Neuroscience and Neurobiology Commons^™

Attrition And Assimilation: The Neural Mechanisms Of Mandarin-English Bilingualism, Natalie P. Robison

University Honors Theses

This line of research investigates attrition of native language (L1) Mandarin proficiency with increasing proficiency in English. English uses pitch to denote intonation (e.g., “it’s there?” versus “it’s there!”), while Mandarin additionally uses pitch to indicate word meanings; e.g., /he/ means “drink” when spoken with a high, level tone, or “river” when spoken with a rising tone. The present study delineates between two alternative explanations for the prior finding (Quam & Creel, 2017a) that English proficiency correlates with attrition of Mandarin tones, but not Mandarin vowels. This pattern could be explained by 1) assimilability of the Mandarin vowel contrasts used …

Flanker Task Performance In Young And Older Adults: A Behavioral And Erp Study, Fatima Medrano

Dissertations, Theses, and Capstone Projects

Research suggests that as we get older, executive function abilities decline (Hasher & Zacks, 1988; Salthouse, 1996). One affected ability is that of inhibitory control, which aids in monitoring our responses to non-target stimuli or information. Current research on inhibition reveals inconsistencies across studies. Monitoring brain responses during the Flanker (used to measure inhibitory control) task may add valuable insight into the processes underlying group differences behaviorally, by studying the N200 and P300 event-related potentials which have been associated with inhibitory control processes. This study investigated whether there are differences between older and younger adults in inhibitory control and whether …

Cross-Linguistic Differences In Neural Encoding And Processing Of Stop Consonants: The Impact Of Language Experience On Attention Allocation, Aline Dos Santos Oliveira

Dissertations, Theses, and Capstone Projects

This study aims to examine the intricate relationship between language experience and the neural processing of stop consonant speech sounds. Previous research has shown minimal differences in amplitudes and latencies of cortical Auditory Evoked Potentials (AEPs) to speech sounds across listeners from various language backgrounds. It is only towards the later latencies (around the P2 peak at 200 ms), that there have been suggestions of cross-linguistic differences. In addition, a recent study, observed an AEP difference between monolinguals and bilinguals when processing speech, specifically an "Nd effect”. The Nd effect, which is an increased negativity of the AEP is proposed …

Towards A New Role Of Mitochondrial Hydrogen Peroxide In Synaptic Function, Cliyahnelle Z. Alexander

Student Theses and Dissertations

Aerobic metabolism is known to generate damaging ROS, particularly hydrogen peroxide. Reactive oxygen species (ROS) are highly reactive molecules containing oxygen that have the potential to cause damage to cells and tissues in the body. ROS are highly reactive atoms or molecules that rapidly interact with other molecules within a cell. Intracellular accumulation can result in oxidative damage, dysfunction, and cell death. Due to the limitations of H₂O₂ (hydrogen peroxide) detectors, other impacts of ROS exposure may have been missed. HyPer7, a genetically encoded sensor, measures hydrogen peroxide emissions precisely and sensitively, even at sublethal levels, during …

How Sensory Exploration Using Expressive Arts Provides A Cohesive Experience For Children With Multiple Diagnoses, Chanelle Goguen

Expressive Therapies Capstone Theses

This thesis looks at the potential benefits and cohesive experience of sensory exploration for children with multiple diagnoses through a trauma informed lens. The researcher was inspired by Prendiville’s (2021) idea of how interactive sensory exploration and art making can help foster and develop reciprocal communication and socio-affective relationships influenced the researcher to design a method that would be used to collect data about potential similar findings. In the method, the interaction of the sensory-specific art mediums were reflected through the expressive therapies continuum (ETC) framework. The research of this thesis acknowledges and explores how trauma and adverse childhood experiences …

Inflammaging In The Alzheimer’S Brain And Beyond: Insights From A Transgenic Mouse Model On The Sex-Specific Pathophysiology Of Alzheimer’S Disease, Alicia Jeanne Barber

Dartmouth College Ph.D Dissertations

Aging and sex are major risk factors for developing late-onset Alzheimer’s disease. Compared to men, women experience worse neuropathological burden and cognitive decline despite living longer with the disease. Similarly, male 3xTg-AD mice, developed to model Alzheimer’s disease, no longer consistently exhibit standard Alzheimer’s neuropathology yet experience higher rates of mortality - providing a unique opportunity to further elucidate this dichotomy. We hypothesized that sex differences in the biological aging process yield distinct pathological and molecular Alzheimer’s disease signatures in males and females, which could be harnessed for therapeutic and biomarker development.

We aged male and female, 3xTg-AD and B6129 …

Screen For Beneficial Genetic And Chemical Modifiers In Drosophila Models Of Als And Traumatic Brain Injury, Will Bonderer

Biological Sciences Theses and Dissertations

The underlying molecular processes of aberrant protein expression in neurodegeneration are intricate and multifaceted, with ribosome-associated quality control (RQC) emerging as a promising avenue of exploration. Ribosome-associated quality control is integral to cellular function. Its evolutionarily conserved pathway encompasses a network of mechanisms designed to ensure the fidelity of protein synthesis, folding, and degradation within the cells of all eukaryotes. The ribosome, central to protein synthesis, plays a pivotal role in this quality control network, and its malfunction can lead to the accumulation of misfolded or aberrant proteins. In the context of neurodegenerative disorders, this dysfunction can have dire consequences. …

Estrogen Replacement Therapy To Reduce Neurodegeneration And Socio-Cognitive Deficits In A Female Sprague Dawley Rat Model Of Early-Onset Alzheimer’S Disease, Miriam Kirylo

Senior Theses and Projects

No abstract provided.

The Development Of Immunohistochemistry (Icc) And Transcriptomic Protocols To Uncover Neurophysiological Markers Of Stress In Red-Eyed Tree Frogs As A Novel Biome, Shirin Dadina

Senior Theses and Projects

Adverse childhood experiences (ACEs) include various forms of physical and emotional abuse that lead to detrimental long term effects. Agalychnis callidryas (red-eyed tree frogs) have been identified as a novel biomedical model for ACEs. Red-eyed tree frogs demonstrate an escape hatch mechanism under stressors including those from predators, flooding and hypoxia where the embryo undergoes an accelerated developmental process similar to what is observed in the human population regarding precocious puberty. In order to assess this model for neurobiological outcomes of ACEs, morphological and genomic protocols must be developed and validated which is this study’s focus. Paraffin embedding and microtome …

Investigating The Antibacterial And Immunomodulatory Effects Of Resolvin D2 On Monocytes And Macrophages, Cristina Maria Padovani

Theses and Dissertations

In the late phase of sepsis, immunosuppression occurs, where the host is unable to clear the pre-existing infection and is susceptible to secondary infections. It is believed that the ideal treatments for sepsis should attenuate immunosuppression so that the host can get back to homeostasis. Specialized Pro-resolving Mediators (SPMs) are endogenously- produced fatty acids that resolve infectious inflammation without being immunosuppressive. We hypothesize that an SPM – Resolvin D2 (RvD2) – can augment exhausted macrophage function during the immunosuppressive phase of sepsis. We developed a two-hit model to establish macrophage exhaustion in vitro, and found that RvD2 increased NF-κB activity, …

Altered Sensitivity To Cocaine In Adolescent Spontaneously Hypertensive Rats, A Rodent Model Of Attention-Deficit/Hyperactivity Disorder, Ingrid Schoenborn

Senior Theses and Projects

Adolescents with attention-deficit/hyperactivity disorder (ADHD) are at greater risk for psychostimulant abuse compared to those without ADHD. This may be due to alterations in the mesolimbocortical dopamine system; indeed, psychostimulant-induced dopamine release is greater in adult spontaneously hypertensive rats (SHRs; a rodent model of ADHD) compared to controls. Here, we sought to determine the extent to which neurobehavioral responses to cocaine are altered in adolescent SHRs. To begin to address this question, adolescent male and female SHRs and Sprague Dawley (SD; a reference strain) rats were first assessed for behavioural signs of ADHD, including inattention (Y-maze test) and hyperactivity (open-field …

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 …

Isolation Of Aged Mouse Primary Microglia As A Model System For Alzheimer’S Disease Research, Michael Landis

Biology Honors Papers

Microglia and their role as the immune cells of the central nervous system are an emerging area of interest within Alzheimer’s research, particularly as they have shown in a benevolent and malevolent cellular context. Models of Alzheimer’s disease are very light in studying microglia, so in this study a model of microglia isolated from aged mice is established in order to study the phagocytic activity and protein expression of microglia in response to Amyloid Beta. The cells were isolated from aged mice and cultured before being used to confirm cellular identity, as well as to measure phagocytic activity. This study …

Investigating An Optimal Motor Learning Protocol That Leads To Better Savings And Long-Term Retention Of Visuomotor Adaptation, Reshma James

Theses and Dissertations

Visuomotor adaptation is fundamental to everyday activities, from the simple act of reaching for a cup to complex athletic maneuvers. The concept of savings is particularly interesting as it sheds light on how motor skills are acquired, retained, and relearned over time. Savings refers to the phenomenon where motor skills that have been previously learned are reacquired or relearned more rapidly after a period of inactivity or after the individual has undergone de-adaptation. While it was initially believed that savings in motor adaptation stemmed from implicit learning mechanisms, recent research indicates that it is primarily attributed to explicit recall of …

Towards Understanding The Function Of An Ets-Like Gene In Nematostella Vectensis: Generation Of A Knockout Mutant Line And A Transgenic Reporter Line, Emily Bullock

Biological Sciences Undergraduate Honors Theses

Due to their unique phylogenic position as sister to Bilateria, Cnidaria are often credited with the utility of allowing for reconstruction of ancestral biology based on characteristics shared with bilaterians and other animals. This factor makes investigation into the nervous systems of cnidarians critical in understanding early neural evolution. Wamides, a class of neuropeptides, have been shown to play a regulatory role in life cycle transitions across many different species. The cnidarian specific Wamide neuropeptide, GLWamide, has previously been identified to play an accelerator role in the metamorphic timing of a specific species of sea anemone, Nematostella vectensis. However, …

Exploring Available Information On The Gut-Brain Axis And Alzheimer’S Disease For Clinicians Making Dietary Recommendations: A Scoping Review, Megan Gibson

Electronic Theses and Dissertations

Abstract: Alzheimer’s Disease (AD) is a complex neurodegenerative disease that requires interprofessional collaboration. Pharmacological options are currently ineffective, increasing the need for preventative strategies to combat the rise of AD. Considerations of gut-targeted interventions have increased as a key component in the prevention of AD, based on the understanding that the state of the gut microbiome can impact cognitive function through the pathway known as the gut-brain axis.

Methods: This scoping review explored information on the gut-brain axis in persons with AD. A comprehensive search was conducted in November 2023. Forty reviews and 13 human studies were analyzed.

Results: There …

Perinatal Buprenorphine Effects On Offspring Growth, Opioid Withdrawal, And Brain Morphology In Rats, Parker Barnes

Electronic Theses and Dissertations

Opioid use disorder (OUD) impacts 5.6 million people in the US. Buprenorphine (BUP) is a commonly prescribed opioid medication used to treat OUD, including in pregnant women. However, opioid use during pregnancy is associated with poorer infant outcomes including reduced fetal growth, neurodevelopmental deficits, and neonatal opioid withdrawal syndrome (NOWS). Recent clinical data suggests that providing mothers with a lower dose of BUP may result in fewer negative outcomes in infants. Here, a preclinical rodent model of low-dose perinatal BUP exposure was used to study offspring health outcomes in the neonate, juvenile, and adolescent offspring. Dams were given clinically relevant …

Biophysical Model Of Retraction Motor Neurons And Their Modification By Operant Conditioning, Maria Rasheed

Dissertations & Theses (Open Access)

Operant conditioning (OC) is a form of associative learning in which an animal modifies its behavior based on the consequences that follow that behavior. Despite its ubiquity, the underlying mechanisms of OC are poorly understood. Insights into the mechanisms of OC can be obtained by studying Aplysia feeding behavior as it can be modified by OC. This behavior is mediated by a central pattern generator (CPG) network in the buccal ganglia that contains a relatively small number of neurons. This CPG generates rhythmic motor patterns (BMPs) that move food into the gut by closing a tongue-like structure (i.e., radula) during …

Pipecolic Acid And Novel Insights Into Cerebral Malaria, Akua E. Mensah

Theses

Cerebral malaria (CM), a severe manifestation of Plasmodium infection, prompts our investigation into the nuanced role of pipecolic acid in its pathophysiology. To unravel the molecular intricacies, we conducted in vitro lysine labeling techniques of mice infected with P. berghei ANKA parasites, and human P. falciparum grown in vitro, aiming to discern the impact of Plasmodium on pipecolic acid production. Previous observations indicated an elevation in pipecolic acid levels correlating with neurological decline in children with CM. In our study, confirming elevated pipecolic acid presence in the plasma and brain tissues of CM patients and the animal model of CM, …

Evaluating Environmental Enrichment As A Preventative Treatment In A Zebrafish (Danio Rerio) Model Of Alzheimer's Disease, Ainsley Craddock

Undergraduate Honors Theses

Alzheimer’s Disease (AD) is a progressive neurodegenerative disorder that leads to several cognitive deficits, including impairments in spatial memory (Alzheimer’s Association, “What is Alzheimer’s Disease?,” 2024). This is thought to occur due to atrophy in the hippocampus and cholinergic system (Ferreira-Vieira et al., 2016). Acetylcholine receptor antagonists, such as scopolamine, can mimic the effects of AD by decreasing acetylcholine activity at muscarinic receptors in the hippocampus. Scopolamine is an antiemetic that is FDA approved to treat certain kinds of nausea, but it has become a popular pharmacological model for studying the cognitive impairments associated with AD (Bajo et al., 2015). …

Molecular Mechanisms Of Opioid Use Disorder In Human Brain Models, Emily Mendez

Dissertations & Theses (Open Access)

Opioid use disorder (OUD) is a national and global public health crisis with no end in sight. While studies from animal models hint at widespread epigenetic and transcriptomic alterations of opioid drugs, the molecular consequences of long-term exposure to opioid drugs in human brain is still unclear, and human-centered translational models are necessary to discern the human cell type-specific effects of OUD.

Using postmortem brain Brodmann area 9 (BA9) from the UTHealth Brain Collection for Research on Psychiatric Disorders, I identified angiogenic gene networks perturbed in the RNA and protein of OUD subjects, as well as downregulation of many neuron-correlated …

Loss Of Tsc2 Results In Abnormal Postnatal Neurogenesis And Striatal Hamartomas, Victoria Riley

All Dissertations

Billions of years of evolution have culminated in the most complex organ in all of biology: the brain. Its capacity to sense, store, and predict information uniquely bestows humans with the capability to generate art, music, language, and math and sets humans apart from other species. It is therefore prudent and worthwhile to study the brain and its development. A critical aspect of brain development is neurogenesis, or the production of neurons. Neurogenesis is facilitated by neural stem cells (NSCs) and is influenced by the mTORC1 signaling pathway. For NSCs to differentiate and become committed to a neuronal cell fate, …

Atlas-Based Analysis Of The Neural Projections From The Lateral Hypothalamic Area To The Lower Brainstem In The Adult Male Rat, Jessica Valeria Salcido Padilla

Open Access Theses & Dissertations

Within the last decade, the number of diseases associated with dysregulation of the neural circuits responsible for energy balance, glucosensing, and feeding control has increased. One brain region containing these circuits is the lateral hypothalamic area (LHA), which plays an important role in the sleep/wake cycle, energy balance, and motivated behavior. Although the LHA has been termed a â??feeding centerâ??, other regions within the hindbrain are known for the regulation of similar functions including energy balance, glucosensing, and feeding control. While many studies have explored and reported projections from the LHA to the hindbrain, few have further investigated the interconnections …

P300 Event-Related Potential Responses To Self-Relevant Stimuli, Jordan Razzak

Electronic Theses and Dissertations

Previous literature has suggested an apparent P300 sensitivity to self-relevant stimuli. To further explore this relationship, we asked participants to submit 10 photos, each of a particular category (e.g. footwear, plants), to be used as either targets or distractors in a given condition of an oddball task. Furthermore, we attempted to see whether the effect of self-relevance on the P300 could be induced in a participant by allowing them to study a set of unique photos which would then be used as targets. Our analysis suggested that P300 amplitude elicited in response to self-relevant stimuli used as targets was statistically …

Sdf-1Α Mediates Primary Tumor Escape In Glioblastoma Through Activation Of Mesenchymal Transitions., Charles T. Froman-Glover

College of Arts & Sciences Senior Honors Theses

Glioblastoma (GBM), a highly aggressive primary brain tumor originating in glial cells, poses a significant challenge due to its rapid growth and invasive nature within healthy brain tissue.

Current treatments involve surgical resection, chemotherapy, and radiation. These treatments alone are not enough to cure this disease, and a better understanding the mechanics of the tumor micro-environment is imperative to furthering the field of cancer research. This research focuses on understanding the tumor microenvironment's impact, specifically investigating the role of stromal cell-derived factor 1 (SDF-1) mechanics on GBM aggressiveness. SDF-1 is known to facilitate disease progression by facilitating chemotaxis toward the …

Assessing The Role Of Stim1 And Stim2 In Microglial Response To Spinal Cord Injury., Sarayu Alli

College of Arts & Sciences Senior Honors Theses

Microglia, immune cells of the central nervous system, constantly survey their environment for damage. Once damage is detected, they are activated into become reactive, resulting in morphological changes, such as larger cell bodies, and functional changes, such as releasing inflammatory mediators. The switch from surveying to reactive occurs because the microglia received signals that sense danger in the environment. The release of Ca2+ from intracellular stores is involved in store-operated calcium entry (SOCE), a signaling pathway. Recent studies have shown that calcium release from the intracellular stores is a factor of microglial activation. SOCE is specific to monitoring low calcium …

Optimization Of Tyrosine Hydroxylase Antibody For Immunohistochemistry Fluorescence Detection In Zebrafish (Danio Rerio), Madison Thurber

Theses/Capstones/Creative Projects

Dopamine is an important neurotransmitter produced through the catecholamine synthesis pathway that affects brain activity. Unregulated dopamine levels can lead to various diseases such as Parkinson’s Disease or attention deficit hyperactivity disorder (ADHD). Optimization of an immunohistochemistry protocol will allow for the quantification of tyrosine hydroxylase antibody, which indirectly allows for dopamine quantification in dopaminergic regions within the brain. However, the antibody concentration to give the optimal signal-to-noise ratio in IHC varies across studies. Through this experiment, I determined the concentration of tyrosine hydroxylase (TyrH) antibody for immunohistochemistry that gave the best signal-to-background noise ratio within several known dopaminergic regions …

Role Of Proneurotrophin-P75ntr Signaling In A Mouse Model Of Depression, Kirsten Hodgson

All Graduate Theses and Dissertations, Fall 2023 to Present

Major depressive disorder, or depression, is among the leading causes of disability globally. Despite being a large public health challenge, depression remains difficult to treat as the underlying biology is still unknown and the currently available treatments are limited in effectiveness. This experiment was to test the efficacy of the drug LM11A-31, which works on the signaling pathway of proneurotrophin-p75NTR, a pathway that is not targeted by any currently used antidepressants. Male mice underwent a repeated forced swim, with all the mice receiving saline the first two days and then half the mice receiving saline and half receiving LM11A-31 before …

Towards Understanding And Improving Speech Processing, Sonia Yasmin

Electronic Thesis and Dissertation Repository

This dissertation explores mechanisms for understanding and improving speech processing. First, I used EEG to investigate the acoustic and semantic processing of continuous naturalistic speech masked by multi-talker babble. I found that different features of the same speech signal are reflected in different aspects of the neural tracking response, which are themselves differentially affected by noise. These findings point to a complex relationship between speech intelligibility and neural speech encoding.

Next, I systematically reviewed the current advancements in speech enhancement technologies. I find that speech enhancement algorithms are limited in their generalizability to speech-noise (i.e., babble). I demonstrate that, for …

The Genomics Of Champ1: Insights Into Their Cell-Type Specificity And Developmental Trajectories, Zoe Marie Van Caugherty

MUSC Theses and Dissertations

Chromosome alignment maintaining phosphoprotein 1(CHAMP1) is a gene that encodes a zinc finger protein that is involved in in the maintenance of kinetochore-microtubule attachment and regulating chromosome segregation in mitosis. (Itoh et al., 2011) CHAMP1 mutations have been shown to be major risk factors for neurodevelopmental disorders (NDDs) and autism spectrum disorder (ASD).(Asakura et al., 2021; Isidor et al., 2016; Levy et al., 2022) Although there is information on the link between CHAMP1 mutations and NDD, the role of CHAMP1 in regulating processes of human cortical development, namely, neurogenesis, proliferation, and electrophysiological properties of newly born neurons, is unknown. This …