Neuroscience and Neurobiology Commons^™

Reverse Genetic Screening Of Innexin Gap Junction Proteins In Drosophila Neurons, Shannon P. Fox

Senior Honors Projects, 2010-2019

The reflexive response and perception of pain (nociception) is an evolutionarily conserved process in animals. Pain can be a major health concern and current treatments often prove insufficient, especially in regards to chronic pain. Greater understanding of the molecular processes underlying pain sensation could lead to new and more effective treatments. The aim of this study is to investigate the molecular mechanisms of cold nociception in Drosophila melanogaster. A specific subset of peripheral sensory neurons (Class III dendritic arborization (da) neurons), are implicated in Drosophila larvae’s response to noxious cold.

Previous literature has associated a family of gap junction protein, …

Expression And Function Of Inflammation-Associated Micrornas In Traumatic Brain Injury, Emily Harrison

Theses & Dissertations

MicroRNAs (miRNAs) are important regulators of gene expression. Many neurological diseases, including traumatic brain injury alter expression of miRNAs in the brain. However, the function of these molecules in the context of TBI is largely unknown. Here we report multiple potential roles for miRNAs in TBI, some of which extend beyond the traditional model of post-transcriptional regulation, highlighting that these RNA molecules may have broader implications for the neurobiology of disease. We found that miR-155 plays an essential role in interferon expression after CCI and that miR-155 contributes to TBI induced anxiety, potentially through regulation of interferons. Expression of miR-155 …

The Effects Of Chronic Partial Sleep Deprivation And Chronic Voluntary Alcohol Consumption On Δfos B Accumulation, Kristian Ponder

Masters Theses, 2010-2019

The present study explores the relation between sleep restriction and alcohol use and the neural substrates that result from chronic behaviors. Accumulation of the transcription factors ΔFosB is suggested as a possible outcome of chronic behaviors, such as addiction. Sleep is discussed as possible mediating factor in the relationship between ΔFosB and chronic alcohol consumption. There were four experimental groups in this study: Control (C), Sleep Deprivation only (SD), Alcohol Exposure only (AO), and both sleep deprivation and alcohol exposure (B). Levels of ΔFosB accumulation in the Nucleus Accumbens (NAc) revealed a significant main effect of sleep deprivation, but no …

The Tnfα-Transgenic Rat: Hippocampal Synaptic Integrity, Cognition, Function, And Post-Ischemic Cell Loss, L. Creed Pettigrew, Richard J. Kryscio, Christopher M. Norris

Sanders-Brown Center on Aging Faculty Publications

The cytokine, tumor necrosis factor α (TNFα), is a key regulator of neuroinflammation linked to numerous neurodegenerative conditions and diseases. The present study used transgenic rats that overexpress a murine TNFα gene, under the control of its own promoter, to investigate the impact of chronically elevated TNFα on hippocampal synaptic function. Neuronal viability and cognitive recovery in TNFα Tg rats were also determined following an ischemic insult arising from reversible middle cerebral artery occlusion (MCAO). Basal CA3-CA1 synaptic strength, recorded in acute brain slices, was not significantly different between eight-week-old TNFα Tg rats and non-Tg rats. In contrast, slices from …

Ventromedial Prefrontal Cortex Damage Is Associated With Decreased Ventral Striatum Volume And Response To Reward, Maia Pujara, Carissa Philippi, Julian Motzkin, Mustafa Baskaya, Michael Koenigs

Psychology Faculty Works

The ventral striatum and ventromedial prefrontal cortex (vmPFC) are two central nodes of the “reward circuit” of the brain. Human neuroimaging studies have demonstrated coincident activation and functional connectivity between these brain regions, and animal studies have demonstrated that the vmPFC modulates ventral striatum activity. However, there have been no comparable data in humans to address whether the vmPFC may be critical for the reward-related response properties of the ventral striatum. In this study, we used fMRI in five neurosurgical patients with focal vmPFC lesions to test the hypothesis that the vmPFC is necessary for enhancing ventral striatum responses to …

Regardless Of Genotype, Offspring Of Vip-Deficient Female Mice Exhibit Developmental Delays And Deficits In Social Behavior., Hewlet Mcfarlane

Hewlet McFarlane

Pharmacological studies indicate that vasoactive intestinal peptide (VIP) may be necessary for normal embryonic development in the mouse. For example, VIP antagonist treatment before embryonic day 11 resulted in developmental delays, growth restriction, modified adult brain chemistry and reduced social behavior. Here, developmental milestones, growth, and social behaviors of neonates of VIP-deficient mothers (VIP +/-) mated to VIP +/- males were compared with the offspring of wild type mothers (VIP +/+) mated to VIP +/+ and +/- males, to assess the contributions of both maternal and offspring VIP genotype. Regardless of their own genotype, all offsprings of VIP-deficient mothers exhibited …

Social Approach Behaviors Are Similar On Conventional Versus Reverse Lighting Cycles, And In Replications Across Cohorts, In Btbr T+ Tf/J, C57bl/6j, And Vasopressin Receptor 1b Mutant Mice, Hewlet G. Mcfarlane, Mu Yang, Maria Luisa Scattoni, Vladimir Zhodzishsky, Thomas Chen, Heather Caldwell, W. Scott Young, Jacqueline N. Crawley

Hewlet McFarlane

Mice are a nocturnal species, whose social behaviors occur primarily during the dark phase of the circadian cycle. However, laboratory rodents are frequently tested during their light phase, for practical reasons. We investigated the question of whether light phase testing presents a methodological pitfall for investigating mouse social approach behaviors. Three lines of mice were systematically compared. One cohort of each line was raised in a conventional lighting schedule and tested during the light phase, under white light illumination; another cohort was raised in a reverse lighting schedule and tested during their dark phase, under dim red light. Male C57BL/6J …

Reduced Ultrasonic Vocalizations In Vasopressin 1b Knockout Mice., Hewlet Mcfarlane

Hewlet McFarlane

The neuropeptides oxytocin and vasopressin have been implicated in rodent social and affiliative behaviors, including social bonding, parental care, social recognition, social memory, vocalizations, territoriality, and aggression, as well as components of human social behaviors and the etiology of autism. Previous investigations of mice with various manipulations of the oxytocin and vasopressin systems reported unusual levels of ultrasonic vocalizations in social settings. We employed a vasopressin 1b receptor (Avpr1b) knockout mouse to evaluate the role of the vasopressin 1b receptor subtype in the emission of ultrasonic vocalizations in adult and infant mice. Avpr1b null mutant female mice emitted fewer ultrasonic …

Ventromedial Prefrontal Cortex Damage Is Associated With Decreased Ventral Striatum Volume And Response To Reward, Maia S. Pujara, Carissa L. Philippi, Julian C. Motzkin, Mustafa K. Baskaya, Michael Koenigs

Carissa Philippi

The Relationship Between Time Of Day, Mood, And Electroencephalography (Eeg) Asymmetry, Morgan Tantillo

Honors Projects

Previous researchers have had success in finding a correlation between exercise and an increase in positive mood. Researchers have also found a correlation between time of day and mood. The current study will explore the relationship between time of day, mood, and electroencephalography (EEG) asymmetry. The study utilized a convenient sample of ten undergraduate students at Bowling Green State University. Participants had baseline EEG recordings taken, and then participated in moderate exercise, followed by another EEG recording. Participants’ mood was assessed through a self-reported mood questionnaire before the condition as well as immediately after. Due to multiple statistical tests, the …

Acth Prevents Deficits In Fear Extinction Associated With Early Life Seizures, Andrew T. Massey, David K. Lerner, Gregory L. Holmes, Rod C. Scott, Amanda Hernan

Dartmouth Scholarship

Objective: Early life seizures (ELS) are often associated with cognitive and psychiatric comorbidities that are detrimental to quality of life. In a rat model of ELS, we explored long-term cognitive outcomes in adult rats. Using ACTH, an endogeneous HPA-axis hormone given to children with severe epilepsy, we sought to prevent cognitive deficits. Through comparisons with dexamethasone, we sought to dissociate the corticosteroid effects of ACTH from other potential mechanisms of action.

Results: Although rats with a history of ELS were able to acquire a conditioned fear learning paradigm and controls, these rats had significant deficits in their ability to extinguish …

Anatomical Markers For Elevated Cognition In Dinosaurs, Thomas Gaetano

Honors Projects

Much research has been conducted on brain evolution within Dinosauria. Dinosaurs were originally believed to be incapable of any advanced cognitive abilities beyond the level observed in modern reptiles. This is likely true for many dinosaurs, but recent discoveries suggest that the non-avian maniraptor dinosaurs shared many physical characteristics with their bird descendants, including body feathers and neural adaptations for flight. By studying cranial endocasts (the braincase of fossilized skulls) using computed tomography (CT), paleontologists are beginning to understand the neural changes that took place across the dinosaur-bird transition. Most of these studies are focused on the development of flight, …

Functional Role Of Each Component In Gamma Secretase Complex, Chen Hu

Doctoral Dissertations

Amyloid hypothesis is widely accepted as the centerpiece of Alzheimer’s disease (AD) pathogenesis. It is believed that the accumulation of amyloid beta (Ab) is the major deterministic factor of AD and the most important causative factor is the ratio of Ab42/Ab40. Gamma(g)-secretase defines the length of Ab and is composed of at least four subunits: presenilins (PS1 or PS2), nicastrin (NCT), anterior pharynx-defective 1 (Aph-1), and presenilin enhancer 2 (Pen-2). They have been reported to have different roles in g-secretase. For example, PS were believed as the catalytic components in g-secretase; NCT was recognized as a substrate receptor; Pen-2 was …

Investigation Of Neural Mechanisms Of Grip Relaxation, Binal Motawar

Theses and Dissertations

Neural mechanisms for grip relaxation are relatively unknown and understudied, as compared to mechanisms for grip initiation. Yet, termination of motor activity is as important as initiation in daily function. This knowledge gap presents incomplete understanding of neural control of hand function and its impairment with aging and neurologic disorders. The purpose of this dissertation was to identify and examine neural mechanisms of grip relaxation in healthy young adults, with aging, and in chronic stroke survivors. A series of experiments in healthy young adults showed that the relaxation from a maximum power grip was mediated by increase in the short-interval …

Exploring The Effect Of Novel Small Molecules On Oligodendrocyte Precursor Proliferation, Sagune Sakya

University Scholar Projects

Gliomas, a type of brain tumor, can be difficult to treat and have a poor survival rate. One pathway that leads to glioma formation is excessive signaling by platelet derived growth factors (PDGF) through PDGF receptor α (PDGFRα). Through this research, I found that novel compounds that downregulate PDGFRα decrease proliferation of Oli-neu cells, an oligodendrocyte precursor cell model, and identified signaling pathways through which these compounds may exert their effect. Further investigation may identify targets for development of glioma treatments.

Eye Movement Effects In Simulated Object Recognition Memory Impairment, Dmitriy Kazakov

Theses and Dissertations

Malingering is the purposeful fabrication of symptoms for secondary gain. Memory problems are the most reported symptom, and object recognition tests are often used in clinical settings to evaluate these claims. Past research has shown that eye movements can indirectly index memory, in that greater viewing is directed at studied stimuli 500-750 ms after display onset. The present study evaluated eye movements as a potential method of detecting feigned memory impairment. Forty-eight participants, half simulators, studied standardized images and took a memory test. Several levels of analysis were used to detect broad trends and brief effects. Simulators performed significantly worse …

Network Dynamics Of Visual Object Recognition, Mehmet C. Kadipasaoglu

Dissertations & Theses (Open Access)

Visual object recognition is the principal mechanism by which humans and many animals interpret their surroundings. Despite the complexity of neural computation required, object recognition is achieved with such rapidity and accuracy that it appears to us almost effortless. Extensive human and non-human primate research has identified putative category-selective regions within higher-level visual cortex, which are thought to mediate object recognition. Despite decades of study, however, the functional organization and network dynamics within these regions remain poorly understood, due to a lack of appropriate animal models as well as the spatiotemporal limitations of current non-invasive human neuroimaging techniques (e.g. fMRI, …

Cognitive Control Network Contributions To Memory-Guided Visual Attention, Maya L. Rosen, Chantal E. Stern, Samantha W. Michalka, Kathryn J. Devaney, David C. Somers

Neuroscience: Faculty Publications

Visual attentional capacity is severely limited, but humans excel in familiar visual contexts, in part because long-term memories guide efficient deployment of attention. To investigate the neural substrates that support memory-guided visual attention, we performed a set of functional MRI experiments that contrast long-term, memory-guided visuospatial attention with stimulus-guided visuospatial attention in a change detection task. Whereas the dorsal attention network was activated for both forms of attention, the cognitive control network (CCN) was preferentially activated during memory-guided attention. Three posterior nodes in the CCN, posterior precuneus, posterior callosal sulcus/mid-cingulate, and lateral intraparietal sulcus exhibited the greatest specificity for memory-guided …

Cannabis Use And Affective Processing: A Brain Structure Analysis, Kristin E. Maple

Theses and Dissertations

Cannabis is the most commonly used illicit drug amongst adolescents and young adults in the United States. Previously, cannabis and its components have been associated with differences in affective processing and neural functioning. Participants (ages 16-25) were cannabis users and non-users excluded for psychiatric disorders, major medical conditions, and excessive other drug use. A series of multiple regressions examined whether past year cannabis use and cannabis x gender predicted measures of emotional face processing (using the PennCNP affective battery) as well as volumes in bilateral prefrontal, temporal, limbic, and cerebellar regions, as well as frontolimbic white matter tracts. Subsequently, Pearson …

Experimental And Computational Studies Of Cortical Neural Network Properties Through Signal Processing, Wesley Patrick Clawson

Graduate Theses and Dissertations

Previous studies, both theoretical and experimental, of network level dynamics in the cerebral cortex show evidence for a statistical phenomenon called criticality; a phenomenon originally studied in the context of phase transitions in physical systems and that is associated with favorable information processing in the context of the brain. The focus of this thesis is to expand upon past results with new experimentation and modeling to show a relationship between criticality and the ability to detect and discriminate sensory input. A line of theoretical work predicts maximal sensory discrimination as a functional benefit of criticality, which can then be characterized …