Medical Neurobiology Commons^™

Acute And Chronic Effects Of Neuroinflammation On Hippocampus And Anterior Cingulate Cortex Network Dynamics, Lauren A. Crew

UNLV Theses, Dissertations, Professional Papers, and Capstones

Neuroinflammation has emerged as a critical modulator of cognitive function and neural circuit dynamics, yet the distinct contributions of acute and chronic neuroinflammation to brain function remain poorly defined. This dissertation examines how inflammation independently alters large-scale neural activity and behavior, focusing on interactions between the hippocampus (HPC) and anterior cingulate cortex (ACC), regions essential for memory and executive processes. Using in vivo electrophysiological techniques in a rodent model, this study compares the effects of short-term (acute) and prolonged (chronic) neuroinflammatory states, induced via Poly I:C, on neural oscillations, regional coherence, and spatial coding. Findings reveal that even transient inflammation …

Estradiol Signaling Improves Extinction Memory Recall To Combat Cue-Induced Heroin Relapse In Rats, Jordan S. Carter

MUSC Theses and Dissertations

We are in the midst of an opioid use disorder (OUD) epidemic. While several treatments mitigate a range of factors contributing to return to use, or relapse, the power of drug-conditioned environmental cues to precipitate relapse have not been adequately addressed. One treatment modality targeting cue reactivity, cue exposure therapy (CET), exacerbated relapse in individuals with OUD, perhaps due to a deficit in extinction memory recall (EMR). Here, EMR is the ability to override the drug-cue association and prevent relapse. Interest remains in combatting cue-induced relapse, potentially by introducing a pharmacologic adjunct with CET to enhance EMR. In the following …

Nursing Considerations For Post-Traumatic Amnesia After A Traumatic Brain Injury, Hannah Grant

Senior Honors Theses

A period known as post-traumatic amnesia (PTA) often follows a traumatic brain injury (TBI). PTA is characterized by anterograde and retrograde amnesia, confusion, disorientation, and agitation. The duration and severity of PTA is a key indicator of the long-term prognosis after a TBI, so proper assessment and nursing care of a PTA patient is crucial. TBIs range from mild to severe, but primarily affect the fronto-temporal lobes. In PTA, both neural lesions and white matter damage within the parahippocampal region can cause PTA. A nurse must perform a thorough assessment of a TBI patient, but, since PTA is a key …

Computational Analysis Of Memory Consolidation Following Inhibitory Avoidance (Ia) Training In Adult And Infant Rats: Critical Roles Of Camkiia And Mecp2, Yili Zhang, Paul Smolen, Cristina M Alberini, Douglas A Baxter, John H Byrne

Faculty, Staff and Student Publications

Key features of long-term memory (LTM), such as its stability and persistence, are acquired during processes collectively referred to as consolidation. The dynamics of biological changes during consolidation are complex. In adult rodents, consolidation exhibits distinct periods during which the engram is more or less resistant to disruption. Moreover, the ability to consolidate memories differs during developmental periods. Although the molecular mechanisms underlying consolidation are poorly understood, the initial stages rely on interacting signaling pathways that regulate gene expression, including brain-derived neurotrophic factor (BDNF) and Ca²⁺/calmodulin-dependent protein kinase II α (CaMKIIα) dependent feedback loops. We investigated the ways …

Brain Development: Why The Young Sleep Longer, Budhaditya Chowdhury, Orie T. Shafer

Advanced Science Research Center

From absorbing new languages to mastering musical instruments, young children are wired to learn in ways that adults are not (Johnson and Newport, 1989). This ability coincides with periods of intense brain plasticity during which neurons can easily remodel their connections (Hubel and Wiesel, 1970). Many children are also scandalously good sleepers, typically getting several more hours of sleep per night than their parents (Jenni and Carskadon, 2007). As sleep deprivation has negative effects on learning and memory, learning like a child likely requires sleeping like one (Diekelmann and Born, 2010). Yet, how the ability to sleep for longer is …

Prefrontal Corticotropin-Releasing Factor (Crf) Neurons Act Locally To Modulate Frontostriatal Cognition And Circuit Function., Sofiya Hupalo, Andrea J Martin, Rebecca K Green, David M Devilbiss, Craig W Berridge

Rowan-Virtua School of Osteopathic Medicine Departmental Research

The PFC and extended frontostriatal circuitry support higher cognitive processes that guide goal-directed behavior. PFC-dependent cognitive dysfunction is a core feature of multiple psychiatric disorders. Unfortunately, a major limiting factor in the development of treatments for PFC cognitive dysfunction is our limited understanding of the neural mechanisms underlying PFC-dependent cognition. We recently demonstrated that activation of corticotropin-releasing factor (CRF) receptors in the caudal dorsomedial PFC (dmPFC) impairs higher cognitive function, as measured in a working memory task. Currently, there remains much unknown about CRF-dependent regulation of cognition, including the source of CRF for cognition-modulating receptors and the output pathways modulated …

Defining The Radioresponse Of Mossy Cells, Devon Ivy

Electronic Theses, Projects, and Dissertations

Clinical radiotherapy is used to treat a variety of brain tumors within the central nervous system. While effective, it can result in progressive and debilitating cognitive impairment that can diminish quality of life. These impairments have been linked to hippocampal dysfunction and corresponding deficits in spatial learning and memory. Mossy cells are a major population of excitatory neurons located within the dentate hilus and highly involved in hippocampal circuitry. They play critical roles in spatial navigation, neurogenesis, memory, and are particularly vulnerable to a variety of neurotoxic insults. However, their sensitivity to ionizing radiation has yet to be investigated in …

Exercise, Learning And Emotional Health: Interdisciplinary Approaches To Translational Action, Tessa L. Koschel

UNLV Theses, Dissertations, Professional Papers, and Capstones

Exercise positively effects physical, psychological and neurological wellbeing. Though the population at large is becoming increasingly aware of the multi-faceted benefits of exercise, the majority of people fail to meet daily exercise recommendations. Largely, demands of everyday life such as work, school and family take priority over fitness. The issue therefore becomes a matter of time. In a world of media multi-tasking and immediate gratification, the challenge to health professionals becomes incorporation and manipulation of these consistencies to improve exercise uptake and adherence. Focus must shift from the idea of making additional time for exercise, to adding exercise to time …

Thujone Inhibits The Function Of Α7-Nicotinic Acetylcholine Receptors And Impairs Nicotine-Induced Memory Enhancement In One-Trial Passive Avoidance Paradigm, Ahmed Sultan, Keun-Hang Susan Yang, Dmytro Isaev, Eslam El Nebrisi, Nurulain Syed, Nadia Khan, Christopher F. Howarth, Bassem Sadek, Murat Oz

Mathematics, Physics, and Computer Science Faculty Articles and Research

Effects of thujone, a major ingredient of absinthe, wormwood oil and some herbal medicines, were tested on the function of α7 subunit of the human nicotinic acetylcholine (α7 nACh) receptor expressed in Xenopus oocytes using the two-electrode voltage-clamp technique. Thujone reversibly inhibited ACh (100 μM)-induced currents with an IC50 value of 24.7 μM. The effect of thujone was not dependent on the membrane potential and did not involve Ca2+-dependent Cl- channels expressed endogenously in oocytes. Inhibition by thujone was not reversed by increasing ACh concentrations. Moreover, specific binding of [125I] -bungarotoxin was not altered by thujone. Further experiments in SH-EP1 …

Differential Involvement Of Hippocampal Angiotensin 1 Receptors In Learning And Memory Processes In Bulbectomized Rats, Roman Tashev, Margarita Ivanova, Stiliana Belcheva, Iren Belcheva

Journal of Mind and Medical Sciences

There is conflicting evidence regarding the effect of AT1 receptor antagonists on learning and memory processes. The effects of angiotensin II and losartan administration into CA1 hippocampal area on the avoidance performance in olfactory bulbectomized (OBX) rats using active avoidance (shuttle box) test and passive avoidance (step through) test were investigated. Rats were microinjected unilaterally through implanted guide cannulas into the CA1 area of the dorsal hippocampus and the drugs were administered separately, 5 minutes before each training session. The microinjections of losartan into the left, but not the right CA1 hippocampal area improved the acquisition and retention of active …

Associations Between Cadmium Exposure And Neurocognitive Test Scores In A Cross-Sectional Study Of Us Adults, Timothy Ciesielski, David C. Bellinger, Joel Schwartz, Russ Hauser, Robert O. Wright

Dartmouth Scholarship

Background: Low-level environmental cadmium exposure and neurotoxicity has not been well studied in adults. Our goal was to evaluate associations between neurocognitive exam scores and a biomarker of cumulative cadmium exposure among adults in the Third National Health and Nutrition Examination Survey (NHANES III).

Methods: NHANES III is a nationally representative cross-sectional survey of the U.S. population conducted between 1988 and 1994. We analyzed data from a subset of participants, age 20–59, who participated in a computer-based neurocognitive evaluation. There were four outcome measures: the Simple Reaction Time Test (SRTT: visual motor speed), the Symbol Digit Substitution Test (SDST: attention/perception), …

The Effect Of Spiritualism On The Neuropsychological Function Of Memory, Carla Farcello

McNair Poster Presentations

The amount of physiological-neurological research performed over the past few years has dramatically increased due to our ability to view the structure and function of the brain in living human beings. The use of imaging tools has resulted in huge strides forward in unlocking some of the mysteries of the 3 pound universe-the human brain. One of the more unique neural processes being recently addressed is the affect of belief and spiritualism-the sense of being connected to something larger than oneself-on the human brain. This study hypothesized that better memory will be documented among the experimental group who report being …

Abeta42 Mutants With Different Aggregation Profiles Induce Distinct Pathologies In Drosophila., Koichi Iijima, Hsueh-Cheng Chiang, Stephen A Hearn, Inessa Hakker, Anthony Gatt, Christopher Shenton, Linda Granger, Amy Leung, Kanae Iijima-Ando, Yi Zhong

Department of Biochemistry and Molecular Biology Faculty Papers

Aggregation of the amyloid-beta-42 (Abeta42) peptide in the brain parenchyma is a pathological hallmark of Alzheimer's disease (AD), and the prevention of Abeta aggregation has been proposed as a therapeutic intervention in AD. However, recent reports indicate that Abeta can form several different prefibrillar and fibrillar aggregates and that each aggregate may confer different pathogenic effects, suggesting that manipulation of Abeta42 aggregation may not only quantitatively but also qualitatively modify brain pathology. Here, we compare the pathogenicity of human Abeta42 mutants with differing tendencies to aggregate. We examined the aggregation-prone, EOFAD-related Arctic mutation (Abeta42Arc) and an artificial mutation (Abeta42art) that …