Neuroscience and Neurobiology Commons^™

Effects Of Repeated Intermittent Episodes Of Social Stress On The Acquisition And Extinction Of A Reward-Seeking Task, Nikki Sullivan

Honors Theses

Repeated exposure to stress is known to have a myriad of effects on the brain, contributing to the development of psychiatric disorders, such as anxiety, depression, and drug addiction. For example, rats undergoing repeated social stress develop increased cocaine self-administration. These effects of stress are not well-understood and are related to changes in the brain reward system. This study investigated the effects of repeated social stress on reward-seeking behavior via the acquisition and extinction of a discriminative stimulus (DS) task and on anxiety-like behavior in the elevated plus maze (EPM). Male rats underwent intermittent social defeat (4 sessions in 10 …

The Raphe-Hippocampal Tract And Its Age Differences: Diffusion Tensor Imaging And Probabilistic Tractography Study, Ashley Sekul

Honors Theses

The raphe-hippocampal tract links the raphe nuclei to the hippocampus and is responsible for the production of the neurotransmitter serotonin. The hippocampus is key in regulating emotional and stress responses. This study utilized diffusion tensor imaging which uses Functional Magnetic Resonance Imaging to provide scans of the brain for analyzing differences in the raphe-hippocampal tract as one ages. In this specific study, 491 samples were visually analyzed to gather data about the fractional anisotropy of the raphe nuclei in both male and female brains ranging from 6 to 85 years old. Through the ranking of images, some were discarded, and …

Dynamic Oscillatory Interactions Between Neural Attention And Sensorimotor Systems, Alex Wiesman

Theses & Dissertations

The adaptive and flexible ability of the human brain to preference the processing of salient environmental features in the visual space is essential to normative cognitive function, and various neurologically afflicted patient groups report negative impacts on visual attention. While the brain-bases of human attentional processing have begun to be unraveled, very little is known regarding the interactions between attention systems and systems supporting sensory and motor processing. This is essential, as these interactions are dynamic; evolving rapidly in time and across a wide range of functionally defined rhythmic frequencies. Using magnetoencephalography (MEG) and a range of novel cognitive paradigms …

Effect Of Ambient Temperature On Recovery Of Surgically Instrumented Sprague-Dawley Rats, Gianna Mangone

Senior Honors Projects, 2020-current

Based on current guidelines for housing rodents after surgical instrumentation, rodents may be housed at temperatures that hinder surgical recovery and cause thermal stress– room temperature (21°C) being one of them. Rodents are often housed at room temperature since this temperature is easy for humans to be caring for them. However, if recovering rodents are thermally stressed, experimental results will be confounded. To address this issue, Sprague-Dawley rats were surgically instrumented with radiotelemtry thermoprobes (Data Sciences, #TA-10F40) to monitor their core temperatures, then housed at one of five temperatures to assess the effect ambient temperature had on multiple aspects of …

Dependence Of The Nociceptive Withdrawal Response On Stimulus Location In The Intact, Unanesthetized Rat, Brady Simpson

Senior Honors Projects, 2020-current

The nociceptive withdrawal response (NWR) is a critical movement characterized by the avoidance of noxious or otherwise unwanted stimuli. The response is mediated in mammals by withdrawal of the hind limb. Although the NWR has been studied in humans and spinalized animals, it is unclear whether there is a dependence on stimulus location in intact, unanesthetized, non-human animals. The specific aim of my research was to use high speed video of the intact, unanesthetized rat’s limb to determine if there was an effect of stimulus location on hind limb movement during the NWR evoked by heat stimuli. I hypothesized, based …

Do Innexins Function In The Extreme Cold Response Of Drosophila Melanogaster, Madison A. Ward

Masters Theses, 2020-current

Nociception is an organism’s ability to detect, process and reflexively respond to potentially damaging stimuli. While the process of nociception has clear, protective advantages, inappropriate and prolonged signaling can lead to chronic pain in humans. Nociception is a vital and genetically conserved process, thus cold nociception in Drosophilaprovides a model for identifying molecular components required for nociceptor function in vertebrates. Drosophila Class III dendritic arborization (da) neurons have previously been shown to be involved in the cold nociceptive response. Due to the importance of fast response to damaging stimuli, we hypothesize that electrical synapses are involved in cold nociception. …

The Current Neuroscientific Understanding Of Alzheimer's Disease, Rachel A. Brandes

Pursuit - The Journal of Undergraduate Research at The University of Tennessee

Alzheimer’s disease is a degenerative neurological illness characterized by the deterioration of brain regions implicated in memory and cognitive function. While researchers have yet to find a cure or effective treatment, they have gained a better understanding of its pathology and development. Through years of neuroscience research, scientists have discovered much of what happens in the brain during Alzheimer’s disease onset and how this causes its symptoms; many hypotheses regarding this aspect of the illness involve temporal lobe atrophy, neurofibrillary tangles, and amyloid plaques. Although Alzheimer’s disease affects millions of people every day, it seems that most are unaware of …

Working Memory And Attention Deficits During A Letter Number Sequencing Task Post-Concussion, Shannon Kiss

Neuroscience Honors Papers

As the prevalence of sports related concussions rise, the long-term effects of concussions have garnered increasing research attention. Previous research has demonstrated that certain dimensions of executive function are especially susceptible to mild traumatic brain injury (mTBI), specifically working memory and attention. Previous studies using EEG have found that increased very low frequency oscillations (VLFO) disrupt goal-oriented activities and are associated with difficulties in cognition, hyperactivity and inattention in concussed individuals after mTBI. This study utilized continuous EEG during a letter number sequencing task on concussed and non-concussed individuals to assess deficits related to working memory and attention. It was …

Neurocognitive Risk Factors And Current Intervention Strategies For Survivors Of Pediatric Acute Lymphoblastic Leukemia, Abigail Taber

Senior Honors Theses

The improved survival rate for pediatric cancer patients is one of the greatest triumphs of recent medicine, but the late effects faced by these survivors have been uncovered through this new population of survivors. Many survivors of pediatric acute lymphoblastic leukemia (ALL) experience cognitive deficits in areas such as attention, memory, processing speed, and academic achievement following cancer treatment. Recent research has pointed to chemotherapeutic agents, host risk factors, and genetic predispositions as perpetrators of these deficits, although other factors are also under investigation. Consequently, the search for appropriate interventions for the amelioration of these deficits has dominated the literature …

Detection Of Tinnitus In Cba/Caj Mice Using The Active Avoidance Shuttle Box Test, Grace Nichols

University Scholar Projects

Tinnitus is a neurological condition that involves the perception of a sound that is not actually there. Individuals affected with tinnitus describe the condition as a ringing, buzzing, or whooshing sound in their ears. One-third of the population is estimated to have tinnitus, and for many individuals, the condition negatively impacts quality of life. Difficulty falling asleep, trouble with hearing and concentrating, and in some cases, depression, have all been observed to occur with tinnitus.

Tinnitus has been extensively studied in animals, and behavioral tests are the primary method of evaluating the presence of tinnitus in animals. This study evaluates …

Deficiency Of Complement Component C1q Prevents Cerebrovascular Damage And White Matter Loss In A Mouse Model Of Chronic Obesity., Leah C Graham, Heidi E Kocalis, Ileana Soto Reyes, Gareth R Howell

College of Science & Mathematics Departmental Research

Age-related cognitive decline and many dementias involve complex interactions of both genetic and environmental risk factors. Recent evidence has demonstrated a strong association of obesity with the development of dementia. Furthermore, white matter damage is found in obese subjects and mouse models of obesity. Here, we found that components of the complement cascade, including complement component 1qa (C1QA) and C3 are increased in the brain of Western diet (WD)-fed obese mice, particularly in white matter regions. To functionally test the role of the complement cascade in obesity-induced brain pathology, female and male mice deficient in C1QA, an essential molecule in …

Language, Motor, And Cognitive Outcomes Of Toddlers Who Were Born Preterm, Diane Frome Loeb, Caitlin M. Imgrund, Jaehoon Lee, Steven Barlow

Center for Brain, Biology, and Behavior: Faculty Publications

Purpose: The purpose of this study was to examine the language, motor, and cognitive abilities of children born preterm in four categories: (a) healthy preterm infants, (b) infants of diabetic mothers, (c) infants with respiratory distress syndrome, and (d) infants with chronic lung disease when the children were 30 months, uncorrected age. Comorbidity of language, motor, and cognitive skills was examined, along with predictor variables.

Method: A total of 148 children who were born preterm participated and were assessed using bivariate tests and logistic regression on standardized assessment scores.

Results: Controlling for the children’s gestational age (GA), overall language ability …

Reorganization Of The Human Ventricular-Subventricular Zone Neural Stem Cell Niche In Fetal-Onset Hydrocephalus, Saurabh Kumar

University Scholar Projects

Fetal-onset hydrocephalus is a relatively common birth defect occurring in 1-2 cases per thousand births and is characterized by abnormally expanded brain ventricles. Current diagnosis for this complex pathology often involves relatively simple metrics and heavy reliance on clinician experience over objective measures. Those affected often suffer chronic headaches and cognitive deficits and may present with a bulging skill. Shunting is considered the standard treatment for communicating hydrocephalus (i.e. cerebrospinal fluid flow is physically unobstructed in the ventricular system). Shunting remains a highly invasive procedure often performed during the critical period of infancy and has a high failure rate of …

Formation, Organization, And Synaptic Properties Of Circuits Between Thalamic Reticular Nucleus And Dorsal Lateral Geniculate Nucleus., Peter W. Campbell

Electronic Theses and Dissertations

The thalamic reticular nucleus (TRN) is an interface between thalamus and cortex that regulates thalamocortical rhythms and modulates sensory processing. Thalamocortical axon collaterals provide feedforward excitatory input onto GABAergic TRN neurons, which in turn convey feedback inhibition to dorsal thalamus. Here we used the mouse visual system to study the organization, pattern of innervation and functional responses between TRN and the dorsal lateral geniculate nucleus (dLGN). We used genetically modified mice to target components of this feedback loop (feedforward: CRH-Cre; feedback: GAD65 or SST-Cre) and we created Math 5^-/- strains to examine the impact of visual deaffrentation in these …

Detection Of Tinnitus In Cba/Caj Mice Using The Active Avoidance Shuttle Box Test, Grace Nichols

Honors Scholar Theses

Tinnitus is a neurological condition that involves the perception of a sound that is not actually there. Individuals affected with tinnitus describe the condition as a ringing, buzzing, or whooshing sound in their ears. One-third of the population is estimated to have tinnitus, and for many individuals, the condition negatively impacts quality of life. Difficulty falling asleep, trouble with hearing and concentrating, and in some cases, depression, have all been observed to occur with tinnitus.

Tinnitus has been extensively studied in animals, and behavioral tests are the primary method of evaluating the presence of tinnitus in animals. This study evaluates …

Amygdala And Neocortical Structural Volume Analysis In The Shank3b Mutant Mouse Model Of Autism Spectrum Disorder, Preet Sawhney

Honors Scholar Theses

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder that is characterized by abnormal social behavior, deficits in communication, and motor stereotypy. The SHANK3 gene, responsible for the generation of a scaffolding protein that is integral for the development of synapses, has been identified as one of the primary candidate genes implicated in the disorder. Shank3B is the rodent homolog for this gene. Research has shown that when this gene is disrupted in rodent models (e.g., via knock-out (KO)), ASD-like behaviors result. These include deficits in social interaction, increased anxiety, and repetitive self-grooming. The current study aimed to identify a physiological …

Microglia-Neuron Interactions In A Mouse Model Of Low Grade Neuroepithelial Tumors, Veolette Hanna

Honors Scholar Theses

Microglia are the macrophages of the brain and spinal cord, playing an important role in the immune response to disease states of the nervous system. This study conducts an investigation on the activity of microglia in response to low grade neuroepithelial tumors. Using mouse models and microglial markers, a qualitative and quantitative analysis of microglia activation, migration, and invasion within the brain cortex during early stages of tumor development was conducted. It was found that the presence of a low grade neuroepithelial tumor in the cortex of one hemisphere of the brain causes significant microglia activation in comparison to the …

Anxiety And How To Control It: The Functional Role Of The Bed Nucleus Of The Stria Terminalis., Lindsay K. Knight

Electronic Theses and Dissertations

Anxiety disorders afflict up to one third of the population. Research to date has primarily focused on the amygdala, however, new perspectives suggest that a tiny basal forebrain region known as the bed nucleus of the stria terminalis (BNST) may hold key insights into understanding and treating anxiety disorders. Therefore, my first aim was to empirically investigate the importance and influence of the BNST in anxiety processing. Using fearful faces and human screams as aversive stimuli, two threat conditions were created: one in which threats were certain and predictable (fear) and another in which threats were uncertain and unpredictable (anxiety). …

Screen Usage Relates To Neuroanatomy Underlying Reward Processing., Lucus Kiger Hodge

College of Arts & Sciences Senior Theses

Today’s world is inundated with technology and our use of screens. It is possible that screen usage might affect the structural development of brain systems underlying motivation, reward, and addiction. Two hundred and thirty-two 10-year-old individuals’ structural MRI and behavioral data from a publicly accessible database were analyzed to find relations between the cortical and subcortical regions of the reward circuits of the brain and the usage of social media, texting, television, YouTube and other video applications, video games, and video chat applications. Both cortical and subcortical results yielded significant relationships with variables of screen time usage. Most significantly, subcortical …

Cardiomyocyte Morphology Following Severe Spinal Cord Contusion In Rodents., Addison D. Riney

College of Arts & Sciences Senior Theses

Spinal cord injury (SCI) is typically a traumatic event that impacts a patient's physical, psychological, and social well-being by damaging motor and sensory neurons and altering autonomic function leading to cardiac remodeling ⁽⁴²⁾. Spinal cord injuries are based on a scale of severity, with severe, high-level lesions strongly correlating to the degree of cardiovascular dysfunction. ^(30)(37)(41). The decline in cardiovascular function is prevalent after high thoracic SCI, with patients suffering from daily bouts of orthostatic hypotension (OH) and autonomic dysreflexia (AD), both of which prevent and delay rehabilitation efforts and lessen quality of life after …