Neuroscience and Neurobiology Commons^™

A Review On Locomotor Training After Spinal Cord Injury: Reorganization Of Spinal Neuronal Circuits And Recovery Of Motor Function, Andrew C. Smith, Maria Knikou

Publications and Research

Locomotor training is a classic rehabilitation approach utilized with the aim of improving sensorimotor function and walking ability in people with spinal cord injury (SCI). Recent studies have provided strong evidence that locomotor training of persons with clinically complete, motor complete, or motor incomplete SCI induces functional reorganization of spinal neuronal networks at multisegmental levels at rest and during assisted stepping. This neuronal reorganization coincides with improvements in motor function and decreased muscle cocontractions. In this review, we will discuss the manner in which spinal neuronal circuits are impaired and the evidence surrounding plasticity of neuronal activity after locomotor training …

Are Coloring Books Really Just For Kids? Investigating Possible Effects Of Specific Pattern Coloring On Conceptual, Physiological And Behavioral Aspects Of Anxiety, Hannah Taylor

Scripps Senior Theses

This study examined the role of specific pattern coloring, such as coloring books for adults, on conceptual, behavioral and physiological measures of anxiety. Undergraduate female students (n = 8) had ECG electrodes and a respiration belt attached and completed the State Trait Anxiety Inventory (STAI) at five time points; at baseline, after an initial autobiographical anxiety induction, following a passive relaxation condition, after a repeat induction and then after a coloring condition. The participants were randomly split into a control and experimental group; the control group free colored while the experimental group colored in a mandala pattern. Participants had the …

An Integrative Neurological Model For Basic Observable Human Behavior, Ryan M. Francis

Calvert Undergraduate Research Awards

The scientific method uncovers information from the natural world in small increments. This spurs the design of models to explain how the pieces fit together and to identify future targets of research. This is especially the case in psychology, where visualizing concepts is an advantageous practice. One all too common criticism of cognitive and behavioral models in psychology is the lack of a biological basis. This paper aims to alleviate part of this issue by integrating currently understood biological and neurological mechanisms that drive psychological phenomena into a predictive and descriptive model for basic human behavior. To accomplish this task, …

Melatonin Signaling Controls The Daily Rhythm In Blood Glucose Levels Independent Of Peripheral Clocks, Sharon Owino, Susana Contreras-Alcantara, Kenkichi Baba, Gianluca Tosini

Neuroscience: Faculty Publications

Melatonin is rhythmically secreted by both the pineal gland and retina in a circadian fashion, with its peak synthesis occurring during the night. Once synthesized, melatonin exerts its effects by binding to two specific G-protein coupled receptors-melatonin receptor type 1 (MT1) and melatonin receptor type 2(MT2). Recent studies suggest the involvement of MT1 and MT2 in the regulation of glucose homeostasis; however the ability of melatonin signaling to impart timing cues on glucose metabolism remains poorly understood. Here we report that the removal of MT1 or MT2 in mice abolishes the daily rhythm in blood glucose levels. Interestingly, removal of …

Altered Cerebellar Circuitry Following Thoracic Spinal Cord Injury In Adult Rats, Nishant P. Visavadiya, Joe E. Springer

Physical Medicine and Rehabilitation Faculty Publications

Cerebellar function is critical for coordinating movement and motor learning. However, events occurring in the cerebellum following spinal cord injury (SCI) have not been investigated in detail. We provide evidence of SCI-induced cerebellar synaptic changes involving a loss of granule cell parallel fiber input to distal regions of the Purkinje cell dendritic tree. This is accompanied by an apparent increase in synaptic contacts to Purkinje cell proximal dendrites, presumably from climbing fibers originating in the inferior olive. We also observed an early stage injury-induced decrease in the levels of cerebellin-1, a synaptic organizing molecule that is critical for establishing and …

The Effect Of Depth On Development And Sexual Dimorphism Of The Sonic System In Deep Sea Neobythitine Fishes: The Upper Continental Slope, Heba Ali

Theses and Dissertations

Abstract

Background: Cusk-eels from the subfamily Neobythiitinae are one of the major groups of sound-producing fishes on the continental slope. Sounds have never been recorded from a member of this subfamily, and sonic anatomy is considered a proxy for sound production. As the first part of a study on the effects of depth on sonic anatomy, we examined three relatively shallow species from the upper continental slope.

Methods: Three species (Hoplobrotula armata, Neobythites longipes and Neobythites unimaculatus) were examined for sonic anatomy (skeleton, swimbladder and sonic muscles), and sonic and epaxial muscle fibers were measured for diameter. …

Roles Of Planar Cell Polarity Proteins In Copa Axon Pathfinding, Ashley Morgan Purdy

Theses and Dissertations

In zebrafish, CoPA (Commissural Primary Ascending) is the first among ascending commissural axons to pathfind anteriorly and form the spinal commissure. One pathway that guides their anterior growth is the planar cell polarity (PCP) signaling pathway, but it is not fully known how PCP signaling regulates anterior guidance. We examined CoPA pathfinding in various PCP mutants to determine if anterior-posterior (A-P) guidance of CoPAs is dependent on PCP signaling. We found that certain PCP mutants exhibited anterior pathfinding defects, with approximately half of all affected CoPAs migrating incorrectly posteriorly. By using a translation-blocking DCC (Deleted in …

Cerebellar Nuclei Neurons Show Only Small Excitatory Responses To Optogenetic Olivary Stimulation In Transgenic Mice: In Vivo And In Vitro Studies, Huo Lu, Bo Yang, Dieter Jaeger

PCOM Scholarly Works

BACKGROUND: To study the olivary input to the cerebellar nuclei (CN) we used optogenetic stimulation in transgenic mice expressing channelrhodopsin-2 (ChR2) in olivary neurons. We obtained in vivo extracellular Purkinje cell (PC) and CN recordings in anesthetized mice while stimulating the contralateral inferior olive (IO) with a blue laser (single pulse, 10 - 50 ms duration). Peri-stimulus histograms were constructed to show the spike rate changes after optical stimulation. Among 29 CN neurons recorded, 15 showed a decrease in spike rate of variable strength and duration, and only 1 showed a transient spiking response. These results suggest that direct olivary …

Characterization Of A Putative Glycinergic Nigropallidal Pathway In The Rodent Brain, Rosalia Ortega

Open Access Theses & Dissertations

Glycinergic neurotransmission is essential for the function of sensory and motor systems associated with pain transmission and rhythmic motor patterns. Yet, the way glycinergic circuits modulates motor systems via the globus pallidus external (GPe) is not clear. The cyto-architecture of glycinergic circuitry is poorly understood and most work has focused in brainstem areas. It is believed that glycinergic neurons are mainly interneurons regulating local circuits. However, it is now becoming clear that they are also projection neurons, constituting true neuronal circuits. At the glycinergic synapse, termination of neurotransmission and recycling of glycine is regulated by two transporters, glycine transporter 1 …

Acute And Chronic Effects Of Inhalants In Intracranial Self-Stimulation, Matthew Tracy

Theses and Dissertations

Inhalants are a loosely defined diverse group of volatile substances which people abuse. Despite widespread misuse of inhalants, there are limited preclinical methods available to study the reinforcement-like properties of inhalants. One procedure which has demonstrated substantial promise as a tool to investigate inhalant pharmacology is the intracranial self-stimulation (ICSS) procedure. ICSS utilizes pulses of electrical stimulation to the mesolimbic reward pathway to serve as a temporally defined and controlled operant reinforcer with a highly adjustable efficacy. The first aim of the project was to characterize the effects of commonly abused inhalants: including toluene, trichloroethane, nitrous oxide, isoflurane and R134a …

Reduced Conscious Recollection And Its Detection In Three Performance Validity Tests : A Dual Task Interference Investigation, Graham Michael Silk-Eglit

Legacy Theses & Dissertations (2009 - 2024)

Performance validity is an essential component of neuropsychological assessment. Research suggests that examinees with specific neurological conditions cannot successfully complete certain performance validity tests (PVTs). However, very little basic research has explored the information processing underlying performance on PVTs that might explain why these examinees fail certain PVTs. The current study used a dual task interference paradigm to isolate the impact of reducing conscious recollection on the performance of three PVTs, the Test of Memory Malingering (TOMM), Victoria Symptom Validity Test (VSVT), and Word Memory Test (WMT). One-hundred-and-twenty-six non-clinical undergraduate research participants were administered these three PVTs as part of …

Cortex Necessary For Pain — But Not In Sense That Matters, Adam J. Shriver

Animal Sentience

Certain cortical regions are necessary for pain in humans in the sense that, at particular times, they play a direct role in pain. However, it is not true that they are necessary in the more important sense that pain is never possible in humans without them. There are additional details from human lesion studies concerning functional plasticity that undermine Key’s (2016) interpretation. Moreover, no one has yet identified any specific behaviors that mammalian cortical pain regions make possible that are absent in fish.

Fish Pain: An Inconvenient Truth, Culum Brown

Animal Sentience

Whether fish feel pain is a hot political topic. The consequences of our denial are huge given the billions of fish that are slaughtered annually for human consumption. The economic costs of changing our commercial fishery harvest practices are also likely to be great. Key outlines a structure-function analogy of pain in humans, tries to force that template on the rest of the vertebrate kingdom, and fails. His target article has so far elicited 34 commentaries from scientific experts from a broad range of disciplines; only three of these support his position. The broad consensus from the scientific community is …

Is Sentience Only A Nonessential Component Of Animal Welfare?, Ian J.H. Duncan

Animal Sentience

According to Broom (2014), animal welfare is a concept that can be applied to all animals, including single-celled organisms that are obviously not sentient. Such a stance makes it difficult to draw a connection between welfare and sentience, and that is the book’s downfall. Some excellent points are made about sentience and there are very good discussions on animal welfare. However, unless sentience is considered the essential component of welfare, any attempt to link the two phenomena will be unsuccessful — and that, indeed, is the case with this book.

Sentience And Animal Welfare: New Thoughts And Controversies, Donald M. Broom

Animal Sentience

Sentience involves having some degree of awareness but awareness of self is not as complex as some people believe. Fully functioning vertebrate animals, and some invertebrates, are sentient but neither humans nor non-humans are sentient early in development or if brain-damaged. Feelings are valuable adaptive mechanisms and an important part of welfare but are not all of welfare so the term welfare refers to all animals, not just to sentient animals. We have much to learn about what non-human animals want from us, the functioning of the more complex aspects of their brains and of our brains and how we …

Probing The Functional Relevance Of Reactive Hippocampal Neurogenesis In A Model Of An Alcohol Use Disorder, Chelsea Rhea Geil Nickell

Theses and Dissertations--Pharmacy

Alcoholism, or alcohol use disorders (AUDs), represent a major public health concern both locally and globally. Critically, excessive alcohol consumption results in neurodegeneration in brain regions such as the hippocampus which is known for its role in learning and memory. Recovery of hippocampal volume loss has been observed after prolonged abstinence, but the mechanisms underlying this process are not well understood. Adult neurogenesis is thought to contribute to this recovery since after alcohol exposure a reactive increase in adult neurogenesis is observed. This reactive neurogenesis (the process by which brain insult results in a compensatory increase in neurogenesis) may represent …

Itch Mediation And How It Differs From Pain, Nechama Rappaport

The Science Journal of the Lander College of Arts and Sciences

Itch, to most, is a common nuisance, although when chronic it can negatively affect quality of life. It is obvious that itch is processed differently than pain, but how it differs is not clear. Researchers have been trying to find a path that specifically mediates itch. They have found that itch is mediated through at least two different pathways: histamine dependent and histamine independent. However, many of the mediators involved in the transduction of itch also mediate pain. Although some itch-specific neurons have been found, the majority of the pruritogenic neurons are also responsive to pain stimuli. Two theories that …

Effects Of Vaccine Preservatives And Adjuvants On Childhood Neurodevelopment, Reut Raveh

The Science Journal of the Lander College of Arts and Sciences

Parental concerns about the safety of childhood vaccinations began in the 1990’s and continue until today. A primary concern of many parents is whether the adjuvants and preservatives added to the vaccines have the potential to cause neurodevelopmental disorders in young children. An overview of various studies was done to determine if thimerosal affects childhood neurodevelopment with studies suggesting that thimerosal potentially causes neurodevelopmental disorders. However, some studies suggest the opposite. As a result it is impossible to conclude whether thimerosal affects childhood neurodevelopment. However, measures should be taken to remove thimerosal from the childhood vaccination schedule. Additionally, the studies …

Cognitive Effects Of Breastfeeding, Abraham Englard

The Science Journal of the Lander College of Arts and Sciences

This paper explores the cognitive effects of breastfeeding through Intelligence Testing and Imaging Testing that compares IQ, success, and brain structure of individuals that were breastfed, formula fed, and both breastfed and formula fed. Intelligence studies available are widespread for all age groups and signify a causal relationship between breastfeeding and intelligence. However, imaging testing is not as extensive, but shows a strong correlation between cognitive development and breastfeeding. The mechanism of breast milk’s impact on cognitive development is at an exploratory phase, with a possibility that docosahexaenoic and arachidonic acids, along with other nutrients found in breast milk, contribute …

Natural Variation In Maternal Care And Cross-Tissue Patterns Of Oxytocin Receptor Gene Methylation In Rats, Annaliese K. Beery, Lisa M. Mcewen, Julia L. Macisaac, Darlene D. Francis, Michael S. Kobor

Neuroscience: Faculty Publications

Since the first report of maternal care effects on DNA methylation in rats, epigenetic modifications of the genome in response to life experience have become the subject of intense focus across many disciplines. Oxytocin receptor expression varies in response to early experience, and both oxytocin signaling and methylation status of the oxytocin receptor gene (Oxtr) in blood have been related to disordered social behavior. It is unknown whether Oxtr methylation varies in response to early life experience, and whether currently employed peripheral measures of Oxtr methylation reflect variation in the brain. We examined the effects of early life rearing experience …

Natural Variation In Maternal Care And Cross-Tissue Patterns Of Oxytocin Receptor Gene Methylation In Rats, Annaliese K. Beery, Lisa M. Mcewen, Julia L. Macisaac, Darlene D. Francis, Michael S. Kobor

Neuroscience: Faculty Publications

This article is part of a Special Issue "Parental Care". Since the first report of maternal care effects on DNA methylation in rats, epigenetic modifications of the genome in response to life experience have become the subject of intense focus across many disciplines. Oxytocin receptor expression varies in response to early experience, and both oxytocin signaling and methylation status of the oxytocin receptor gene (Oxtr) in blood have been related to disordered social behavior. It is unknown whether Oxtr DNA methylation varies in response to early life experience, and whether currently employed peripheral measures of Oxtr methylation reflect variation in …

Characterization Of A Medial Prefrontal Cortex - Caudal Pontine Reticular Nucleus Relevant To Sensorimotor Gating, Sebastian Andres Pace

Open Access Theses & Dissertations

Focusing attention depends on filtering irrelevant sensory stimuli to prevent brain overload. This ability of our brain to block or “gate” such information is a pre-attentive neuronal mechanism known as sensorimotor gating (SG). SG abnormalities have been linked to a variety of psychiatric disorders, including schizophrenia. Initial studies related to the SG circuitry were performed more than four decades ago (Graham, 1975). However, SG is still the subject of numerous current studies involving both humans and animal models. Despite these research efforts, knowledge gaps persist regarding the identity neurons involved, their locations in different brain regions and their precise functional …

Examination Of The Rewarding Effects Of Nicotine And The Negative Effects Of Withdrawal In A Rodent Model Of Diabetes, Joseph Allan Pipkin

Open Access Theses & Dissertations

Introduction: The present study utilized a rodent model of diabetes to examine the rewarding effects of nicotine as well as negative affective states and physical signs of withdrawal from this drug. Methods: Separate groups of rats received systemic administration of vehicle or streptozotocin (STZ), which destroys the insulin-producing beta cells in the pancreas and elevates plasma glucose levels. Place conditioning procedures were utilized to compare the rewarding effects of various doses of nicotine (conditioned place preference; CPP) and the aversive effects of nicotine withdrawal (conditioned place aversion; CPA) in vehicle- and STZ-treated rats. CPA and physical signs of withdrawal were …

Mental Health Help-Seeking Intention And Organizational Climate In A Population Of Military Service Members, Mishaw Tyron Cuyler

Open Access Theses & Dissertations

Historically, psychological effects of war such as Post Traumatic Stress Disorder (PTSD) have been understated and misdiagnosed throughout the world. Military members that displayed symptoms of PTSD such as anxiety, depression, and sadness were thought to lack the strength and courage necessary to be a soldier. As a result, many soldiers suffering from symptoms of PTSD would suffer in silence and not seek the requisite help for mental health care. This Dissertation examines the mental health help-seeking intention of U.S. military service members using the Theory of Planned Behavior (TPB). Additionally, this Dissertation considers the effects that leadership support climate …

Perceived Threat Associated With Police Officers And Black Men Predicts Support For Policing Policy Reform, Allison L. Skinner, Ingrid J. Haas

Center for Brain, Biology, and Behavior: Faculty Publications

Racial disparities in policing and recent high-profile incidents resulting in the deaths of Black men have ignited a national debate on policing policies. Given evidence that both police officers and Black men may be associated with threat, we examined the impact of perceived threat on support for reformed policing policies. Across three studies we found correlational evidence that perceiving police officers as threatening predicts increased support for reformed policing practices (e.g., limiting the use of lethal force and matching police force demographics to those of the community). In contrast, perceiving Black men as threatening predicted reduced support for policing policy …

Evaluating Competition Between Verbal And Implicit Systems With Functional Near-Infrared Spectroscopy, Troy A. Schiebel

Honors Undergraduate Theses

In category learning, explicit processes function through the prefrontal cortex (PFC) and implicit processes function through the basal ganglia. Research suggested that these two systems compete with each other. The goal of this study was to shed light on this theory. 15 undergraduate subjects took part in an event-related experiment that required them to categorize computer-generated line-stimuli, which varied in length and/or angle depending on condition. Subjects participated in an explicit "rule-based" (RB) condition and an implicit "information-integration" (II) condition while connected to a functional near-infrared spectroscopy (fNIRS) apparatus, which measured the hemodynamic response (HR) in their PFC. Each condition …

The Effect Of Caffeine On Migraine Headaches, Deborah Shimshoni

Honors Undergraduate Theses

As the most widely consumed drug around the globe, there is a vast array of contradicting research available on caffeine. One of the most debated and researched topics on caffeine is its effect on the brain. Meanwhile, the data on the neurological condition of migraine has information scattered throughout countless research articles and experiments.

Although neither migraine or caffeine are completely understood by the medical world, this analysis attempts to give a more coherent understanding of the relationship between the two. This is done by first understanding the known and theorized mechanisms of caffeine as well as the pathologies of …

The Role Of Sox4 In Regulating Choroid Fissure Closure And Retinal Neurogenesis, Wen Wen

Theses and Dissertations--Biology

The development of the vertebrate eye is tightly controlled by precise genetic regulations. From a single ocular primordium to bilateral eyes with complex structures and cell types, it requires intensive proliferation and migration for cells in both the ectoderm and mesoderm to accomplish ocular morphogenesis, and during this process cell differentiation and interaction takes place to establish the complex composition of ocular cell types and cellular connections. Genetic defects can lead to severe abnormalities in eye morphogenesis and cell differentiation during ocular development. A tremendous amount of work has been done to identify both intrinsic and extrinsic factors that regulate …

The Role Of Astrocytic Calcineurin Activation And Downstream Signaling In Neurodegenerative Diseases, Melanie M. Pleiss

Theses and Dissertations--Pharmacology and Nutritional Sciences

Calcineurin (CN) is a calcium (Ca²⁺)-sensitive serine/threonine protein phosphatase that plays a significant role in several cell signaling pathways, and has been implicated in many neurodegenerative diseases including Alzheimer’s disease (AD) and vascular cognitive impairment and dementia (VCID). Although normally found in neurons, CN also appears at high levels in activated astrocytes under conditions of injury and disease. To elucidate the role of astrocytic calcineurin signaling in neurodegenerative diseases, our lab has used primary rat astrocytes, transgenic and diet-induced mouse models of dementia, and human tissue biospecimens from confirmed AD and VCID cases.

To better understand mechanisms for …

Sensitivity Of Composite Scores To Amyloid Burden In Preclinical Alzheimer's Disease: Introducing The Z-Scores Of Attention, Verbal Fluency, And Episodic Memory For Nondemented Older Adults Composite Score, Yen Ying Lim, Peter J. Snyder, Robert H. Pietrzak, Albulene Ukiqi, Victor L. Villemagne, David Ames, Olivier Salvado, Pierrick Bourgeat, Ralph N. Martins, Colin L. Masters, Christopher C. Rowe, Paul Maruff

Research outputs 2014 to 2021

Introduction:

Cognitive composite scores developed for preclinical Alzheimer's disease (AD) often consist of multiple cognitive domains as they may provide greater sensitivity to detect β-amyloid (Aβ)-related cognitive decline than episodic memory (EM) composite scores alone. However, this has never been empirically tested. We compared the rate of cognitive decline associated with high Aβ (Aβ+) and very high Aβ (Aβ++) in cognitively normal (CN) older adults on three multidomain cognitive composite scores and one single-domain (EM) composite score.

Methods:

CN older adults (n = 423) underwent Aβ neuroimaging and completed neuropsychological assessments at baseline, and at 18-, 36-, 54-, …