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Age Impacts Perineuronal Net Density In The Somatosensory Genital Cortex Independently Of Gonadal Steroid Hormones, Ian D. Warren Dec 2023

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 …


Sex Differences In Mood And Anxiety-Related Outcomes In Response To Adolescent Nicotine Exposure, Tsun Hay Jason Ng Aug 2023

Sex Differences In Mood And Anxiety-Related Outcomes In Response To Adolescent Nicotine Exposure, Tsun Hay Jason Ng

Electronic Thesis and Dissertation Repository

Nicotine dependence is causally linked to increased risk of mood/anxiety disorders in later life. Females are reported to experience a higher prevalence of anxiety/depressive disorders and challenges in smoking cessation therapies, suggesting a potential sex-specific response to nicotine exposure and mood/anxiety disorder risk. However, pre-clinical evidence of sex-specific responses to adolescent nicotine exposure is unclear. Thus, to determine any sex differences in anxiety/depressive-related outcomes, adolescent male and female Sprague Dawley rats received nicotine (0.4 mg/kg; 3x daily) or saline injections for 10 consecutive days, followed by behavioural testing, in-vivo electrophysiology and Western Blot analyses. Our results revealed that adolescent nicotine …


Effects Of Development On Hpa Function Following Pubertal Stress, Brittany D. Elliott Jan 2023

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 …


A Structural Examination Of The Connection Between The Amygdala And Nucleus Accumbens In Adolescents With Clinical Anxiety, Alyssa Griffith Dec 2022

A Structural Examination Of The Connection Between The Amygdala And Nucleus Accumbens In Adolescents With Clinical Anxiety, Alyssa Griffith

Biological Sciences Undergraduate Honors Theses

The prominence of anxiety disorders in today’s general population is a major public health concern. Advancing research of the underlying pathophysiology of anxiety disorders can lead to the discovery of effective treatment interventions to treat the mental and physical symptoms of anxiety, and thus improve quality of life. This study aimed to examine two brain areas in the limbic and reward systems, the amygdala and Nucleus Accumbens (NAcc), and the structural white matter connection between them. This neural circuit assigns affective valence to environmental stimuli and motivates behavior to avoid potential harm. This study utilized diffusion Magnetic Resonance Imaging (dMRI) …


The Effects Of Executive Function Between Anxiety And Math Achievement In Adolescents, Mckenzie Hall May 2022

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 Differences In Myelin Deficits And Neuroinflammatory Responses To Adolescent Drinking In Rats, Andrea Silva-Gotay Mar 2022

Sex Differences In Myelin Deficits And Neuroinflammatory Responses To Adolescent Drinking In Rats, Andrea Silva-Gotay

Doctoral Dissertations

Alcohol binge drinking during adolescence is associated with higher risk of developing alcohol use disorders later in life. Alcohol can lead to decreased white matter volume, myelin damage, and neuroinflammation in animal models of adolescent binge alcohol exposure. These deficits in turn are associated with cognitive disfunctions that are long-lasting and could contribute to alcohol abuse and alcoholism later in life. Importantly, human males are more likely to develop alcohol use disorders than females, thus the mechanisms underlying this might be different between the sexes. Understanding how alcohol impacts the developing adolescent brain can help us identify molecular and cellular …


Chronic Adolescent Stress As A Predictive Factor For The Risk Of Developing Ptsd-Like Symptoms In Adulthood, Grace K. Young Jan 2022

Chronic Adolescent Stress As A Predictive Factor For The Risk Of Developing Ptsd-Like Symptoms In Adulthood, Grace K. Young

Theses and Dissertations

Post-traumatic stress disorder is a stress and trauma based psychological disorder that is defined by the DSM-IV as an anxiety disorder that affects approximately 7.8% of people in the United States. PTSD is when those who suffer a traumatic event have intense and distressing feelings, emotions, and memories for a prolonged period of time after the event. A prominent feature of PTSD is the impaired ability to properly extinguish a fear response after a dangerous trigger or stressor is no longer present, also known as safety learning. Stressors are threats perceived within the environment that activate a response within the …


Long-Term Effects Of Adolescent Fluoxetine Exposure On Hippocampal Gene Expression In Male C57bl/6 Mice, Anapaula Themann Dec 2021

Long-Term Effects Of Adolescent Fluoxetine Exposure On Hippocampal Gene Expression In Male C57bl/6 Mice, Anapaula Themann

Open Access Theses & Dissertations

Mood-related disorders, including depression and anxiety, are prevalent among children and adolescents. This poses a public health challenge, given their adverse impact on these young populations. Treatment with the selective serotonin reuptake inhibitor fluoxetine (FLX) is the first line of pharmacological intervention in pediatric patients suffering from affect-related illnesses. Although the use of this antidepressant has been deemed efficacious in the juvenile population, the enduring neurobiological consequences of adolescent FLX exposure are not well understood. For this reason, we explored for persistent molecular adaptations, in the adult hippocampus, as a function of adolescent FLX pretreatment. To do this, we administered …


Resting State Functional Connectivity In The Default Mode Network: Relationships Between Cannabis Use, Gender, And Cognition In Adolescents And Young Adults, Megan Ritchay Aug 2021

Resting State Functional Connectivity In The Default Mode Network: Relationships Between Cannabis Use, Gender, And Cognition In Adolescents And Young Adults, Megan Ritchay

Theses and Dissertations

Introduction: Cannabis is the most commonly used illicit substance in the United States, and nearly 1 in 4 young adults are current cannabis users. The psychoactive component of cannabis, THC, is active at cannabinoid receptors, type 1, or CB1 receptors. CB1 receptors play a critical role in neural development, and chronic cannabis use causes desensitization and downregulation of these receptors. Chronic cannabis use is associated with changes in resting state functional connectivity (RSFC) in the default mode network (DMN) in adolescents and young adults, although results are somewhat inconsistent across studies, likely due to differing methodologies. Additionally, cannabis effects appear …


The Role Of Gamma Oscillations And Cortical Inhibition In The Development Of Working Memory In Adolescence, Christopher P. Walker Dec 2019

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 …


Biobehavioral Predictors Of Cannabis Use In Adolescence, Philip Aaron Spechler Jan 2019

Biobehavioral Predictors Of Cannabis Use In Adolescence, Philip Aaron Spechler

Graduate College Dissertations and Theses

Cannabis use initiated during adolescence may precipitate lasting consequences on the brain and behavioral health of the individual. However, research on the risk factors for cannabis use during adolescence has been largely cross-sectional in design. Despite the few prospective studies, even less is known about the neurobiological predictors. This dissertation improves on the extant literature by leveraging a large longitudinal study to uncover the predictors of cannabis use in adolescent samples collected prior to exposure. All data were drawn from the IMAGEN study and contained a large sample of adolescents studied at age 14 (N=2,224), and followed up at age …


Risk Profiles For Adolescent Internalizing Problems, Kelsey Elizabeth Hudson Jan 2019

Risk Profiles For Adolescent Internalizing Problems, Kelsey Elizabeth Hudson

Graduate College Dissertations and Theses

Objective: Internalizing problems are commonly diagnosed during adolescence, and are associated with distress, impairment, and negative mental health outcomes in adulthood. Thus, there is a critical need to characterize adolescents who are at the highest risk for escalating to clinical levels of internalizing problems while extending current literature and incorporating both biological and environmental predictors. This study aimed to characterized risk profiles for fourteen-year-old adolescents who developed clinical levels of internalizing (High Internalizing [HI]) problems by age nineteen, using brain, genetic, personality, cognitive, life history, psychopathology, and demographic measures. The study also examined whether there were functional and structural brain …


Early Life Immune And Physical Stress Directly Influences Anxiety-Like Behaviour In Adolescent Rats: Examining Sex Differences, Jordan M. Ward Aug 2017

Early Life Immune And Physical Stress Directly Influences Anxiety-Like Behaviour In Adolescent Rats: Examining Sex Differences, Jordan M. Ward

Electronic Thesis and Dissertation Repository

This thesis examined the effects of neonatal acute immune activation with the endotoxin, lipopolysaccharide (LPS) on postnatal days 3 and 5 on adolescent anxiety-like behaviour in rats before and after a stress period. Previous research has shown that adults rats exposed to LPS during the neonatal stage show anxiety-like behaviour following a period of stress. This thesis investigated this effect in adolescence. The present results showed significantly higher anxiety-like behaviour in saline controls, and a potential neuroprotective effect of low dose LPS (15 µg/kg) contrary to what was reported in adult rats. As well, a phase of stressful, aversive conditioning …


Predictive Modeling Of Adolescent Cannabis Use From Multimodal Data, Philip Spechler Jan 2017

Predictive Modeling Of Adolescent Cannabis Use From Multimodal Data, Philip Spechler

Graduate College Dissertations and Theses

Predicting teenage drug use is key to understanding the etiology of substance abuse. However, classic predictive modeling procedures are prone to overfitting and fail to generalize to independent observations. To mitigate these concerns, cross-validated logistic regression with elastic-net regularization was used to predict cannabis use by age 16 from a large sample of fourteen year olds (N=1,319). High-dimensional data (p = 2,413) including parent and child psychometric data, child structural and functional MRI data, and genetic data (candidate single-nucleotide polymorphisms, "SNPs") collected at age 14 were used to predict the initiation of cannabis use (minimum six occasions) by age 16. …


Effects Of Adolescent Alcohol Binge Drinking On Prefrontal Myelin, Wanette M. Vargas-Rodriguez Nov 2016

Effects Of Adolescent Alcohol Binge Drinking On Prefrontal Myelin, Wanette M. Vargas-Rodriguez

Doctoral Dissertations

Alcohol binge drinking is highly prevalent in teenagers and is associated with various harmful health effects and social problems. During adolescence, brain regions such as the prefrontal cortex (PFC) are still undergoing active development, characterized by increases in white matter volume. While the morphological details and the cellular and molecular sequences governing adolescent white matter development are not fully known, it is known that this development process is sensitive and can be disrupted. Although consumption of alcohol in a binge drinking pattern has been linked to lower white matter integrity in humans, it is important to determine if alcohol is …


Characterization Of Corticotropin-Releasing Factor Cells In The Medial Prefrontal Cortex Of Rats, Yi-Ling Lu Mar 2016

Characterization Of Corticotropin-Releasing Factor Cells In The Medial Prefrontal Cortex Of Rats, Yi-Ling Lu

Doctoral Dissertations

Corticotropin-releasing factor (CRF) is the major peptide involved in regulating the body’s autonomic, hormonal, and behavioral responses to stress. Cells that produce and release this peptide are widely distributed throughout the brain. This dissertation focuses on a specific population of CRF cells residing in the medial prefrontal cortex (mPFC) that could potentially influence a number of higher order functions through modulation of local circuits. The prefrontal cortex is known to function sub-optimally in patients suffering from various stress-related psychiatric conditions including alcohol use disorder (AUD), and dysregulated CRF signaling may be an underlying mechanism. Surprisingly little is known about this …


An Analysis Of The Interaction Of Methylphenidate And Nicotine In Adolescent Rats: Effects On Bdnf, Elizabeth D. Freeman Aug 2015

An Analysis Of The Interaction Of Methylphenidate And Nicotine In Adolescent Rats: Effects On Bdnf, Elizabeth D. Freeman

Electronic Theses and Dissertations

This investigation was an analysis of the interaction of adolescent exposure to methylphenidate (MPH; trade name: Ritalin) on nicotine sensitization and conditioned place preference (CPP) in a rodent model and underlying mechanisms of this effect. Animals were treated IP with 1 mg/kg MPH or saline using a ―school day‖ regimen of five days on, two days off, from postnatal day (P) 28-50. During the final two weeks of MPH treatment, animals were either behaviorally sensitized to nicotine (0.5 mg/kg free base) or saline for 10 days, or conditioned to nicotine or saline using the CPP behavioral paradigm. In addition, three …


The Short And Long-Term Effects Of Chronic Ketamine During Adolescence On Object Recognition Memory In Rats, William Hardin May 2015

The Short And Long-Term Effects Of Chronic Ketamine During Adolescence On Object Recognition Memory In Rats, William Hardin

Seton Hall University Dissertations and Theses (ETDs)

Prior research has demonstrated that ketamine causes deficits in object recognition and location memory following both acute and chronic administration (Pitsikas & Boultadakis, 2009; Venãncio et al., 2011). Although it is well established that abuse of many different kinds of drugs during the critical developmental period of adolescence can lead to impairments in cognition later in adulthood (Gilpin et al., 2012; Wagner et al., 2010), no research has investigated the effects of chronic ketamine administration during adolescence and its effects on behavior in adulthood. With recent research establishing that chronic ketamine during adolescence produces late-onset alterations in electrophysiology during adulthood …


Impact Of Faah Genotype And Marijuana Use On Brain Structure And Neuropsychological Performance In Emerging Adults, Skyler Gabriel Shollenbarger May 2014

Impact Of Faah Genotype And Marijuana Use On Brain Structure And Neuropsychological Performance In Emerging Adults, Skyler Gabriel Shollenbarger

Theses and Dissertations

Introduction: Chronic MJ use may be associated with higher cognitive ability impairments (see Lisdahl et al., 2013). Regions undergoing later maturation (Gogtay 2004), may be at increased risk for MJ-induced alterations. Endogenous cannabinoid signaling (ECS) is modulated by the function the enzyme Fatty Acid Amide Hydrolase (see Ho & Hilard, 2005), thus the gene encoding for this enzyme (FAAH) impacts ECS (Sipe et al., 2002). Here, we examine the impact of MJ use and FAAH genotype on PFC complexity and underlying frontal white matter (WM) integrity in young adults. Methods: Participants included 37 MJ users and 37 non-using young adults …


Attenuated Effects Of Opiates In Adolescent Vs. Adult Male Rats: Reinforcement, Relapse, And Withdrawal, James M. Doherty Jul 2011

Attenuated Effects Of Opiates In Adolescent Vs. Adult Male Rats: Reinforcement, Relapse, And Withdrawal, James M. Doherty

Neuroscience Institute Dissertations

Adolescence in humans is a vulnerable period for illicit drug use, and teenage onset of drug use is associated with long-term addiction. Adolescent sensitivity to drug reinforcement, relapse, and withdrawal has not been explored thoroughly in animal models, especially considering opiate drugs such as morphine and heroin. The present series of studies profiles adolescent sensitivity to opiates using adolescent and adult male rats to test for age differences in opiate self-administration, reinstatement, withdrawal signs, locomotor sensitization, and even brain activation during drug-seeking. To test for acute sensitivity to the reinforcing effects of morphine or heroin, we compared patterns of self-administration …


Neuroendocrine Consequences Of Binge Alcohol Exposure During Peri-Puberty On Functioning Of The Hypothalamo-Pituitary-Adrenal (Hpa) Axis, Magdalena Malgorzata Przybycien-Szymanska Jan 2011

Neuroendocrine Consequences Of Binge Alcohol Exposure During Peri-Puberty On Functioning Of The Hypothalamo-Pituitary-Adrenal (Hpa) Axis, Magdalena Malgorzata Przybycien-Szymanska

Dissertations

Binge alcohol (EtOH) exposure in adolescence is a fundamental health concern. In 2005, over 20% of teenagers between ages 15 and 17 reported binge drinking behavior within a one month period preceding the survey (Dept. of Health and Human Services: Substance Abuse and Mental Health Services Administration). Binge drinking is defined as consuming enough alcohol within a 2.0 h period to bring blood alcohol concentration above 0.08%. In the adolescent population, this type of alcohol exposure tends to be repeated. In adults, alcohol abuse has been correlated with increased incidence of mood disorders and these disorders are characterized by dysregulation …


Characterization Of The Behavioral And Neurochemical Effects Of Nicotine Withdrawal In Adolescent And Adult Rats., Luis Alberto Natividad Jan 2009

Characterization Of The Behavioral And Neurochemical Effects Of Nicotine Withdrawal In Adolescent And Adult Rats., Luis Alberto Natividad

Open Access Theses & Dissertations

Previous studies have demonstrated that the behavioral effects of nicotine withdrawal are lower in adolescent versus adult rats. However, the neurochemical mechanisms that mediate these developmental differences are presently unclear. Much work has shown that nicotine reward is mediated via enhanced dopamine neurotransmission in the mesolimbic pathway which originates in the ventral tegmental area (VTA) and terminates in several forebrain structures including the nucleus accumbens (NAcc). More recently, studies have shown that nicotine withdrawal produces a decrease in NAcc dopamine transmission, an effect that is believed to serve as a neurochemical marker of withdrawal in adult rodents. The goal of …