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Individual Differences In Age And Testosterone Are Uniquely Associated With Neural Oscillatory Activity Serving Verbal Working Memory In Children And Adolescents, Abraham D. Killanin

Theses & Dissertations

During the sensitive period of adolescence, the human brain undergoes dynamic changes in structure and function resulting in vast executive function gains. Verbal working memory (VWM) is one executive function that serves as a foundation to language acquisition, reading, and learning. Many have examined the development of VWM in youth, but few have probed age-related changes in the underlying neural oscillatory dynamics, and none have examined testosterone-related changes. We recorded magnetoencephalography during a modified Sternberg VWM task in 82 youth participants aged 6 – 14 years old and collected salivary testosterone samples. Significant oscillatory responses were identified and imaged using …

Age Impacts Perineuronal Net Density In The Somatosensory Genital Cortex Independently Of Gonadal Steroid Hormones, Ian D. Warren

Masters Theses

A hallmark of pubertal development is the rise in gonadal hormone secretions and the subsequent onset of sexual behavior. The size of the somatosensory genital cortex increases in response to both this rise in gonadal steroid hormones and sexual experience. However, whether specific markers of brain plasticity are similarly impacted by gonadal hormones during puberty is not known. Perineuronal nets (PNNs) are specialized extracellular matrix structures that unsheathe neurons as they mature, and their maturation coincides with the closure of sensitive periods across several sensory systems. PNNs in somatosensory cortex, as an example, respond to experience-dependent plasticity. Although experience-depended changes …

Investigating Task-Free Functional Connectivity Patterns In Newborns Using Functional Near-Infrared Spectroscopy, Homa Vahidi

Electronic Thesis and Dissertation Repository

Robust functional connectivity in sensorimotor resting-state network (RSN) has been linked to positive neurodevelopmental outcomes in neonates. In the current study, we aimed to map the developmental trajectory of sensorimotor RSN in awake neonates using functional near-infrared spectroscopy (fNIRS). We acquired fNIRS resting-state data from 41 healthy newborns (17 females, gestational age range=36+0 to 42+1 weeks) within the first 48 hours after birth. At the group level, we observed robust positive connectivity in numerous channel-pairs across the sensorimotor network, especially in the left hemisphere. Next, we examined the relationship between functional connectivity, gestational age and postnatal age, while controlling for …

The Genomics Of Autism-Related Genes Il1rapl1 And Il1rapl2: Insights Into Their Cortical Distribution, Cell-Type Specificity, And Developmental Trajectories, Jacob Weaver

MUSC Theses and Dissertations

Neuropsychiatric disorders have a significant impact on modern society. These disorders affect a large percentage of the population: schizophrenia has a world-wide prevalence of 1% and autism spectrum disorders (ASD) affects 1 in 59 school-aged children in the US. There is substantial evidence that most neuropsychiatric disorders have a genetic component. Thus, with the advent of high throughput sequencing much effort has gone into identifying genetic variants associated with these disorders. The emerging picture from these studies is a complex one where hundreds of genes with small effects interact with a varied landscape of common variants to result in disease. …

Effects Of Development On Hpa Function Following Pubertal Stress, Brittany D. Elliott

Graduate Theses, Dissertations, and Problem Reports

For women, two of the greatest risk factors for affective disorders are adversity experienced during puberty and later becoming pregnant. We have created a translationally relevant mouse model where we address these complex risk factors. Previously, we discovered that pregnant mice (dams) that experienced chronic variable stress (CVS) during puberty display a blunted hypothalamic-pituitary-adrenal (HPA) response when exposed to an acute stressor. Interestingly, this alteration only first becomes apparent during pregnancy, which is a sensitive period for these effects due to normative neuroendocrine changes. Further investigation of the mechanisms underlying this dysfunction revealed altered gene expression in the paraventricular nucleus …

Examining The Relationships Between Socio-Cognitive Factors And Neural Synchrony During Movie Watching Across Development, Kathleen M. Lyons

Electronic Thesis and Dissertation Repository

While different cognitive abilities mature, the conscious experiences of children likely become richer and more elaborate. A challenge in investigating relationships between cognitive development and real-world experiences is having measures that assess naturalistic processing. Movie watching offers a solution, since following the plot of a film requires cognitive processes that are similar to real-world experiences. When different adults watch the same film, their brain activity begins to align (known as neural synchrony). The strength of this alignment has been shown to reflect the degree to which different individuals are having a similar experience of the movie. While this phenomenon has …

On The Roles Of Trait Anxiety And Toll Like Receptor 4 In Amphetamine Sensitization In Adolescent Male Rats, Corey A. Calhoun

Graduate Doctoral Dissertations

Mammalian adolescence can be a difficult transition from childhood to adulthood, where increases in impulsivity and novelty- and risk-seeking are combined with heightened affect and elevated sensitivity to stress. Indeed, during adolescence, first drug use patterns emerge and in the continental United States, increasing misuse of amphetamines has been observed in adolescent youth. Myriad neural mechanisms underlie this shift in adolescence, including the dynamic remodeling of the mesocorticolimbic (MCL) pathway. Repeated drug administration affects neuroimmune substrates within the MCL circuit including toll-like receptor 4 (TLR4)Advances in addiction neuroscience indicate that drugs of abuse activate neural TLR4 and implicate glial TLR4 …

The Effects Of Executive Function Between Anxiety And Math Achievement In Adolescents, Mckenzie Hall

UNLV Theses, Dissertations, Professional Papers, and Capstones

Anxiety in Children can develop into pervasive disorders in adulthood if not treated. Research shows dysfunctional Executive Function (EF) and anxiety are both shown to have a negative impact on math achievement in children and adolescents (Trezise & Reeve, 2018; Kalaycioglu, 2015; Owens, Stevenson, Hadwin & Norgate, 2012). Chung, Weyandt, and Swentosky (2014) found biological and neuropsychological support for EF as a unitary and multifaceted processor for regulating our emotional states as well as our daily procedures. Anderson’s (2002) model of Executive Control System (ECS) allows the factors of EF to be examined using a developmental approach towards EF processes. …

Sex And Age Differences In Approach Behavior Toward A Port That Delivers Nicotine Vapor, Veronika Evangelina Espinoza

Open Access Theses & Dissertations

The goal of our laboratory is to study the mechanisms that promote nicotine use, particularly in vulnerable populations such as adolescents and females. Thus, the purpose of this thesis was to characterize age and sex differences in the motivational/rewarding effects of nicotine (Aim 1) and withdrawal behavior (Aim 2). To more closely model human use patterns, the present study employed nicotine vapor methods involving passive exposure for 14 days in adolescent and adult female and male rats. Age and sex differences in approach behavior (nosepokes) were assessed in a port that delivered nicotine plumes on Day 1 and 14. Controls …

Affective Flexibility As A Developmental Building Block Of Cognitive Reappraisal: An Fmri Study, Jordan E. Pierce, Eisha Haque, Maital Neta

Center for Brain, Biology, and Behavior: Faculty and Staff Publications

Cognitive reappraisal is a form of emotion regulation that involves reinterpreting the meaning of a stimulus, often to downregulate one’s negative affect. Reappraisal typically recruits distributed regions of prefrontal and parietal cortex to generate new appraisals and downregulate the emotional response in the amygdala. In the current study, we compared reappraisal ability in an fMRI task with affective flexibility in a sample of children and adolescents (ages 6–17, N = 76). Affective flexibility was defined as variability in valence interpretations of ambiguous (surprised) facial expressions from a second behavioral task. Results demonstrated that age and affective flexibility predicted reappraisal ability, …

Multiple Approaches To Auditory Rhythm: Development Of Sustained Musical Beat And The Relation To Language, Development Of Rhythmic Categories Via Iterated Production, And A Meta-Analytic Study Of Neural Entrainment To Beat, Karli Marie Nave

UNLV Theses, Dissertations, Professional Papers, and Capstones

Rhythm is ubiquitous to human communication, coordination, and experience of music. In this dissertation, I address three empirical questions through three different methodologies, all of which contribute to the growing body of literature on human auditory rhythm processing. In Chapter 2, I present a registered report detailing the results of independent conceptual replications of Nozaradan, Peretz, Missal, & Mouraux (2011), all using the same vetted protocol. Listeners performed the same tasks as in Nozaradan et al. (2011), with the addition of behavioral measures of perception. In neuroscience, neural correlates to musical beat perception have been identified, yet little to no …

Sex Differences In Context Fear Neural Circuitry And Behavior Across Development, Lorianna Marie Colon

Legacy Theses & Dissertations (2009 - 2024)

Over the span of five decades, staggering progress has been made in elucidating the neural circuits involved in fear learning. Research focused on rodents and healthy individuals has been instrumental in elucidating how abnormalities in this circuitry may lend to increased prevalence of various fear and anxiety disorders. However, many of the key findings concerning the acquisition, storage, and retrieval of fear memories have been established in the adult male rodent, leaving a gap in knowledge as to whether females and developing animals process fear and stress inducing information in a similar fashion. Compared to men, women are twice as …

Extended Functional Connectivity Of Convergent Structural Alterations Among Anxiety Disorders: A Meta-Analysis And Functional Connectivity Analysis, Brianna S. Pankey

FIU Electronic Theses and Dissertations

Anxiety-related disorders are some of the most pervasive mental health disorders affecting adult and youth populations. Despite growing evidence of the neurobiology associated with anxiety-related disorders, a consensus on the neurobiological mechanisms of anxiety-related disorders remains to be elucidated. We first provide background literature on the reasoning behind this dissertation in Chapter 1. In Chapter 2, we conducted a neuroimaging meta-analysis on posttraumatic stress disorder to identify convergent structural and functional alterations associated with this anxiety-related disorder among adults. In Chapter 3, we conducted a neuroimaging meta-analysis to identify convergent structural alterations across diverse groupings of anxiety-related disorders …

Brain Parcellation Selection: An Overlooked Decision Point With Meaningful Effects On Individual Differences In Resting-State Functional Connectivity, Nessa V. Bryce, John C. Flournoy, João F. Guassi Moreira, Maya L. Rosen, Kelly A. Sambook, Patrick Mair, Katie A. Mclaughlin

Neuroscience: Faculty Publications

Over the past decade extensive research has examined the segregation of the human brain into large-scale functional networks. The resulting network maps, i.e. parcellations, are now commonly used for the a priori identification of functional networks. However, the use of these parcellations, particularly in developmental and clinical samples, hinges on four fundamental assumptions: (1) the various parcellations are equally able to recover the networks of interest; (2) adult-derived parcellations well represent the networks in children's brains; (3) network properties, such as within-network connectivity, are reliably measured across parcellations; and (4) parcellation selection does not impact the results with regard to …

Vestibulospinal Circuit In The Larval Zebrafish, Zhikai Liu

Arts & Sciences Electronic Theses and Dissertations

The vestibular system sense gravity and self-motion to help animals maintain body balance. Although vestibular signals inform the brain of the directions and speed of our body movements, it still remains unclear how these sensory information are processed and organized in the central nervous system. My thesis aims to illustrate neural computation underlying central vestibular tuning and the topographic organization of the vestibular circuits. First I established a novel approach to perform whole-cell recording of synaptic inputs in vivo during multi-axis movements in the central vestibular neurons. This technical advance allowed me to simultaneously measure presynaptic and postsynaptic tuning, along …

Functional Optical Imaging Of The Developing Mouse Cortex In Health And Disease, Rachel Marlene Rahn

Arts & Sciences Electronic Theses and Dissertations

Neurodevelopmental disorders (NDDs) are a heterogeneous family of disorders characterized by the presence of abnormal developmental trajectories. Functional connectivity (FC) neuroimaging provides a minimally-invasive method by which to investigate the progression of these disorders and identify potential biomarkers of disease-related dysfunction for use in therapeutics’ development. My thesis work therefore took several approaches to the question of how the functional connectome reflects developmental change as well as system-wide perturbations from environmental or genetic factors. I explored the use of optical fluorescence and intrinsic signal imaging to characterize FC and stimulation-derived responses in a NDD model of perinatal exposure to selective …

Targeting Ampa Receptor Modulation During Early Life Adversity: A Mediator For Threat Associated Memories, Roseanna M. Zanca

Dissertations, Theses, and Capstone Projects

Early life adversity (ELA) is the exposure to a single or to multiple traumatic events before the age of 18 that go beyond the child’s coping. These adverse events are often exacerbated during adolescence particularly when cognitive performance is compromised. Adolescents who experienced ELA may show symptoms of post-traumatic stress disorder (PTSD), while not vividly recalling the early life trauma. These individuals show atypical connectivity between prefrontal-amygdala and hippocampus, all of which is associated with an increased risk of experiencing a traumatic event again later in life. While clinical research has increasingly stressed the importance in addressing the long-lasting consequences …

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 …

Early Communication Abilities Of 24-Month-Old Children With Williams Syndrome As Measured By The Communication Complexity Scale., Sean B. Woods

College of Arts & Sciences Senior Honors Theses

Williams syndrome (WS) is a neurodevelopmental disorder associated with intellectual disability accompanied by a distinct cognitive profile. Despite their socially outgoing nature, children with WS exhibit delayed communication development and specific deficits across various functions of communication. The purpose of this study was to describe the range of communication complexity observed in 24-month-olds with WS and determine relations between communication complexity and other areas of cognitive development. The communication complexity of 17 24-month-old children with WS was measured using the Communication Complexity Scale (CCS), which quantifies optimal and typical communication complexity, as well as optimal communication for Joint Attention (JA) …

The Influence Of Autism Linked Gene Topoisomerase 3b (Top3b) On Neural Development In Zebrafish, Sydney Doolittle

Honors College Theses

Autism Spectrum Disorder is a class of developmental disabilities characterized by a spectrum of social, communication, and behavioral impairments in affected individuals. Studies have shown these defects stem from abnormal brain development during critical periods during early development. The underlying genetic cause of these impairments is not well understood but is believed to be a combination of a complex pairing of genetic and environmental factors. One of the genetic factors that has been recognized to influence the phenotypic symptoms of ASD is the enzyme topoisomerase 3β (top3β.) Topoisomerases are responsible for the prevention of supercoiling during DNA replication. Top3β is …

Fgf20 In Olfactory System And Cochlea Development, Lu Morgan Yang

Arts & Sciences Electronic Theses and Dissertations

The olfactory epithelium (OE) is a neurosensory organ required for the sense of smell. Turbinates, bony projections from the nasal cavity wall, increase the surface area within the nasal cavity lined by the OE. We identified a population of OE progenitor cells that expand horizontally during development to populate all lineages of the mature OE and increase OE surface area. We show that these Fgf20-positive, epithelium-spanning progenitor (FEP) cells are responsive to Wnt/β-Catenin signaling. Wnt signaling suppresses FEP cell differentiation into OE basal progenitors and their progeny, and positively regulates Fgf20 expression. We further show that FGF20 signals to the …

Reorganization Of The Human Ventricular-Subventricular Zone Neural Stem Cell Niche In Fetal-Onset Hydrocephalus, Saurabh Kumar

University Scholar Projects

Fetal-onset hydrocephalus is a relatively common birth defect occurring in 1-2 cases per thousand births and is characterized by abnormally expanded brain ventricles. Current diagnosis for this complex pathology often involves relatively simple metrics and heavy reliance on clinician experience over objective measures. Those affected often suffer chronic headaches and cognitive deficits and may present with a bulging skill. Shunting is considered the standard treatment for communicating hydrocephalus (i.e. cerebrospinal fluid flow is physically unobstructed in the ventricular system). Shunting remains a highly invasive procedure often performed during the critical period of infancy and has a high failure rate of …

Tissue-Specific Regulation Of Pnmt By Intron Retention During Neural Development, Meeti Mehta

Digital Repository: Showcase of Undergraduate Research Excellence

No abstract provided.

Characterizing The Requirements For The Matricellular Protein, Dccn, In Nervous System Function, Elizabeth L. Catudio Garrett

Graduate Student Theses, Dissertations, & Professional Papers

The brain is organized as a complex network of specialized neurons that communicate via a combination of electrical and chemical signals. Our brains function to generate movement, control organ function, or direct complex behaviors; all of which requires the ability to regulate the flow of communication between circuits and networks. Work in this thesis addresses two areas of neuron communication: first, how does the release of more than one neurotransmitter from a single neuron impact behavior, and second, are matricellular proteins (MCPs) key contributors to synaptic transmission and neuron function? The conserved CCN family of MCPs have a …

Effects Of Gestational Ozone Exposure On Privileged Placental And Brain Barrier Integrity, Alexander I. Hamm

Theses and Dissertations

Ambient outdoor ozone, a common of component of photochemical smog and urban air pollution, is linked to various neurological and vascular pathologies. Its immediate reaction with lung surfactant after inhalation results in complete reactivity of the gas, with no active ozone passing into circulation. This indicates the presence of secondary and tertiary mediators in ozone-related systemic pathologies after pulmonary insult. In vasculature, ozone exposure is associated with an acute hypertensive phenotype apparent at least 24 hours after dose, such as experienced on a hot summer afternoon in a large metropolitan area like Los Angeles or Mexico City. However, the effects …

C-Jun Nh2-Terminal Kinase Signaling Controls Cellular Mechanisms Of Guided Cortical Interneuron Migration, Skye Eleanor Smith

Graduate Theses, Dissertations, and Problem Reports

The cerebral cortex is an intricately organized brain structure responsible for high-level functions including sensory perception, movement, memory, language, and cognition. During corticogenesis, cortical excitatory neurons and inhibitory interneurons migrate from their respective progenitor zones into the developing cerebral cortex, deposit in the correct cortical layer, and establish connections with their appropriate synaptic partners. The balance between excitation and inhibition is critical for cortical circuitry development and function. Aberrant migration of inhibitory interneurons can alter the formation of cortical circuitry and lead to several neurodevelopmental disorders including epilepsy, autism spectrum disorder, and schizophrenia. Therefore, elucidating the mechanisms responsible for inhibitory …

A Novel Switch-Like Function Of Delta-Catenin In Dendrite Development, Ryan Baumert

Dissertations & Theses (Open Access)

The formation of neuronal networks in the brain is tightly regulated, and dependent on the morphology of dendrites, the branch-like signal-receiving structures extending from neurons. Disruptions in dendrite development, or dendritogenesis, can lead to the atypical neuronal connectivity associated with multiple neurodevelopmental diseases. My research addresses molecular processes that underlie dendritogenesis via analysis of a pair of novel interactions involving the protein delta-catenin.

In neurons, delta-catenin localizes to dendrites and synapses, where it functions in their development and maintenance. Structurally, delta-catenin possesses a central Armadillo domain and a C-terminal PDZ-binding motif. This motif associates with PDZ domain-containing proteins, and is …

The Role Of Gamma Oscillations And Cortical Inhibition In The Development Of Working Memory In Adolescence, Christopher P. Walker

Dissertations & Theses (Open Access)

Adolescence is a dynamic period of social, cognitive, and biological changes. In particular, working memory, the ability to actively encode and maintain information over a short period of time, develops early in childhood and gradually increases in capacity and stability during adolescence. The precise neurophysiological mechanism by which working memory capacity increases during adolescence is unclear. The objective of this investigation was to evaluate the role of cortical gamma-band (> 30 Hz) oscillations—which are associated with working memory in adults—for the development of working memory capacity in adolescents, and to identify the extent to which the temporal profile of gamma-aminobutyric …

How Does The Brain Represent Digits? Investigating The Neural Correlates Of Symbolic Number Representation Using Fmri-Adaptation, Celia Goffin

Electronic Thesis and Dissertation Repository

How does the brain represent numerical symbols (e.g., Arabic digits)? Activity in left parietal regions correlates with symbolic number processing. Research with functional resonance imaging adaptation (fMRI-A) indicates that the intraparietal sulcus (IPS) exhibits a rebound (increase in activation) effect when a repeatedly presented number is followed by a new number. Importantly, this rebound effect is modulated by numerical ratio as well as the difference between presented numbers (distance). This ratio-dependent rebound effect could reflect a link between symbolic numerical representation and an approximate number system (ANS). In this doctoral dissertation, fMRI-A is used to investigate mechanisms underlying symbolic number …