Neuroscience and Neurobiology Commons^™

How To Search For The Engram: Optogenetics And Network Dynamics, Claudia Garcia Jou

Dissertations, Theses, and Capstone Projects

Memories are thought to be encoded by ensembles of neurons called "engram cells", because their artificial activation with optogenetics leads to the behavioral expression of a memory. However, the physiological mechanisms that mediate this process remain unknown. In this thesis, I investigate how optogenetic stimulation of memory-tagged cells changes neuronal firing, spatial coding, and the geometry of neural manifolds. I used an active place avoidance task and a foraging task to label engram cells in the dorsal hippocampus with Channelrhodopsin2 (ChR2). I then recorded the hippocampal activity response to optogenetic stimulation in mice under anesthesia, head-fixed, or freely moving. I …

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 …

A Natural Short Sleep Mutation Promotes Longevity Through Mitochondrial Respiration In Drosophila, Pritika Pandey

LSU Doctoral Dissertations

Aging is an irreversible process characterized by progressive physiological decline and an increased risk of metabolic disorders, cognitive impairment, cardiovascular diseases, and neurodegeneration. Disruptions to the circadian clock—whether due to genetic mutations or behavioral factors—accelerate aging and age-related pathologies, highlighting a strong link between circadian regulation and longevity. However, certain individuals harbor a dec2^P384R mutation, which enables natural short sleep without the detrimental effects of chronic sleep deprivation. This suggests that these individuals have evolved adaptations that activate pro-health pathways, allowing them to function optimally with reduced sleep. To investigate the genetic mechanisms underlying these changes, we developed a …

Hippocampal Insulin Exists! In Vivo Sampling Methods, Basal Concentrations, Recurrent Hypoglycemia, And Behavioral Extracellular Insulin Responses, Starlette R. Douglass

Electronic Theses & Dissertations (2024 - present)

Insulin has widespread actions within the brain, including energy homeostasis, modulation of feeding, and as a key component of memory processes. Further, brain insulin dysfunction correlates with Alzheimer's disease and other neurodegenerative disorders. To this point, measurement of hippocampal insulin has been limited. Determining in vivo hippocampal insulin levels both at a healthy baseline and after, e.g., induction of a disease state or in response to cognitive challenge, is essential to advance our understanding of both insulin's procognitive actions and to guide potential therapeutic interventions.

We first sought to establish a sampling technique for insulin within awake and moving rats …

The Effect Of Exercise Type On Working Memory, Ariana Gonzalez, William R. Kochen

Journal for Sports Neuroscience

Martial arts encompass a wide range of sports and techniques that have been practiced for self-defense and combat for thousands of years. It has expanded to include various styles such as Brazilian Jiu-Jitsu, Taekwondo, judo, and karate. It has also been practiced as a form of exercise and entertainment. Martial arts have been associated to discipline, integrity, improved stamina, and increased mental and problem-solving capabilities. Unlike other exercise methods, most martial arts require focus, skill, and technique, which have been hypothesized to improve memory. The purpose of the study was to determine if there was a significant improvement in the …

Memory Modulation: Dominance Of Negative Visual Context Over Neutral Verbal Memory, Stas Kozak, Noa Herz, Maya Tocker, Yair Bar-Haim, Nitzan Censor

Department of Neurology Faculty Papers

Neutral memories can be modulated via intentional memory control paradigms such as directed forgetting. In addition, previous studies have shown that neutral visual memories can be modulated indirectly, via remember and forget instructions towards competing verbal memories. Here we show that direct modulation of neutral verbal memory strength is impaired by negative visual context, and that negative visual context is resistant to indirect memory modulation. Participants were directly instructed to intentionally remember or forget newly encoded neutral verbal information. Importantly, this verbal information was interleaved with embedded negative visual context. Results showed that negative visual context eliminated the well-documented effect …

Effects Of Vitis Vinifera L. Seed Extract On Short-Term Memory Of Amyloid-Beta-Mediated Neurodegeneration In Transgenic Caenorhabditis Elegans, Elise Patrick

Theses

Alzheimer's disease (AD) is a neurodegenerative condition that is a common cause of dementia and a growing concern worldwide with no effective treatment or cure. Two pathological AD hallmarks include buildup of amyloid beta (Aβ) plaques and neurofibrillary tangles in the brain. Recent attention has turned to exploring natural products and compounds for AD symptom relief and treatment. Vitis vinifera grape seed extract (GSE) contains many beneficial substances. GSE has been tested in several animal models and has shown to improve memory and is even being examined in an AD treatment human clinical trial. In this study, the aim was …

Effects Of Transcranial Direct Current Stimulation On Metamemory Vary By Task Difficulty, Tiffanie T. Li

Dissertations, Theses, and Capstone Projects

Metamemory is broadly defined as the awareness of one’s memory and consists, in part, of a process referred to as monitoring, where one is assessing the contents of their memory. Feeling of knowing (FOK) is one metamemory monitoring judgment where one rates how strongly they believe they will remember a currently unrecalled item. Prior work has shown that HighDefinition Transcranial Direct Current Stimulation (HD-tDCS) over the dorsal lateral prefrontal cortex (DLPFC) led to greater metamemory accuracy and that HD-tDCS over the anterior temporal lobe (ATL) led to better recall for medium difficulty questions. Other work has also shown that effects …

The Neural Sequalae Of Subjectively Experiencing Autobiographical Memories From The Remote Past And Recent Present Using Fmri, Ava G. Peruski, Nim Singh, Brendan E. Depue

The Cardinal Edge

Autobiographical memory is central to one's sense of self and continuity from past to present. Despite this, there is little research on the neural correlates underlying individual subjective experience of autobiographical memory and how that is related to brain phenomena (i.e., activity, communication). The purpose of this study was to help minimize this gap. We recruited twenty healthy adult participants, who were asked to generate memory cues (1-3 word descriptions) for locations and objects from their early and recent life. After 24 hours, participants were shown these cues then asked to recall the appropriate memory while in an fMRI scanner. …

Functional Network Reconfiguration Supporting Memory-Guided Attention, Kylie Isenburg, Thomas M. Morin, Maya L. Rosen, David C. Somers, Chantal E. Stern

Neuroscience: Faculty Publications

Studies have identified several brain regions whose activations facilitate attentional deployment via long-term memories. We analyzed task-based functional connectivity at the network and node-specific level to characterize large-scale communication between brain regions underlying long-term memory guided attention. We predicted default mode, cognitive control, and dorsal attention subnetworks would contribute differentially to long-term memory guided attention, such that network-level connectivity would shift based on attentional demands, requiring contribution of memory-specific nodes within default mode and cognitive control subnetworks. We expected that these nodes would increase connectivity with one another and with dorsal attention subnetworks during long-term memory guided attention. Additionally, we …

The Effects Of Acute Exercise On Memory: Considerations Of The Testing Effect, Philip Christian

Honors Theses

This study had three main objectives. The first objective was to determine whether or not there was evidence of a testing effect being present when a short-term memory assessment is included along with a long-term memory assessment. The second objective was to determine whether acute exercise can improve long-term memory recall over a control condition. The third objective was to determine if the potential effects of acute exercise on long-term memory are confounded by the inclusion of a short-term memory assessment. Participants were 54 undergraduate students at the University of Mississippi, with an age range of 18-22 years old. Participants …

Consequences Of Environment And Loss On Maternal Behavior, Anxiety, Boldness, And Memory In Rats, Alayna Skye Palamar

Longwood Senior Thesis Proposal

No abstract provided.

Accelerated Forgetting In People With Epilepsy: Pathologic Memory Loss, Its Neural Basis, And Potential Therapies, Sarah Ashley Steimel Phd

Dartmouth College Ph.D Dissertations

While forgetting is vital to human functioning, delineating between normative and disordered forgetting can become incredibly complex. This thesis characterizes a pathologic form of forgetting in epilepsy, identifies a neural basis, and investigates the potential of stimulation as a therapeutic tool. Chapter 2 presents a behavioral characterization of the time course of Accelerated Long-Term Forgetting (ALF) in people with epilepsy (PWE). This chapter shows evidence of ALF on a shorter time scale than previous studies, with a differential impact on recall and recognition. Chapter 3 builds upon the work in Chapter 2 by extending ALF time points and investigating the …

Multilingualism And Memory: Investigating Possible Differences In The Abilities Of Monolingual And Multilingual College Students, Clara E. Barned

Honors Projects

This study investigated whether there is a difference in the memories of monolingual and multilingual undergraduate students using simple memorization tasks. There were 46 participants, 30 of which were monolingual (only knew one language) and 16 of which were multilingual (knew two or more languages). There was found to be no significant difference between the performance of the two groups, with the data generating a p-value of 0.557. This study further suggests related avenues of research and ways in which the study could be improved in the future.

The Effects Of Floral Attributes And Conspecifics On Bumble Bee Forager Memory, Lucas Lauter, Tiffany Dinh

Undergraduate Research Symposium

What do bees remember about flowers? These memories are important for both bees and flowers. The bees have better foraging success and gain more nectar and pollen from flowers when they remember the most rewarding flower types. More memorable flowers will be visited more frequently, resulting in more successful pollination for the plant. At the same time, bees can also learn about flowers from other bees and may remember this information differently. We are training and testing three floral cues and a single social cue to see how the different types of cues affect their learning and memory of rewarding …

The Effects Of Acute Exercise Intensity On Retrieval-Induced Forgetting, Geoffrey Reliquias

Honors Theses

Previous research has indicated that aspects of cognitive inhibition may be enhanced after engaging in acute exercise. Notably, cognitive inhibition has been theorized as a potential mechanism for a form of active forgetting known as retrieval-induced forgetting (RIF). Given that cognitive inhibition may explain the RIF phenomenon, and is also influenced by exercise, it is plausible that acute exercise may directly influence RIF. To our knowledge, only one study has examined whether acute exercise has an effect on RIF. The findings of that study did not find a statistically significant effect for RIF; however, we believe that the rather small …

Effects Of Music Exposure On Autobiographical Memory In Alzheimer's Patients: A Systematic Review And Meta-Analysis, Gregory Vance

Honors Theses

The progression of Alzheimer’s disease is primarily characterized by a loss of memory concerning past events, as well as a lack in ability to create new memories. While this spans across many subsets of memory, such as recognition, recall, and autobiographical memory, there seems to be a lesser impact on musical memory in those with Alzheimer’s. Multiple studies have suggested that exposure to music and introduction of music therapy can even improve other aspects of memory in Alzheimer’s patients. This systematic review and meta-analysis sought to examine the relationship between music exposure and autobiographical memory specifically. A pool of electronic …

Flashbulb Memories Among College Students During Covid-19, Sabah Qureshi

Honors Undergraduate Theses

Flashbulb memories are formed through widely shared events that have affected the culture and community. The “flash” in flashbulb memories refers to the specific details that individuals have developed in their memories. The presented research focuses on the specific event of college students at the University of Central Florida (UCF) hearing about university closure due to the COVID-19 pandemic. This research study sought to identify the variables that have affected the accuracy of flashbulb memories formation regarding the event of college students hearing about university closure because of the pandemic. The variables of the students’ relevance to the university, location, …

Neural Correlates And Neuroanatomy Of Juvenile And Adult Contextual Fear Memory Retention, Natalie Odynocki

Legacy Theses & Dissertations (2009 - 2024)

AbstractFear is an evolutionarily conserved mechanism that allows an organism to discern potential harm and act accordingly by engaging in defensive behaviors. While fear is an adaptive response, dysregulation of fear by means of a traumatic event can lead to psychiatric conditions such as post-traumatic stress disorder (PTSD). Animal research using rodents in Pavlovian context fear conditioning experiments allows for the ability to study the underlying neural circuitry of threat-appropriate and aberrant fear learning and memory that may contribute to PTSD. However, despite reports that women are more than two times more likely to develop PTSD compared to men, the …

The Giver: Vision & Memory, Alexander J. Dontre

All Faculty and Staff Scholarship

A memory hole is the banishment of problematic thoughts. We exile that which we prefer not to exist. Enter the perilous Memory Hole: The Psychology of Dystopia, to explore a legion of social and psychological themes through the lens of dystopian literature. The crushing fist of 1984 annihilating thoughts from existence as a means of persuasion. The exquisite seduction of addiction as an agent of control in Brave New World. Incineration of the written word to bask in the embers of peace of mind in Fahrenheit 451. Each chapter weaves in and out of the dystopian realms forged …

Long-Term Neural Activity Recorders Using Energy-Based Sensing, Compressive Computation And Data Logging, Darshit Mehta

McKelvey School of Engineering Graduate Student Theses & Dissertations

Insects are ideal candidates for developing bio-robotic systems owing to their ability to thrive in almost any environment. For example, neurons in their exquisite olfactory sensory systems can be tapped to create a sensing platform for standoff chemical monitoring. However, for enabling such cyborg systems, it is vital that the neural activity of a freely behaving organism can be measured for long periods of time. The current state-of-the-art neural recording techniques are power-intensive and they either need batteries, which make them too bulky for insects, or they have to maintain a continuous telemetry link to an external power source which …

The Role Of The Dal Neurons In Modulating Circadian Rhythms In Olfactory Short-Term Memory In Drosophila Melanogaster, Cooper Ruwe

Honors Theses

Depressed short-term memory (STM) abilities during non-adaptive times of the day can significantly impact those who work occupations that require peak levels of cognitive functioning around the clock. While much work has gone into understanding the endogenous clock and circadian rhythms, there is still much to learn about the neural circuity that underlies the daily rhythms that define these regular oscillations in STM performance. The DAL neurons in the Drosophila brain are part of the circadian network and innervate the mushroom bodies (MBs), the species’ olfactory learning center, making them compelling candidates to be involved in circadian circuitry for olfactory …

Cognitive Abilities In Hearing Loss: Perceived And Performance Abilities Of Adults Related To Attention, Memory, And Social Cognition, Karah Gottschalk

Theses and Dissertations--Gerontology

Hearing loss is the most common sensory deficit noted in aging adults. It is commonly known to reduce an individual’s ability to detect, identify, and localize sounds and speech and to cause issues in communication. However, there are other less commonly discussed impacts that hearing loss has beyond the auditory system. Literature suggests a correlation between hearing loss and cognition in aging adults. Similar to hearing loss, the domains of cognition experience performance and functional changes across the life span. In an aging adult, changes related to cognition are also suggested to be associated with hearing loss. This study aimed …

Investigating The Role Of Attention And Memory In Visual Exploration, Jacob E. Suffridge

Graduate Theses, Dissertations, and Problem Reports (ETD)

This research investigates the role that attention and memory plays in visual exploration through a comprehensive analysis of eye movement and behavioral data, alongside incorporation of a computational saliency model. The purpose of this project is to quantify differences in visual attention over repeated viewings of natural scene images by employing a free viewing task that contains a memory component. In Chapter 2, we explore the task’s behavioral data showing that participants generally memorize our images well before we investigate the effect of numerous object and individual feature inclusion. In Chapter 3, we develop four primary methods to quantify visual …

Core Neuropsychological Measures For Obesity And Diabetes Trials: Initial Report, Kimberlee D'Ardenne, Cary R. Savage, Dana Small, Uku Vainik, Luke E. Stoeckel

Center for Brain, Biology, and Behavior: Faculty Publications

Obesity and diabetes are known to be related to cognitive abilities. The Core Neuropsychological Measures for Obesity and Diabetes Trials Project aimed to identify the key cognitive and perceptual domains in which performance can influence treatment outcomes, including predicting, mediating, and moderating treatment outcome and to generate neuropsychological batteries comprised of well-validated, easy-to-administer tests that best measure these key domains. The ultimate goal is to facilitate inclusion of neuropsychological measures in clinical studies and trials so that we can gather more information on potential mediators of obesity and diabetes treatment outcomes. We will present the rationale for the project and …

An Eeg Study On Loneliness And Recognition Memory, Carmen Jia Wen Chek

Electronic Theses and Dissertations

Loneliness, the perception of unmet social needs, has been shown to relate to recollection-based recognition deficits, but the relationship between loneliness and recognition memory (i.e., recollection and familiarity) has not been thoroughly examined. The current study hypothesized that more lonely individuals would have lower recognition memory performance, specifically recollection, with smaller ERP parietal old-new effects than less lonely individuals. Forty participants, grouped into less (n = 13) and more (n = 9) lonely groups based on their R-UCLA responses, completed an associative memory task. EEG was used to assess recognition memory effects. Results showed no significant difference in …

Males With Chronic Ankle Instability Demonstrate Deficits In Neurocognitive Function Compared To Control And Copers, Adam B. Rosen, Melanie L. Mcgrath, Arthur C. Maerlender

Center for Brain, Biology, and Behavior: Faculty Publications

The purpose of this study was to determine if there were neurocognitive deficits among controls, copers and those with chronic ankle instability (CAI). Participants included those without history of ankle injury (n = 14), ankle sprain copers (n = 13) and patients with self-reported CAI (n = 14). They completed a battery of valid and reliable computer-based neurocognitive tests. The differences between neurocognitive domain scores were compared across the Control, Coper and CAI groups. Patients with CAI had lower composite memory, visual memory and simple attention compared to controls. In males with CAI, large differences in memory and attention were …

What Makes An Image Memorable? Effects Of Encoding On The Mechanism Of Recognition, Asiya Gul

Theses and Dissertations (Comprehensive)

Memory is undoubtedly one of the most important processes of human cognition. A long line of research suggests that recognition relies on the assessment of two explicit memory phenomena: familiarity and recollection. Researchers who support the Dual Process Signal Detection (DPSD) model of recognition memory link the FN400 component (a negative ERP deflection peaking around 400 ms at frontal electrodes) with familiarity; however, it is currently unclear whether the FN400 reflects familiarity or implicit memory. Three event-related potentials (ERP) studies were conducted to determine whether implicit memory plays a role in setting up encoding strategies, and how these encoding strategies …

Distinct Aspects Of The Early Environment Contribute To Associative Memory, Cued Attention, And Memory-Guided Attention: Implications For Academic Achievement, Maya L. Rosen, Andrew N. Meltzoff, Margaret A. Sheridan, Katie A. Mclaughlin

Neuroscience: Faculty Publications

Childhood socioeconomic status (SES) is associated with numerous aspects of cognitive development and disparities in academic achievement. The specific environmental factors that contribute to these disparities remain poorly understood. We used observational methods to characterize three aspects of the early environment that may contribute to SES-related differences in cognitive development: violence exposure, cognitive stimulation, and quality of the physical environment. We evaluated the associations of these environmental characteristics with associative memory, cued attention, and memory-guided attention in a sample of 101 children aged 60–75 months. We further investigated whether these specific cognitive abilities mediated the association between SES and academic …

The Influence Of Neural Reward Processing On Memory In Depression, Nathan M. Hager

Psychology Theses & Dissertations

Theories and research suggest that depression involves impaired reward sensitivity and a deficit in memory for rewarding stimuli. Some researchers propose that this memory deficit may result from reduced neural reward sensitivity, which impairs the encoding of reward-related memories, but few studies have directly probed this connection. Such research may benefit from examining the reward positivity (RewP), an event-related potential (ERP) previously linked to reduced reward sensitivity in depression. Undergraduates with high or low self-reported depression completed a task in which they chose one of three doors, revealing a neutral word written in a color which indicated an outcome of …