Neuroscience and Neurobiology Commons^™

Event Perception, Emily Prychitko

Arts & Sciences Graduate Student Theses and Dissertations

We seem to perceive events, like songs playing, thunderstorms, and people having conversations. Extensive empirical research suggests that we indeed perceive events. Yet the philosophy of perception has not addressed event perception much at all. I lay out goals and methods for a fruitful philosophical investigation of event perception, then pursue that investigation. Primarily on the basis of the empirical evidence, I argue that we perceive events across the senses, and that event representations are a unique type of perceptual representation. In doing so, I address concerns about event perception as such, relative to object and property perception. I argue, …

Molecular Characterization Of A Unique Population Of Human Cortical Interneurons; Implications For Primate-Specific Development, Crina Peterson

Biomedical Sciences ETDs

The human brain consists of 86 billion neurons compared to rodent brain, which consists of 75 million neurons, and the underlying mechanisms for the increased complexity of the primate cortex are not fully elucidated. However, an increase in specific cell populations, including calretinin-expressing (CALB2/CR) interneurons (INs), has been identified. In my thesis work, I demonstrate that human pluripotent stem cells (hPSCs) differentiated to neurons by default patterning give rise to this CR population in vitro, providing a method to study their development.

Chapter I reviews cortical development and hPSCs as an appropriate proxy for studying human cortical development. Chapter …

Cortical Organization In Humans And Nonhuman Primates: The Evolution Of Cognitive Areas And Circuits, Chad Joseph Donahue

McKelvey School of Engineering Graduate Student Theses & Dissertations

Similarities in organization of cerebral cortex in humans and nonhuman primates offer the promise of leveraging data from invasive animal studies to better understand the complexities of the human brain, particularly those related to higher cognitive function (e.g. attention, working memory, language). Such comparisons necessitate the identification of convincing cortical homologues (areas or regions presumed to have derived from a common ancestor), requiring an accurate interspecies mapping of cortical areas and features. To this end, I describe (i) a survey of connectivity and its measures across primate species, particularly retrograde tracing and diffusion tractography, (ii) a morphometric analysis of cognitive …

Psychological Construct Validity, Caroline Marie Stone

Arts & Sciences Graduate Student Theses and Dissertations

A primary concern for any psychological research project is determining how to measure unobservable mental entities, such as "implicit memory", or "intelligence". Psychologists say that a measure has construct validity when they believe that a measurement method measures the construct they intend it to measure, where a construct is any theoretical term that refers to a mental entity. Construct validity, then, is the process of justifying one's belief that a measure has construct validity. My dissertation seeks to answer three related questions, 1. What is construct validity?, 2. What is the best epistemic theory of justification for construct validation?, and …

Effects Of Bimodal Transcranial Direct Current Stimulation On Modulation Of Spinal Circuitry In People With Chronic Post-Stroke Hemiparesis, John Patrick Gan, Rafael Cabrera, Lana Laudermilch, Benjamin Wolkenhauer

UNLV Theses, Dissertations, Professional Papers, and Capstones

Background: Stroke can lead to gait abnormalities such as foot drop. Foot drop can result from decreased corticospinal tract input to the ankle dorsiflexors and/or from exaggerated stretch reflexes on the soleus due to reduced reciprocal inhibition from spinal reflex pathways. Transcranial direct current stimulation (tDCS) attempts to modulate corticospinal tract input and spinal reflex pathways by delivering electrical signals to parts of the brain. The degree of neuromodulation from tDCS can be measured through the Hoffman Reflex (H-reflex)—a tool used to estimate alpha motor neuron excitability which is increased in individuals post-stroke. Purpose: The primary purpose of this study …

Proceedings From The Second Annual Society For Neurosports Conference, William R. Kochen

Journal for Sports Neuroscience

Proceedings from the Second Annual Society for NeuroSports Conference

Mental Imagery In The Regulation Of Differential Fear Conditioning: A Multimodal Investigation Involving Self-Report, Psychophysiology, And Brain Imaging, Tyler Daniel Robinson

LSU Doctoral Dissertations

Mental imagery is a common component in a range of emotion regulation techniques. However, the effectiveness and neural mechanisms of regulation via mental imagery are underexplored due to a lack of studies targeting mental imagery specifically. This discrepancy results in uncertainty regarding the mechanism of regulation in existing paradigms. Biased competition for attentional resources presents a plausible model by which a mental imagery-based distracter can downregulate response to an emotional stimulus. If visualizing an imagined distracter effectively regulates emotional response, the inclusion of mental imagery components in other techniques represents a potential confound. To address this discrepancy, this dissertation investigates …

Predicting Propofol-Induced Burst Suppression Using An Individualized Model-Based Approach Over Repeated Treatments, Jason C. Huang

Utah Space Grant Consortium

Our group is investigating the antidepressant effects of high-dose propofol, but dosing propofol to induce standardized changes in EEG activity (“burst suppression”) is challenging due to limited knowledge of each subject’s pharmacokinetics (PK) and pharmacodynamics (PD). In this paper, we approximated PK-PD models for propofol-induced burst suppression (PIBS), based on multiple subjects over repeated treatments. We then applied these models to predict BSR in each subject’s repeated treatment, then evaluate their predictive performances. We hypothesized that predicting BSR from a greater number of previous treatments would improve performance, but our current results are not conclusive enough to validate the hypothesis. …

The Effects Of Mapk Signaling On The Development Of Cerebellar Granule Cells, Kerry Morgan

University Scholar Projects

The granule cells are the most abundant neuronal type in the human brain. Rapid proliferation of granule cell progenitors results in dramatic expansion and folding of the cerebellar cortex during postnatal development. Mis-regulation of this proliferation process causes medulloblastoma, the most prevalent childhood brain tumor. In the developing cerebellum, granule cells are derived from Atoh1-expressing cells, which arise from the upper rhombic lip (the interface between the roof plate and neuroepithelium). In addition to granule cells, the Atoh1 lineage also gives rise to different types of neurons including cerebellar nuclei neurons. In the current study, I have investigated the …

The Effects Of Mapk Signaling On The Development Of Cerebellar Granule Cells, Kerry Morgan

Honors Scholar Theses

The granule cells are the most abundant neuronal type in the human brain. Rapid proliferation of granule cell progenitors results in dramatic expansion and folding of the cerebellar cortex during postnatal development. Mis-regulation of this proliferation process causes medulloblastoma, the most prevalent childhood brain tumor. In the developing cerebellum, granule cells are derived from Atoh1-expressing cells, which arise from the upper rhombic lip (the interface between the roof plate and neuroepithelium). In addition to granule cells, the Atoh1 lineage also gives rise to different types of neurons including cerebellar nuclei neurons. In the current study, I have investigated the …

Aducanumab Produced A Clinically Meaningful Benefit In Association With Amyloid Lowering, Jeffrey Cummings, Paul Aisen, Cynthia Lemere, Alireza Atri, Marwan Sabbagh, Stephen Salloway

School of Medicine Faculty Research

No abstract provided.

Neurophysiological Changes After Paired Brain And Spinal Cord Stimulation Coupled With Locomotor Training In Human Spinal Cord Injury, Timothy S. Pulverenti, Morad Zaaya, Monika Grabowski, Ewelina Grabowski Grabowski, Md. Anamul Islam, Jeffrey Li, Lynda M. Murray, Maria Knikou

Publications and Research

Neurophysiological changes that involve activity-dependent neuroplasticity mechanisms via repeated stimulation and locomotor training are not commonly employed in research even though combination of interventions is a common clinical practice. In this randomized clinical trial, we established neurophysiological changes when transcranial magnetic stimulation (TMS) of the motor cortex was paired with transcutaneous thoracolumbar spinal (transspinal) stimulation in human spinal cord injury (SCI) delivered during locomotor training. We hypothesized that TMS delivered before transspinal (TMS-transspinal) stimulation promotes functional reorganization of spinal networks during stepping. In this protocol, TMS-induced corticospinal volleys arrive at the spinal cord at a sufficient time to interact with …

Rhythm Of The Night: Brain Activity And Performance On A Sustained Attention Task Is Modulated By Circadian Typology And Time Of Day, Carly R. Cooper

Honors Thesis

The human circadian system plays an important role in biological and psychological processes in both health and disease. Circadian typology refers to individual differences in circadian rhythm and is categorized into three general chronotypes: morning, evening, and neither. Research suggests that an individual’s diurnal preference may be associated with differences in cognitive abilities, personality traits, and incidence of psychiatric disorders. In the present study, we utilized a Sustained Attention to Response Task (SART) and an electroencephalogram (EEG) in a desynchrony protocol. Morning-type and evening-type participants completed a SART task on two separate occasions during which brain activity was recorded. This …

In Utero And Postnatal Oxycodone Exposure: Implications For Intergenerational Effects, Katherine E. Odegaard

Theses & Dissertations

Prescription opioid abuse during and after pregnancy is a rising public health concern. Adding a layer of complexity is the role of heredity in the overall development of these exposed offspring. The present work uses a preclinical rat model mimicking oxycodone (oxy) exposure in utero (IUO) and postnatally (PNO) to investigate comparative and intergenerational effects in the two different exposure groups.

To understand the direct effects of IUO and PNO exposure on the F1 generation, we employed a systems biology approach encompassing proton magnetic resonance spectroscopy (¹H-MRS), electrophysiology RNA-sequencing, and pain assessment to elucidate molecular and behavioral changes …

The Neurological Abnormalities Of The Brain And Spinal Cord In Individuals With Cerebral Palsy, Michael Trevarrow

Theses & Dissertations

Cerebral palsy (CP) results from an insult to the developing brain, and it is one of the most common neurodevelopmental disorders in the United States. The insult produces a cascade of activity-dependent plastic changes within the neurophysiology and structure of the brain and spinal cord that ultimately leads to sensorimotor and mobility impairments that may increase in severity throughout the lifespan. Despite this phenomenon, there are a lack of neuroimaging studies in adults with CP, generating a knowledge gap in determining how brain and spinal cord activity and structure may be altered throughout the transition into adulthood. Furthermore, the specific …

Multimodal Neuroimaging Of Hiv And Aging, Brandon Lew

Theses & Dissertations

HIV infection remains a significant contributor to disease burden, and with the success of antiretroviral therapies, the population of people with HIV is aging. A growing literature suggests a relationship between HIV-infection and a profile of age advancement, most notably in molecular studies of epigenetics. However, despite the widely-known high prevalence of HIV-related brain atrophy, functional deficits, and HIV-associated neurocognitive disorder (HAND), epigenetic age advancement has not been linked to HIV-related changes in neuroimaging metrics.

We applied three neuroimaging methods, structural MRI, resting state functional MRI, and resting state MEG, to study the brain structure and function of 121 virally-suppressed …

Neurocognitive Impairment In People Living With Human Immunodeficiency Virus (Hiv): Risk Factors And Mortality, Zaeema Naveed

Theses & Dissertations

Despite the widespread use of combination antiretroviral therapy (cART), HIV-associated neurocognitive impairment (NCI) persists in people living with HIV (PLWH) with clinical and public health implications. Studies have generated inconsistent results regarding etiological factors for NCI in PLWH and a brief user-friendly predictive tool is desirable in clinical practice to assess the probability of having NCI in PLWH. Furthermore, factors associated with clinically meaningful decline in neurocognitive status and survival disadvantage for patients with NCI are understudied in the post-cART era. The goal of this dissertation was to investigate factors associated with baseline NCI and neurocognitive decline and the association …

Muscular Performance And Neuromuscular Fatigue Are Not Sex-Dependent During Low-Load Fatiguing Bilateral Leg Extension Exercise, Taylor K. Dinyer, Evangeline P. Soucie, Pasquale J. Succi, Caleb C. Voskuil, M. Travis Byrd, Haley C. Bergstrom

Journal for Sports Neuroscience

Purpose. This study examined the sex-related differences in muscular performance and neuromuscular (electromyographic [EMG] and mechanomyographic [MMG] amplitude [AMP] and mean power frequency [MPF]) responses during fatiguing leg extension repetitions performed at the critical load (CL). Methods. Eleven men and nine women completed one-repetition maximum (1RM) testing, repetitions to failure at 50, 60, 70, and 80% 1RM to determine CL, and repetitions to failure at CL, on separate days. The EMG and MMG, AMP and MPF signals and number of repetitions completed were recorded. Results. There were no sex-dependent responses in the %1RM that corresponded to, the number of repetitions …

Neuroactivational And Behavioral Correlates Of Psychosocial Stress-Induced Cocaine Seeking In Rats, Nicole M. Hinds, Ireneusz D. Wojtas, Desta M. Pulley, Stephany J. Mcdonald, Samantha De Guzman, Nicole E. Hubbard, Colin M. Kulick-Soper, Jessica J. Debski, Bianca Patel, Daniel Manvich

Rowan-Virtua Research Day

A prominent feature of cocaine abuse is a high risk of relapse even despite prolonged periods of abstinence. Psychosocial stress is thought to be a major contributor to the onset of cocaine craving and relapse in human substance abusers, yet most preclinical models of stress-induced relapse employ physical stressors (e.g., unpredictable footshock) or pharmacological stressors (e.g., yohimbine to elicit a drug seeking response) and do not rely upon psychosocial stress per se. Importantly, social stressors are well known to activate distinct neural circuits within the brain as compared to other stressors. It is therefore possible that currently available animal models …

The Dopamine D3 Receptor Antagonist Vk4-40 Attenuates Morphine-Induced Hyperactivity But Not Cocaine-Induced Hyperactivity In Mice, Desta M. Pulley, Jessica J. Debski, Daniel Manvich

Rowan-Virtua Research Day

In light of the increasing rates of opioid abuse in the US, the search for viable medications to treat opioid abuse disorder (OUD) has become ever more urgent. Opioids exert their abuse-related effects in part by indirectly increasing dopamine (DA) neurotransmission in the mesolimbic system, a dopaminergic projection arising in the ventral tegmental area and terminating in the nucleus accumbens. The DA D3 receptor (D3R), which belongs to the D2 family of dopamine receptors (D2, D3 , D4 receptor subtypes), is highly expressed in these brain regions and has shown strong potential as a pharmacotherapeutic target for the treatment of …