Nephrectomized Ldl Receptor Knockout Mice: Role Of Intestine Derived Lipopolysaccharide, Siddhartha S. Ghosh, Samuel Righi, Richard Krieg, Le Kang, Daniel Carl, Jing Wang, H. Davis Massey, Domenic A. Sica, Todd W. B. Gehr, Shobha Ghosh

Anatomy and Neurobiology Publications

A high fat meal, frequently known as western diet (WD), exacerbates atherosclerosis and diabetes. Both these diseases are frequently associated with renal failure. Recent studies have shown that lipopolysaccharide (LPS) leaks into the circulation from the intestine in the setting of renal failure and after WD. However, it is not clear how renal function and associated disorders are affected by LPS. This study demonstrates that circulatory LPS exacerbates renal insufficiency, atherosclerosis and glucose intolerance. Renal insufficiency was induced by 2/3 nephrectomy in LDL receptor knockout mice. Nx animals were given normal diet (Nx) or WD (Nx+WD). The controls were sham …

Elucidating The Role Of Injury-Induced Electric Fields (Efs) In Regulating The Astrocytic Response To Injury In The Mammalian Central Nervous System, Matthew L. Baer, Scott C. Henderson, Raymond J. Colello

Anatomy and Neurobiology Publications

Injury to the vertebrate central nervous system (CNS) induces astrocytes to change their morphology, to increase their rate of proliferation, and to display directional migration to the injury site, all to facilitate repair. These astrocytic responses to injury occur in a clear temporal sequence and, by their intensity and duration, can have both beneficial and detrimental effects on the repair of damaged CNS tissue. Studies on highly regenerative tissues in non-mammalian vertebrates have demonstrated that the intensity of direct-current extracellular electric fields (EFs) at the injury site, which are 50–100 fold greater than in uninjured tissue, represent a potent signal …

The Effect Of Silver Nanoparticles On Synaptic Responses In The Lateral Giant Escape Circuit Of The Crayfish, Samantha N. Adkins

Theses, Dissertations and Capstones

The lateral giant neuron in the crayfish is a neuron that controls the reflexive escape response; the context and experience-dependent tuning of this response is critical for survival. Serotonin modulates synaptic responses in this neuron, and social experiences (stress) changes the modulatory role of serotonin. I investigated the mechanisms of induced synaptic response changes and serotonergic modulatory changes after silver nanoparticle exposure to ask if 1) contaminant induced stress changes serotonergic modulation in a manner consistent with social stress and 2) shed light on potential neurotoxic effects of widely used, but poorly understood nanomaterials. Our data show that stress induced …

Firing Rate Dynamics In Recurrent Spiking Neural Networks With Intrinsic And Network Heterogeneity, Cheng Ly

Statistical Sciences and Operations Research Publications

Heterogeneity of neural attributes has recently gained a lot of attention and is increasing recognized as a crucial feature in neural processing. Despite its importance, this physiological feature has traditionally been neglected in theoretical studies of cortical neural networks. Thus, there is still a lot unknown about the consequences of cellular and circuit heterogeneity in spiking neural networks. In particular, combining network or synaptic heterogeneity and intrinsic heterogeneity has yet to be considered systematically despite the fact that both are known to exist and likely have significant roles in neural network dynamics. In a canonical recurrent spiking neural network model, …

The Need For Theory To Guide Concussion Research, Dennis Molfese

Center for Brain, Biology, and Behavior: Faculty Publications

While the focus on concussion research has expanded greatly over the past decade, progress in identifying the mechanisms and consequences of head injury, the recovery path and the development of potential interventions to facilitate recovery have been largely absent. Instead, the field has largely progressed through an accumulation of data without the guidance of any systematic theory to guide the formulation of research questions or generate testable hypotheses. As part of this special issue on sports concussion, we advance a theory to describe the evolution of a neural network during the development of a cognitive process as well as the …

Resting-State Brain Connectivity After Surgical And Behavioral Weight Loss, Rebecca J. Lepping, Amanda S. Bruce, Alex Francisco, Hung-Wen Yeh, Laura E. Martin, Joshua N. Powell, Laura Hancock, Trisha M. Patrician, Florence J. Breslin, Niazy Selim, Joseph E. Donnelly, William M. Brooks, Cary R. Savage, W. Kyle Simmons, Jared M. Bruce

Center for Brain, Biology, and Behavior: Faculty Publications

Objective: Changes in food-cue neural reactivity associated with behavioral and surgical weight loss interventions have been reported. Resting functional connectivity represents tonic neural activity that may contribute to weight loss success. This study explores whether intervention type is associated with differences in functional connectivity after weight loss. Methods: Fifteen participants with obesity were recruited prior to adjustable gastric banding surgery. Thirteen demographically matched participants with obesity were selected from a separate behavioral diet intervention. Resting-state functional magnetic resonance imaging was collected 3 months after surgery/ behavioral intervention. ANOVA was used to examine post-weight loss differences between the two groups in …

Differences In Prefrontal Cortex Activation And Deactivation During Strategic Episodic Verbal Memory Encoding In Mild Cognitive Impairment, Joana B. Balardin, Marcelo C. Batistuzzo, Maria Da Graca Moraes Martin, Joao R. Sato, Jerusa Smid, Claudia Porto, Cary R. Savage, Ricardo Nitrini, Edson Amaro Jr., Eliane C. Miotto

Center for Brain, Biology, and Behavior: Faculty Publications

In this study we examined differences in fMRI activation and deactivation patterns during episodic verbal memory encoding between individuals with MCI (n = 18) and healthy controls (HCs) (n = 17). Participants were scanned in two different sessions during the application of self-initiated or directed instructions to apply semantic strategies at encoding of word lists. MCI participants showed reduced free recall scores when using self-initiated encoding strategies that were increased to baseline controls' level after directed instructions were provided. During directed strategic encoding, greater recruitment of frontoparietal regions was observed in both MCI and control groups; group differences …

Correlations Between Sensory Encoding And Central Morphology Of Muscle Proprioceptors In The Rat, Hanna Marie Gabriel

Browse all Theses and Dissertations

Until now, observations regarding the central morphology and organization of Ia, group II and Ib Golgi tendon organ afferents have been confined to the cat model. As the use of rodents in the study of the development and organization of segmental spinal cord circuitry increases, a complete account of the peripheral encoding and central connectivity of rodent muscle proprioceptors is necessary. The data presented in this study establish the central morphology and spatial distribution of 12 (4 of each class) functionally phenotyped muscle proprioceptor afferents in the rat by intracellular labeling with Neurobiotin. Each afferent type showed a characteristic central …

What, If Anything, Is Colored?: Color Perceptions - Color Judgments - Without Color, Olivia Ziegler

Philosophy Honors Papers

No abstract provided.

The Effects Of Molecular Chaperones On Tau Fibril Assembly, Ahmed Omran

Electronic Theses and Dissertations

The accumulation of microtubule-associated protein tau into fibrillar aggregates is the hallmark of Alzheimer’s disease and other neurodegenerative disorders, collectively referred to as tauopathies. Fibrils can propagate from one cell to the next and spread throughout the brain. However, a study shows that only small aggregates can be taken up by cultured neuronal cells. The mechanisms that lead to the breakage of fibrils into smaller fragments remain unknown. In yeast, the AAA+ chaperone HSP104 processes the reactivation of protein aggregates and is responsible for fragmentation of fibrils. This study focused on investigating the effects of molecular chaperones on tau fibrils …

Orbitofrontal 18f-Dopa Uptake And Movement Preparation In Parkinson’S Disease, Lucio Marinelli, Arnoldo Piccardo, Laura Mori, Silvia Morbelli, Nicola Girtler, Antonio Castaldi, Agnese Picco, Carlo Trompetto, Maria Felice Ghilardi, Giovanni Abbruzzese, Flavio Nobili

Publications and Research

In Parkinson’s disease (PD) degeneration of mesocortical dopaminergic projections may determine cognitive and behavioral symptoms. Choice reaction time task is related to attention, working memory, and goal-directed behavior. Such paradigm involves frontal cortical circuits receiving mesocortical dopamine which are affected early in PD. The aim of this study is to characterize the role of dopamine on the cognitive processes that precede movement in a reaction time paradigm in PD.We enrolled 16 newly diagnosed and untreated patientswith PDwithout cognitive impairment or depression and 10 control subjectswith essential tremor. They performed multiple-choice reaction time task with the right upper limb and brain …

Pcdh19 Expression In Normal And Regenerating Adult Zebrafish Retinas, Kristin N. Forkapa Ms.

Williams Honors College, Honors Research Projects

My Honors Research Project will test the function of the N-cadherin molecule on the zebrafish optic nerve regeneration. N-cadherin is a member of the cadherin superfamily. Cadherins are cell adhesion molecules important for animal development and maintenance of adult structures. Unlike mammals, fish and amphibians have the ability to regenerate their optic nerve after damages. Molecular mechanisms underlying the optic nerve regeneration are still under intense investigation. Studies in Dr. Liu’s laboratory showed that expression of several cadherins, including N-cadherin, was greatly increased during adult zebrafish optic nerve regeneration, suggesting that cadherins may be involved in the optic nerve regeneration …

Targeting Methylglyoxal And Ppar Gamma To Alleviate Neuropathic Pain Associated With Type 2 Diabetes, Ryan B. Griggs

Theses and Dissertations--Physiology

Neuropathic pain affects up to 50% of the 29 million diabetic patients in the United States. Neuropathic pain in diabetes manifests as a disease of the peripheral and central nervous systems. The prevalence of type 2 diabetes is far greater than type 1 (90%), yet the overwhelming focus on type 1 models this has left the mechanisms of pain in type 2 diabetes largely unknown. Therefore I aimed to improve the current mechanistic understanding of pain associated with type 2 diabetes using two preclinical rodent models: Zucker Diabetic Fatty rats and db/db mice. In addition, I highlight the translational importance …

Examining Oxytocin As A Potential Pharmacotherapy For Methamphetamine Addiction, Brittney M. Cox

MUSC Theses and Dissertations

Human and animal studies suggest that females differ in their motivation to use methamphetamine (meth), and have increased propensity to relapse. However, addiction pharmacotherapies have primarily only been tested in males, which may not accurately predict treatment outcomes in females. Evidence suggests that oxytocin, an endogenous peptide well known for its role in social behaviors and childbirth, is a promising addiction pharmacotherapy. This dissertation first examines sex differences in the effect of oxytocin to decrease meth and sucrose seeking. Our data indicate that systemic oxytocin decreased responding for meth differentially in males and females on a progressive ratio schedule of …