Neuroscience and Neurobiology Commons^™

You Hurt My Feelings: Autonomic And Behavioral Responses To Social Exclusion And The Moderating Effect Of Psychopathic Traits, Liat Kofler

Dissertations, Theses, and Capstone Projects

Humans have a fundamental need to form and maintain social connections, and thus experiencing social exclusion is extremely distressing as it threatens this basic human need. Individuals who are socially excluded often respond aggressively, not only towards their ostracizers but also towards innocent bystanders, with ostracism being implicated in extreme acts of violence such as school shootings. However, individual differences in behavior exist within the context of social exclusion as not everyone responds aggressively after being ostracized. Identifying risk factors for retaliatory aggressive behavior following experiences of social exclusion may facilitate the development of targeted interventions aimed at mitigating such …

Changes In The Epigenetic Landscape Of Oligodendrocyte Progenitor Cells With Time, David K. Dansu

Dissertations, Theses, and Capstone Projects

Most neonatal oligodendrocyte progenitors (nOPCs) give rise to myelinating oligodendrocytes during development, while a proportion are retained as proliferative undifferentiated cells in the adult brain (aOPCs). Previous studies have reported distinct properties for those two populations but the molecular mechanisms underlying these intrinsic differences are not well understood. Using RNA-sequencing and unbiased histone proteomics analysis, we identify transcripts and histone marks that are higher in aOPCs than nOPCs. The genome-wide ChIP-sequencing analysis of chromatin from aOPCs compared to nOPCs detects greater occupancy of the H4K8ac mark at loci corresponding to the higher transcript levels of oligodendrocyte-specific transcription factors and lipid …

Brainwaves, Memory, And Reward, Rebecca Mccune

Dissertations, Theses, and Capstone Projects

The development of effective educational curricula for enhancing learning involves the crucial consideration of effort and rewards. In the realm of education, teachers commonly employ rewards as motivational tools. Traditionally, these rewards are given to students as a recognition of their successful performance. However, a thought-provoking idea emerges: What if we were to extend rewards to students not solely based on accurate answers, but also on the effort they invest, even in cases where their actual response might be incorrect? Our study explores the potential impact of this approach on the way information is absorbed and subsequently retained, specifically focusing …

Attenuated Typicality Effect In Category-Based Inferences: Implications For Autism Spectrum Disorder, Janani Rajagopalan

Dissertations, Theses, and Capstone Projects

Individuals diagnosed with Autism Spectrum Disorder (ASD) often encounter challenges in assimilating atypical exemplars into their categorical prototypes, a cognitive hurdle that can impact their interpretative and integrative capacities. Addressing this problem, the present research sought to develop a robust methodological approach to reduce the effect of this disparity. We examined the elements embedded within the category's internal structure, with the intention of experimentally attenuating the pronounced typicality effect, which is often exaggerated in ASD.

Across four experiments, the thesis investigated the cognitive and neural underpinnings that shape the access to the typicality gradient intrinsic to a category's structure. The …

Statistical And Biological Analyses Of Acoustic Signals In Estrildid Finches, Moises Rivera

Dissertations, Theses, and Capstone Projects

Acoustic communication is a process that involves auditory perception and signal processing. Discrimination and recognition further require cognitive processes and supporting mechanisms in order to successfully identify and appropriately respond to signal senders. Although acoustic communication is common across birds, classical research has largely disregarded the perceptual abilities of perinatal altricial taxa. Chapter 1 reviews the literature of perinatal acoustic stimulation in birds, highlighting the disproportionate focus on precocial birds (e.g., chickens, ducks, quails). The long-held belief that altricial birds were incapable of acoustic perception in ovo was only recently overturned, as researchers began to find behavioral and physiological evidence …

Transcranial Direct Current Stimulation Studies Investigating The Role Of The Dlpfc In Memory And Metamemory, Casey M. Imperio

Dissertations, Theses, and Capstone Projects

Metamemory, broadly defined as knowledge about one’s own memory, is thought to consist of two separate processes, monitoring, the ability to assess the contents of your own memory, and control, altering behavior in service of memory, that work together to aide in encoding and retrieval processes. Prior work has shown that metamemory monitoring accuracy can be improved in a semantic memory task via high-definition transcranial direct current stimulation (HD-tDCS), a form of non-invasive brain stimulation, over the left dorsolateral prefrontal cortex (DLPFC). Over three experiments, the current dissertation sought to replicate and extend this work by: 1) testing the effects …

Into The Unknown: Exploring The Role Of Uncertainty In Threat-Safety Discrimination, Maia Kinney-Petrucha

Dissertations, Theses, and Capstone Projects

Learning to predict the arrival of threat is crucial to survival. Key to this learning process is the ability to discriminate between which stimuli signify safety and which signify threat. The extent to which a threat is uncertain impacts this ability, but which factors of uncertainty are primarily responsible remains unresolved. Uncertainty at the level of the stimulus can be examined in threat learning paradigms by adjusting threat reinforcement rate, referring to the frequency at which a cue is reinforced with an aversive stimulus. Previous research has shown that a continuous (more certain) threat reinforcement is associated with enhanced threat …

The Effects Of Music Therapy On Elderly Adults With Dementia, Jeante J. Jackson

Dissertations, Theses, and Capstone Projects

As people age, the brain is more susceptible to changes that diminish cognitive function. In recent years neuroscience has found convergent evidence between music therapy and brain architecture, as it has shown the generation of new connections in the brain or a reorganization and possible strengthening of existing connections already in the brain. However, the literature regarding music training’s effects on executive control, selective attention, and speech processing is lacking particularly when it comes to older populations.

This study investigated Verbal Working Memory, Visuospatial Attention and Task Initiation, and Auditory Selective Attention in a 91-year-old adult (B.P.) diagnosed with dementia. …

Modulatory Effects Of Schreckstoff On The Startle Escape Response Of Goldfish (Carassius Auratus), Denis Shor

Dissertations, Theses, and Capstone Projects

Fish face a variety of stressors in nature, a prominent one being a predatory threat to which they respond with an adaptive behavioral response thus maximizing their chances of survival. A primary anti-predatory behavior is a startle response or C-start. This behavior is controlled by two large reticulospinal neurons, the Mauthner cells (M-cells) which integrate multimodal sensory inputs. Detecting a predator involves various sensory information such as visual and mechanosensory cues but also olfaction. Indeed, following an attack, an injured fish will release an alarm pheromone (Schreckstoff) and thus acutely alert close by conspecifics. However, whether the alarm pheromone in …

Validating A New In Vivo Model To Study Als, Izabela J. Cimachowska

Student Theses and Dissertations

Buildup of oxidative stress and mitochondrial dysfunction are well known characteristics of both sporadic and hereditary amyotrophic lateral sclerosis (ALS). While both forms of the disease seem to arise from common cellular dysfunction, the genetic disease is studied to a much greater extent. Engineering novel animal models of the sporadic form of the disease is crucial for development of druggable targets to treat ALS and understand the underlying mechanisms. Interestingly, accumulation of oxidative stress by exacerbated emission of reactive oxygen species (ROS) from presynaptic mitochondria is a hallmark of both hereditary and sporadic ALS. Previous work by our laboratory showed …

Quantifying Psychostimulant-Induced Sensitization Effects On Dopamine And Acetylcholine Release Across Different Timescales, Georg Lange

Dissertations, Theses, and Capstone Projects

Drug-induced behavioral sensitization describes the phenomenon that behavioral response to a drug of abuse is getting stronger if the same psychostimulant is delivered multiple times which is much more pronounced if done in the same environmental context. A proposed neural basis is the formation of an association between contextual cues and the rewarding drug which is mediated by dopamine. Dopamine operates at different timescales and to fully understand dopamine sensitization, it is necessary to investigate dopamine release at slow (tens of minutes) but also faster (sub-second) timescales. But creating a holistic view has been difficult due to a lack of …

Analysis Of Electrophysiological Markers And Correlated Components Of Neural Responses To Discourse Coherence, Kurt M. Masiello

Dissertations, Theses, and Capstone Projects

Constructing meaning from spoken language is invaluable for learning, social interaction, and communication. In clinical populations with developmental disorders of speech comprehension, the severity of disruption can persist and vary from limiting occupational opportunities to lower performance outcomes. Previous research has reported an event-related potential (ERP) neural positivity over right hemisphere lateral anterior sites in response to semantic and discourse processing. Although useful as a marker for clinical populations of autism spectrum disorder (ASD) and developmental language disorder (DLD), little is understood about the dynamics and neural sources of this biological marker. In addition to traditional methods of ERP analysis, …

Dendritic Spine Density And Morphology In The Dorsolateral Striatum Following A High Fat Diet, Tikva Nabatian

Dissertations, Theses, and Capstone Projects

Obesity rates have been dramatically rising in recent years and in 2017-2018 more than 42% of adults in the United States were obese. Obesity is associated with numerous health problems, including cardiovascular disease, stroke, insulin resistance, and type II diabetes. The prevalence of highly palatable and calorically dense foods high in fats and sugars is a significant factor in the increase in obesity rates. Many suggest that palatable food affects the brain in ways similar to drugs of abuse, reinforcing the consumption of highly palatable foods in the same way drugs reinforce drug use. While numerous weight loss programs and …

Ubiquitination Of The Protocadherin-Γa3 Variable Cytoplasmic Domain Modulates Cell-Cell Interaction, Albert Ptashnik, Nicole Lamassa, Aliya Mambetalieva, Emily Schnall, Mike Bucaro, Greg R. Phillips

Publications and Research

The family of ∼60 clustered protocadherins (Pcdhs) are cell adhesion molecules encoded by a genomic locus that regulates expression of distinct combinations of isoforms in individual neurons resulting in what is thought to be a neural surface “barcode” which mediates same-cell interactions of dendrites, as well as interactions with other cells in the environment. Pcdh mediated same-cell dendrite interactions were shown to result in avoidance while interactions between different cells through Pcdhs, such as between neurons and astrocytes, appear to be stable. The cell biological mechanism of the consequences of Pcdh based adhesion is not well understood although various signaling …

Ultrastructural Correlates Of Axons And Synapses Belonging To Different Circuits In Ferret Primary Visual Cortex, Anjelique Sawh

Dissertations and Theses

The goal of this study was to determine differences in distinctive layers of mammalian primary visual cortex through analysis of their ultrastructural characteristics. Characterizing brain circuitry using 3-dimensional reconstruction of electron microscopy images, and subsequent ultrastructural analysis of axonal populations provides us with a better understanding of the connectivity of the neural circuits. By quantifying ultrastructural differences in axonal processes such as synaptic densities, types of synapses and their post-synaptic densities (PSDs), mitochondrial volumes, synaptic vesicle aggregates, dendritic targets, and bouton volumes, we aimed to understand whether differences in anatomical specializations among different cortical layers could underlie differences in function …

Tdcs Effects On Synaptic Plasticity And Motor Skill Learning, Forouzan Vasheghani Farahani

Dissertations and Theses

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that involves the application of low-intensity constant current to the brain through electrodes placed on the scalp. Its potential to enhance brain function and treat brain-related disorders has led to its increasing popularity due to its safety, simplicity, and affordability. However, its effectiveness remains a topic of debate.

Machine Learning Approach To Predict Tdcs-Induced Electric Current In The Human Brain, Chikako Olsen

Dissertations and Theses

Background: Transcranial direct current stimulation (tDCS) is a promising non-invasive method for treating neurological and psychiatric disorders and enhancing cognitive function. However, the underlying mechanisms of tDCS are not fully understood, and there is no ground truth for determining, non-invasively, where in the brain tDCS electrical currents flow. At the same time, effective neuronal engagement from tDCS requires accurate localization of the induced currents to specific brain target regions. Machine Learning (ML) has the potential to significantly improve the accuracy and precision of tDCS current prediction. This study aims to develop a novel approach using ML to predict the location …

Editorial: Microglia In Neuroinflammation, Pinar Ayata, Ido Amit, Carla M. Cuda

Advanced Science Research Center

Microglia are a resident innate immune cell population of the central nervous system (CNS) derived from yolk sac erythro-myeloid progenitors that migrate to the developing brain prior to the formation of the blood-brain barrier. This critical cell population has gained considerable traction in the literature as it is considered a protective barrier from CNS damage and, yet, can also serve as a primary mediator of neuroinflammation. Under normal physiological conditions, microglia perform homeostatic functions, such as parenchymal surveillance, neurotrophic support, pathogen or debris removal, and maintenance of synaptic homeostasis and neuronal plasticity.

Distinct Thalamic And Frontal Neuroanatomical Substrates In Children With Familial Vs. Non-Familial Attention-Deficit/Hyperactivity Disorder (Adhd), Rahman Baboli, Meng Cao, Jeffrey M. Halperin, Xiaobo Li

Publications and Research

Attention-deficit/hyperactivity disorder (ADHD) is a highly prevalent, inheritable, and heterogeneous neurodevelopmental disorder. Children with a family history of ADHD are at elevated risk of having ADHD and persisting its symptoms into adulthood. The objective of this study was to investigate the influence of having or not having positive family risk factor in the neuroanatomy of the brain in children with ADHD. Cortical thickness-, surface area-, and volume-based measures were extracted and compared in a total of 606 participants, including 132, 165, and 309 in groups of familial ADHD (ADHD-F), non-familial ADHD (ADHD-NF), and typically developed children, respectively. Compared to controls, …

Females Exhibit Higher Glua2 Levels And Outperform Males In Active Place Avoidance Despite Increased Amyloid Plaques In Tgf344‑Alzheimer’S Rats, Osama Chaudry, Kelechi Ndukwe, Maria Figuiredo-Perira, Peter A. Serrano, Patricia Rockwell

Publications and Research

Alzheimer’s disease (AD) is a progressive neurodegenerative disease that is most prevalent in females. While estrogen provides neuroprotection in females, sex mediated differences in the development of AD pathology are not fully elucidated. Therefore, comparing events between sexes in early-stage AD pathology may reveal more effective therapeutic targets of intervention. To address sex differences, we analyzed early-stage 9-month male and female TgF344-AD (Tg-AD) rats, an AD model carrying the APPswe and Presenilin 1 (PS1ΔE9) mutations that develops progressive age-dependent AD pathology similar to humans. Tg-AD females significantly outperformed Tg-AD males in the active place avoidance (aPAT) test that assesses hippocampal-dependent …

Role Of The G Protein Beta Gamma Subunits In Serotonin Transporter Dynamics, Nora Awadallah

Dissertations, Theses, and Capstone Projects

Serotonin is a vital neurotransmitter and hormone with significant roles in almost every organ system. In the central nervous system, serotonin mediates physiological functions that in turn guide behavior and mood. Here, serotonin is released from serotonergic neurons and exerts its effects through serotonin receptors. Regulation of serotonin neurotransmission is important for the maintenance of its physiological functions; thus, extracellular serotonin must be sequestered to limit the intensity and duration of serotonin transmission. Disproportionate transmission is strongly linked with neurological and psychiatric ailments.

Extracellular serotonin levels are primarily mediated by the serotonin transporter (SERT), a critically important plasma membrane protein …

Development And Characterization Of A Novel, Genetically- Encoded Sensor To Image Sonic Hedgehog Signaling In Functional Circuits, Sonia Bernal

Dissertations, Theses, and Capstone Projects

Dynamic neurotransmitter and neuromodulator signaling in functional circuits is the neural substrate of animal behavior and cognition. The study of said circuits requires tools with sufficient spatiotemporal dynamics that can probe complex signaling patterns and decode their functional relevance by coupling the signal to behavioral output, ideally in awake, behaving animals. Much is known about the role of classical neurotransmitters such as dopamine in behavior, but a wide variety of peptides and small molecules also regulate neuronal transmission. One of these is Shh, whose presence has been observed in a variety of brain regions known to modulate movement, perception, and …

Role Of Nuclear Lamins In Oligodendrocyte Lineage Cells, Camila Yattah

Dissertations, Theses, and Capstone Projects

Differentiation of oligodendrocytes from progenitor cells is a highly regulated process characterized by a series of molecular changes, resulting in nuclear and morphological features unique to the mature oligodendrocyte state. Heterochromatin formation starting at the nuclear periphery, as well as increased nuclear rigidity are characteristically observed. The nuclear periphery is characterized by the presence of the nuclear lamina and it has been implicated in higher-order genome organization in cells. Lamins are the protein components of the nuclear lamina, and their expression is dependent upon the cell differentiation stage of the cells. While Lamin B1 (LMNB1) expression is high in progenitors …

Unexpected Arousal Suppresses Memory And Metamemory Predictions During Associative Face-Name Recognition Task, Sameer Sabharwal-Siddiqi

Dissertations, Theses, and Capstone Projects

Successful recognition often depends on probabilistic estimation of memory-signal. Arousal has been shown to offset the influence of heuristic evidence on memory prediction. We conducted three experiments that tested whether arousal also suppresses predictions relevant to memory confidence. Experiments employed associative face-name memory tasks that included retrospective (Experiments 1 and 2) or concurrent (Experiment 3) judgements of confidence. During test, subjects were presented with a masked-affective face on a subset of trials. By timing the masked-affective face to precede a recognition judgement (Experiment 1), we replicated the finding that unexpected arousal offsets the influence of heuristic evidence on expectations of …

Competitive And Facilitative Interactions Between Pavlovian Cues In Human Associative Learning: A Behavioral And Neural Analysis, Fahd Alhazmi

Dissertations, Theses, and Capstone Projects

Learning to anticipate significant events accurately is a crucial element of survival for all species. The process by which animals acquire this knowledge has been a central question of psychological research. A fundamental assumption of many learning theories is that the predictive value assigned to cues is not simply determined by their probability of reinforcement but rather by their ability to compete with other cues present during learning. The assumption of cue competition has significantly contributed to the development of behavioral and neuroscience research for decades, as it has opened the door to new empirical and theoretical advances on the …

Gamma Protocadherin Synaptic Localization And Intracellular Trafficking Is Consistent With Distinct Adhesive And Anti-Adhesive Roles In Development, Nicole Lamassa

Dissertations, Theses, and Capstone Projects

Clustered protocadherins (Pcdhs) constitute a family of cell adhesion molecules with approximately 60 Pcdh genes clustered in a 1 MB locus on chromosome 5q31 in humans. The Pcdh gene cluster is subdivided into α, β, and γ subclusters which encode related proteins. Individual neurons activate different subsets of Pcdh-α, Pcdh-β and Pcdh-γ genes by epigenetic mechanisms to generate distinct Pcdh adhesive units expressed by each neuron. This is thought to serve as a “surface barcode” for single-cell identity and synaptic recognition in the nervous system. The actual role for Pcdhs in neural development is still relatively unknown and different roles …

Clustered Protocadherins Ubiquitination And Phosphorylation Regulates Surface Expression, Albert Ptashnik

Dissertations, Theses, and Capstone Projects

Clustered protocadherins (Pcdhs) are a family of 60 adhesion-like molecules forming a neural barcode. In vertebrate neurons, 60 Pcdhs are coded by a large gene cluster. Numerous axons in the cluster are coding for the different extracellular, transmembrane, variable portion of the cytoplasmic and constant cytoplasmic domains where their expression is controlled epigenetically. These proteins mediate interactions between axons, dendrites, and glial cells during neural development. Yet, Pcdhs are not strictly adhesion molecules. In the amacrine cells of the retina, Pcdhs promote avoidance of the same cell dendrites, where in the cortex Pcdhs promote interactions between dendrites and astrocytes. In …

The Behavioral And Gene Expression Effects Of Loss Or Exhaustion Of Sonic Hedgehog From Dopamine Neurons, Dustin R. Zuelke

Dissertations, Theses, and Capstone Projects

Mesencephalic dopamine neurons (DAN) signal motivation and reward prediction errors. Their collective functions are considered critical for the translation of thought into context appropriate actions. Dopaminergic dysfunction has severe consequences: (1) DAN degeneration is a major determinate of Parkinson’s Disease (PD), (2) disturbed dopaminergic signaling in schizophrenia leads to unorganized learning, and (3) chemically induced dopaminergic signaling results in impulse control disorders (ICDs) and life-threatening addictions. The use of the dopamine (DA) precursor L-Dopa for DA replacement therapy in PD patients produces motor and behavioral side-effects such as L-Dopa induced dyskinesias (LID), ICDs, and a propensity for opioid addiction. Despite …

Antisocial Behavior And Callous Unemotional Traits In Youth: A Biosocial Approach, Yong Lin Huang

Dissertations, Theses, and Capstone Projects

Early life presence of antisocial behavior (e.g., aggression/delinquency) and psychopathic/callous-unemotional (CU) traits (lacking empathy/remorse, shallow affect) are precursors to juvenile crime and criminal offending in adulthood. Etiological research on antisocial/CU tendencies has implicated both neurobiological (e.g., alterations in brain function and structure) and environmental (social adversity, prenatal stress) underpinnings. It has been proposed that reward and punishment processing deficits may induce problematic traits and behavior, such that antisocial/CU tendencies may be linked to hypersensitivity to rewards and hyposensitivity to punishment. Studies in this area have generated inconsistent findings and focused primarily on adult and clinical samples, leaving youth and community …

Natural Striatal Signaling Dynamics During Food Approach, Devry Mourra

Dissertations, Theses, and Capstone Projects

Reduced dopamine (DA) signaling has been hypothesized to induce compulsive overeating in obesity. However, DA signaling facilitates food pursuit by acting on direct and indirect pathways. This disparity between why individuals compulsively overeat despite decreased DA and satiety signals is unclear. Characterizing how DA and direct/indirect pathways respond to satiation may elucidate how satiety signals become overwritten in obesity. The food's palatability may underlie this, which is putatively thought to override the satiety hormones since it directly increases DA signaling, resulting in the increased appetitive drive. We determined the pattern of dopamine and pathway-specific medium spiny neuron (MSN) activity across …