Behavioral Neurobiology Commons^™

Analysis Of Newspaper Coverage Of Psilocybin From January 1, 1989 To December 31, 2019, Dax Oliver

Dissertations, Theses, and Capstone Projects

Psilocybin is a chemical compound that has received a lot of attention from medical researchers in recent years. However, this research is not merely a medical issue but a social and political one as well. In the 1960s, psilocybin and other psychedelic compounds were widely ingested outside of clinical settings. This alarmed some of the American public, resulting in severe legal restrictions on psilocybin use and research.

Today, many psilocybin advocates hope that it will avoid the negative public sentiment of the 1960s. To help gauge public sentiment about other psychoactive compounds, some studies have examined newspaper coverage, but there …

Neurodevelopmental Mechanisms Of Adverse Trauma Outcomes In Emerging Adulthood, Olena Kleshchova

Dissertations, Theses, and Capstone Projects

Background: Exposure to traumatic stress and adversity during the formative years of development can have adverse effects on mental health, neuroendocrine stress system function, and the brain, that persist into adulthood. One candidate mechanism that might confer vulnerability to enduring adverse outcomes of early life trauma is disruption of normal brain maturation. As the brain matures, functional interactions among brain regions change until the functional brain architecture (i.e., the functional connectome) reaches a mature state in adulthood. Given that different neural circuits have distinct developmental trajectories and sensitive periods, traumatic stress at a given point in development might have …

Experience-Dependent Changes In Nucleus Accumbens Activity Predict Cued Approach Learning: Contribution Of Nmda Receptors, Mercedes Vega Villar

Dissertations, Theses, and Capstone Projects

Animals learn associations between environmental cues and the natural rewards they predict (e.g., food, water, sex). As a result, reward-predictive cues come to trigger vigorous reward-seeking responses. Many neurons in the nucleus accumbens (NAc) become excited upon presentation of an already-learned reward-predictive cue. These NAc responses encode the motivational value of the cue and are necessary for the expression of the subsequent approach behavior. However, the precise temporal relationship between the emergence of cue-evoked excitations in the NAc and the acquisition of cued approach behavior remains unknown. In Experiment 1, NAc activity was recorded as rats learned to approach a …

Activation Of The Sonic Hedgehog Effector Smoothened Counteracts L-Dopa Induced Dyskinesia By Restoring Cholinergic Interneuron Function, Lauren Malave

Dissertations, Theses, and Capstone Projects

Many types of neurons act as multimodal signaling centers. Yet, we have only limited insight into the regulation and functional consequences of neuronal co-transmission. For example, dopamine (DA) neurons, whose degeneration causes motor deficits characteristic of Parkinson’s Diseases (PD), communicate with all their targets by DA but only a selective subset of their targets using GABA, Glutamate, and the secreted cell signaling protein Sonic Hedgehog (Shh). It is unknown whether Levo-dopamine (L-Dopa) induced dyskinesia (LIDs), a severely debilitating side effect of DA supplementation in PD, might appear because DA neuron targets are exposed to high DA- but low Shh- signaling …

Murine Genetic Variance In Sugar And Fat-Conditioned Flavor Preferences: Roles Of Dopamine, Opioid And Nmda Receptors And Nutritive Sensing, Tamar T. Kraft

Dissertations, Theses, and Capstone Projects

As obesity and diabetes have emerged as a severe public health crisis, understanding the mechanisms underlying the consumption of sugars and fats has become a topic of vigorous study. From a biological standpoint, genetic dispositions, neurochemical and hormonal influences, and predetermined orosensory and postingestive signals that modulate the hunger and satiety process may govern physiological aspects of the obesity puzzle. In addition to an innate appetite and attraction for simple carbohydrates and fats, learning plays an important role in modulating preferences for sugar- and fat-rich foods in rodents, including inbred mouse strains. Marked genetic variance has been observed among murine …

Neurogenesis Is Altered Between And Across Brain Regions After Neurodegeneration And Injury, Alice Perez

Dissertations, Theses, and Capstone Projects

Adult neurogenesis is the addition of new neurons in the adult brain. In mammals, neurogenesis is largely restricted to the hippocampus and olfactory bulb, which underlie learning, memory, and olfaction. In songbirds, new neurons are incorporated into telencephalic regions that subserve the production, perception, and maintenance of song. Studies of the regulation of neurogenesis have exclusively focused on a single brain region and within a single hemisphere. Interestingly, it has yet to be investigated whether there are correlations between numbers of new neurons across regions and hemispheres within the same animal. Here we examined these differences in a rat model …

Emotion Processing Deficits In Psychopathy: Does Cueing To Relevant Facial Features Increase Cognitive And Emotional Empathy?, Shawn E. Fagan

Dissertations, Theses, and Capstone Projects

Psychopathy is a multifaceted disorder characterized by a lack of cognitive and emotional empathy. The traditional model of psychopathy divides the disorder into two factors: Factor 1 consists of the interpersonal and affective traits of psychopathy while Factor 2 measures antisocial behaviors and lifestyle choices. The attention-to-the-eyes hypothesis argues that psychopathic individuals have impaired emotion recognition (specifically for fear) due to deficits in orienting attention to salient facial features like the eyes. Psychopathic individuals also display blunted autonomic responding to emotional stimuli, though whether this is due to attention-orienting deficits remains to be clarified. The present project investigated whether empathy-related …

The Role Of The Direct And Indirect Basal Ganglia Pathways In The Learning, Performance, And Goal-Directed Control Of Action Sequences, Eric Garr

Dissertations, Theses, and Capstone Projects

Animals engage in intricately woven action sequences that are constructed from trial-and-error learning, but the mechanisms by which the brain links together individual actions which are later recalled as fluid chains of behavior are not fully understood. The aim of this dissertation is to investigate the learning and goal-directed control of action sequences in rats. Experiment 1 addresses a question that comes out of a reinforcement learning model of action sequencing: how does the extent of training change how the performance of an action sequence is impacted by reward devaluation. The data show that action sequences remain goal-directed overall regardless …

The 5-Ht1a-R Knockout Mouse As A Model Of Later Life Anxiety Disorders: Implications For Sex Differences, Tatyana Budylin

Dissertations, Theses, and Capstone Projects

Anxiety affects nearly twice as many women as it affects men across all cultures and economic groups. Importantly, girls have a higher chance of inheriting anxiety disorders than boys, and many anxiety disorders appear at a very young age. However, little is known about sex differences in brain and behavioral development and how they relate to anxiety in adulthood. Serotonin 1A receptor (5-HT_1A-R) mediated signaling has been implicated in depression and anxiety, however most studies that focus on the involvement of the 5-HT_1A-R have been conducted in adults. Little is known about how the 5-HT_{1A …}

Interhemispheric Communication And Lateralization In The Mouse Hippocampus, Jake Jordan

Dissertations, Theses, and Capstone Projects

The hippocampus is essential for memory and spatial navigation. Many theories have been proposed to explain how the hippocampus contributes to cognition; however, none has fully explained relevant neurophysiological and behavioral data. Hemispheric lateralization of hippocampal function has been reported in humans and in rodents, and lateralization of hippocampal neural circuitry has been reported in rodents. Most theories of hippocampal function fail to consider the hippocampus as a bilateral structure with hemispheric differences. Further, proposed theories of hippocampal lateralization have their own limitations in explaining empirical data concerning left/right function. Little is known about communication between the hippocampi across hemispheres. …

Post-Synaptic Mechanisms Of Early And Late Prepulse Inhibition In The Goldfish, Daniel Bronson

Dissertations, Theses, and Capstone Projects

Sensorimotor gating, or prepulse inhibition (PPI), attenuates the startle response during sensory processing by limiting sensory input to the startle circuit. In the goldfish startle circuit, a single action potential in the Mauthner-cell (M-cell) triggers the startle response. PPI in the M-cell is mediated by multiple post-synaptic mechanisms, including the activation of a tonic, shunting inhibition as well as a voltage-sensitive conductance, both of which briefly reduce M-cell excitability. However, the specific channels and pathways that modulate PPI are not fully known. This work further characterizes the post-synaptic conductances that mediate PPI by blocking voltage-gated and inward-rectifying potassium channels, antagonizing …

Ck2 Negatively Regulates 5-Ht4 Receptor Signaling In The Prefrontal Cortex And Mediates Depression-Like Behaviors, Julia Castello Saval

Dissertations, Theses, and Capstone Projects

The serotonergic system has been the major candidate in the pathophysiology of mood related disorders such as anxiety and major depressive disorder (MDD). Unfortunately, current antidepressant drugs are ineffective in 50% of the population and require chronic administration for a period of 3-6 weeks before the onset of therapeutic response. 5-HT4 receptor (5-HT₄R) agonists have emerged as potential candidates for fast antidepressant action, since an antidepressant response can be achieved after 3 days of pharmacological administration in rodents.

This dissertation aims to investigate the role of casein kinase 2 (CK2) as a regulator of 5-HT₄R expression …

Curcumin Inhibits The Ikk:Nf-Kappa B Pathway In Neural Fear Circuits, Miguel A. Briones

Dissertations, Theses, and Capstone Projects

The study of how the brain acquires fearful memories has attracted considerable experimental attention, due in part to the promise of discovering novel therapeutic approaches for psychiatric disorders that are characterized by unusually strong and persistent traumatic memories. In recent years, extensive research has focused on studying the neural and molecular mechanisms by which fear memories are acquired, stored, and retrieved in the brain. Once acquired, fear memories may be attenuated using one of 2 procedures: 1) fear extinction, which involves repeated presentation of the fear-arousing stimulus in the absence of an aversive consequence, or 2) interference with the reconsolidation …

Dietary Curcumin Promotes Resilience To Chronic Social Defeat Stress In A Highly Susceptible Mouse Strain, Antonio V. Aubry

Dissertations, Theses, and Capstone Projects

Chronic exposure to stress is a risk factor for the development of major depression and post traumatic stress disorder in humans and induces depressive- and anxiety-like phenotypes in rodents. However, there are few pharmacological interventions available that effectively treat maladaptive responses to chronic stress in the clinical setting. One therapeutic agent that has recently shown promise in treating psychiatric disorders is curcumin, a yellow-pigmented polyphenol compound found in the turmeric plant. Curcumin has been shown to prevent the development of stressed-induced depressive-like behavior in rodents and reduce symptoms of depression in clinically diagnosed patients. In this dissertation, I investigated whether …

Neonatal Stimulation Of Pkc Epsilon Signaling Normalizes Fragile X-Associated Deficits In Pvn Oxytocin Expression And Later-Life Social And Anxiety Behavior, Alexandra E. Marsillo

Dissertations, Theses, and Capstone Projects

Fragile X Syndrome (FXS) is an inherited developmental disorder characterized by disturbances in emotional and social behavior. Our studies have revealed suppressed hippocampal PKCε expression in Fmr1 knockout (KO) mice, the leading model of FXS. To compensate for this deficiency, we stimulated PKCε in neonatal KO mice by administering a selective PKCε activator, dicyclopropyl-linoleic acid (DCP-LA), and studied its effect on ventral hippocampal neurons and a proximal target of the ventral hippocampus, the hypothalamus, which regulates social and emotional behavior. We observed that at postnatal day 18 (P18), vehicle-treated KO mice displayed increased surface localization of the 3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) …

Social Influences On Songbird Behavior: From Song Learning To Motion Coordination, Iva Ljubičić

Dissertations, Theses, and Capstone Projects

Social animals learn during development how to integrate successfully into their group. How do social interactions combine to maintain group cohesion? We first review how social environments can influence the development of vocal learners, such as songbirds and humans (Chapter 1). To bypass the complexity of natural social interactions and gain experimental control, we developed Virtual Social Environments, surrounding the bird with videos of manipulated playbacks. This way we were able to design sensory and social scenarios and test how social zebra finches adjust their behavior (Chapters 2 & 3). A serious challenge is that the color output of a …

The Role Of Glutamate Neurotransmission In The Ventral Tegmental Area In The Expression Of Conditioned Approach Learning, Priscila Hachimine-Merli

Dissertations, Theses, and Capstone Projects

Conditioned stimuli (CSs) come to function as CSs by acquiring the capacity to activate the same mesocorticolimbic dopamine (DA) neurons activated by primary rewards, producing conditioned activation of these neurons and their associated motivational states. This model stipulates that CSs activate mesocorticolimbic DA systems through the activation of glutamate receptors on DA neurons in the ventral tegmental area (VTA). We tested the hypothesis that glutamate receptor stimulation in the VTA is necessary for the expression of conditioned approach. Rats were tested in a conditioned approach protocol that consisted of 7 consecutive conditioning sessions (light presentations and food were paired), one …

Regulation Of The Amyloid Precursor Protein By Prostaglandin J2, A Mediator Of Inflammation: Relevance To Alzheimer’S Disease, Teneka L. Jean-Louis

Dissertations, Theses, and Capstone Projects

Inflammation plays a major role in Alzheimer’s disease (AD). Investigating how specific mediators of inflammation contribute to neurodegeneration in AD is crucial. Our studies focused on cyclooxygenases, which are key enzymes in inflammation and highly relevant to AD. Cyclooxygenases (COX -1, constitutive; COX-2, inducible) have emerged as important determinants of AD pathogenesis and progression. COX-2 is highly induced in AD, correlating with AD severity, and COX-1 is also involved in AD. Cyclooxygenases are the rate-limiting enzymes that convert arachidonic acid into prostaglandins (PGs), the principal mediators of CNS neuroinflammation.

The overall GOAL of these studies was to address the mechanisms …

The Nucleus Accumbens Core Dopamine D1 And Glutamate Ampa/Nmda Receptors Play A Transient Role In The Performance Of Pavlovian Approach Behavior, Veronica Dobrovitsky

Dissertations, Theses, and Capstone Projects

The role of the nucleus accumbens core (NAc core) continues to be redefined with newly acquired data on neurochemical mechanisms mediating the learning and performance of behavior. Previous empirical data showed that dopamine transmission at the D1 receptor (D1R) plays a transient role in the expression of learned Pavlovian approach behavior. Here we show that, prior to overtraining, dopamine activity at D1Rs specifically within the NAc core is critical for the performance of approach behavior elicited by the recently-acquired reward-paired cue. Blockade of D1Rs in the NAc core, but not the dorsomedial striatum or NAc shell, disrupted approach responses during …

Song Rhythm Development In Zebra Finches, Julia Hyland Bruno

Dissertations, Theses, and Capstone Projects

This dissertation investigates song-rhythm learning in songbirds. Songbirds have been studied extensively in mechanistic investigations into the sensorimotor underpinnings of the cultural transmission of learned vocalizations. While several studies identified forebrain song-system neurons that generate rhythmic song patterns, we know little about how song rhythms are learned. The first part of the dissertation describes methods for detecting and analyzing birdsong rhythm patterns, and demonstrates their utility for identifying the role of song rhythms in social interactions. Results suggest that rhythm plasticity in zebra finch song may provide a potential vehicle for communication. Controlled song-learning experiments further found that developing zebra …

Distribution And Activation Of Catecholaminergic Neurons In The Brain Of Male Plainfin Midshipman Fish: Divergence In Behavior And Reproductive Phenotype, Zachary Ghahramani

Dissertations, Theses, and Capstone Projects

The plainfin midshipman fish, Porichthys notatus, provides an excellent opportunity for delimiting the influence of neurochemical content on vertebrate vocal behavior, in part because the production and recognition of social-acoustic signals is vital to their reproductive behavior. There are two distinct reproductive male morphs that follow divergent developmental trajectories with corresponding alternative reproductive tactics: type I males are the territorial/nesting morph that vocally court females during the summer breeding season while type II males do not court females, but instead sneak spawn in competition with type I males. Catecholaminergic neurons, which synthesize and release the neurotransmitters dopamine or noradrenaline, …

Behavioral Responses To Pulses Of Light In The Longfin Inshore Squid, Doryteuthis Pealeii (Lesueur, 1821), Stavros P. Hadjisolomou

Dissertations, Theses, and Capstone Projects

The coleoid cephalopods (octopus, squid, and cuttlefish) are masters of rapid, adaptive camouflage. Unlike the slower hormonal chromatophore control of flatfish and chameleons, coleoid mollusks can change body patterns in milliseconds. Visual camouflage in coleoids is driven by a sensorimotor system consisting of visual input of their surroundings, a sophisticated central nervous system for information processing, and a neuromuscular control for body patterning. Motor neurons selectively activate millions of muscles, alternately expanding and reducing the pigmented chromatophores to generate visible brown, red, orange and yellow patterns on the skin. Below the chromatophore-layered skin are two types of reflecting cells, iridophores …

Modulation Of Spasticity By Trans-Spinal Direct Current Stimulation In Animals With Spinal Cord Injury, Wagdy Mekhael

Dissertations, Theses, and Capstone Projects

Central nervous system injuries usually produce motor impairments that are exacerbated by pathologically altered muscle tone. Abnormal muscle tone interferes with voluntary movement and is associated with loss of dexterity. Prior work in our laboratory demonstrated that 30-second trans-spinal direct current (DC) stimulation can temporarily modify muscle tone in anesthetized spastic mice after spinal cord injury (SCI). These experiments described DC-induced muscle tone responses to be polarity-dependent. That is, anodal stimulation (current passed from the lumbar spine to sciatic nerve) decreased muscle tone, and cathodal stimulation (current passed from the sciatic nerve to the lumbar spine) increased it. The present …

Dopamine D1 And D3 Receptor Polypharmacology In Cocaine Reward And Cocaine Seeking, Ewa J. Galaj

Dissertations, Theses, and Capstone Projects

Background: In the search for efficacious pharmacotherapies to treat cocaine addiction much attention has been given to agents targeting D1 or D3 receptors because of the involvement of these receptors in cocaine-related behaviors. D1 and D3 receptor partial agonists and antagonists have been shown to reduce cocaine reward, reinstatement of cocaine seeking and conditioned place preference (CPP) in rodents and non-human primates. However, translation of these encouraging results with selective D1 or D3 receptor agents has been limited due to a number of factors including toxicity, poor pharmacokinetic properties and extrapyramidal and sedative side effects.

Purpose: Given the …

Adult Neurogenesis In Avian Auditory Cortex, Caudomedial Nidopallium (Ncm): Lateralization And Effects Of Statins, Shuk C. Tsoi

Dissertations, Theses, and Capstone Projects

In the first part of this paper, we investigated the basic relationship between learning, memory and adult neurogenesis using zebra finches. We found that in the auditory cortex, the left hemisphere had more new neurons than the right hemisphere. This lateralization was correlated with song learning and memory. In the second part, we used juvenile zebra finches as a model organism to study the effects of Lipitor on learning, memory and neurogenesis. We found that Lipitor impaired song learning and memory storage. Lipitor treatments also changed the morphology of new neurons and size of old neurons, suggesting statins may affect …

Neurodevelopmental Defects Associated With Gestational Exposure To Low Levels Of Dbp In Mice, Françoise Sidime

Dissertations, Theses, and Capstone Projects

The etiology of autism is thought to involve the complex interplay among genetic and environmental factors. Patterns of inheritance suggest an epigenetic component to the development of autism. A variety of environmental risk factors are known to induce epigenetic changes in DNA, affecting many genes including those autism-associated genes (AAG). The plasticizer dibutyl phthalate (DBP; CAS 84-74-2) is a developmental and reproductive toxin that causes a broad range of birth defects resulting in neurological impairments.

To date, although the effect of DBP as an endocrine and a reproductive disruptor are established, there are only few studies that address the effects …

Status Signaling And The Characterization Of A Chirp-Like Signal In The Weakly Electric Fish Steatogenys Elegans, Caitlin E. Field

Dissertations, Theses, and Capstone Projects

Sensory systems are critical to both exploratory and communicatory processes, the study of which is critical to our understanding of how animals perceive and respond to their environments. In weakly electric fishes the electrosensory system is utilized for both of these purposes. One type of communication, status signaling, is widespread across taxa and frequently hormonally modulated. This hormonal modulation keeps the signal honest, wherein the status of the sender and the production of the status signal itself are both hormone dependent. We investigated exploratory and communicatory strategies of the electromotor system in pulse-type gymnotiforms, with a focus on status communication …

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 Effects Of Environmental Enrichment On Abstinence And Relapse Using An Animal Conflict Model, Joshua Alan Peck

Dissertations, Theses, and Capstone Projects

Heroin addiction is a significant health and societal problem for which there is no effective and well-accepted long-term behavioral or pharmacological treatment. Therefore, strategies that prolong heroin abstinence should be the primary focus of heroin treatment research. There is promising evidence that environmental enrichment may indeed support drug abstinence in animals using the reinstatement model of abstinence and relapse. The current studies used an animal conflict model that captures the aversive consequences of drug seeking (as are typical in humans, e.g., arrest, incarceration, job loss, and strained social relationships) to test the effects of environmental enrichment on heroin abstinence, prolonged …

Psychic Collapse And Traumatic Defense: How The Mind Mediates Trauma Living In The Body, Patricia Kim Yoon

Dissertations, Theses, and Capstone Projects

The aim of this exploratory study was to link psychoanalytic theories of trauma and its impact on the mind with psychobiological research of how trauma lives in the body. The study has expanded on prior research (Cramer, 2003) to evidence that defense mechanisms do in fact moderate the relationship between stress and physiological response, and that there are likely individual differences in physiological response to traumatic stress. This study goes further to identify the psychological concomitants of these individual differences within an adult population exposed to potentially traumatic events (PTEs), and their proclivity for using different defense mechanisms. Defense use …