Neuroscience and Neurobiology Commons^™

Scale-Free Behavioral Dynamics Directly Linked With Scale-Free Cortical Dynamics, Sabrina Jones

Physics Undergraduate Honors Theses

In organisms, an interesting phenomenon occurs in both behavior and neuronal activity: organization with fractal, scale-free fluctuations over multiple spatiotemporal orders of magnitude (1,2). In regard to behavior, this sort of complex structure-- which manifests itself from small scale fidgeting to purposeful, full body movements-- may support goals such as foraging (3-6), visual search (4), and decision making (7,8). Likewise, the presence of this sort of structure in the cerebral cortex in the form of spatiotemporal cascades, coined “neuronal avalanches,” may offer optimal information transfer (9). Thus, when considering the functional relationship between the cerebral cortex and movements of the …

The Effects Of Deletion Of The Cytoplasmic Domain Of Robo3 On Drosophila, Jessie Agcaoili

Biological Sciences Undergraduate Honors Theses

My research project examines how the deletion of the cytoplasmic domain affects the function of Robo3. If Robo3 is signaling repulsion in response to SLIT this activity should require the cytoplasmic domain. I investigated the functional importance of Robo3 by deleting the cytoplasmic domain of Robo3 using a CRISPR-based technique. This modified gene was then injected into Drosophila embryos where it replaced the normal copy of the gene. Embryos expressing the modified version of robo3 in place of normal robo3 were dissected and examined.

Cumulative Lifetime Stressor Exposure Assessed By The Strain Predicts Economic Ambiguity Aversion, Candace M. Raio, Benjamin B. Lu, Michael Grubb, Grant S. Shields, George M. Slavich, Paul Glimcher

Psychological Science Faculty Publications and Presentations

Uncertainty is inherent in most decisions humans make. Economists distinguish between two types of decision-making under non-certain conditions: those involving risk (i.e., known outcome probabilities) and those that involve ambiguity (i.e., unknown outcome probabilities). Prior research has identified individual differences that explain risk preferences, but little is known about factors associated with ambiguity aversion. Here, we hypothesized that cumulative exposure to major psychosocial stressors over the lifespan might be one factor that predicts individuals’ ambiguity aversion. Across two studies (Study 1: n = 58, M_age = 25.7; Study 2: n = 188, M_age = 39.81), we used a …

Contrastive Learning For Unsupervised Auditory Texture Models, Christina Trexler

Computer Science and Computer Engineering Undergraduate Honors Theses

Sounds with a high level of stationarity, also known as sound textures, have perceptually relevant features which can be captured by stimulus-computable models. This makes texture-like sounds, such as those made by rain, wind, and fire, an appealing test case for understanding the underlying mechanisms of auditory recognition. Previous auditory texture models typically measured statistics from auditory filter bank representations, and the statistics they used were somewhat ad-hoc, hand-engineered through a process of trial and error. Here, we investigate whether a better auditory texture representation can be obtained via contrastive learning, taking advantage of the stationarity of auditory textures to …

Psychobiology Of Stress And Adolescent Depression (Psy Sad) Study: Protocol Overview For An Fmri-Based Multi-Method Investigation, Stassja Sichko, Theresa Q. Bui, Meghan Vinograd, Grant S. Shields, Krishanu Saha, Suzanne Devkota, Hector A. Olvera-Alvarez, Judith E. Carroll, Steven E. Cole, Michael R. Irwin, George M. Slavich

Psychological Science Faculty Publications and Presentations

Depression is a common, often recurrent disorder that causes substantial disease burden worldwide, and this is especially true for women following the pubertal transition. According to the Social Signal Transduction Theory of Depression, stressors involving social stress and rejection, which frequently precipitate major depressive episodes, induce depressive symptoms in vulnerable individuals in part by altering the activity and connectivity of stress-related neural pathways, and by upregulating components of the immune system involved in inflammation. To test this theory, we recruited adolescent females at high and low risk for depression and assessed their psychological, neural, inflammatory, and genomic responses to a …

Odor-Evoked Increases In Olfactory Bulb Mitral Cell Spiking Variability, Cheng Ly, Andrea K. Barreiro, Shree Hari Gautam, Woodrow L. Shew

Physics Faculty Publications and Presentations

The spiking variability of neural networks has important implications for how information is encoded to higher brain regions. It has been well documented by numerous labs in many cortical and motor regions that spiking variability decreases with stimulus onset, yet whether this principle holds in the OB has not been tested. In stark contrast to this common view, we demonstrate that the onset of sensory input can cause an increase in the variability of neural activity in the mammalian OB. We show this in both anesthetized and awake rodents. Furthermore, we use computational models to describe the mechanisms of this …

Blood–Brain Barrier Breakdown And Astrocyte Reactivity Evident In The Absence Of Behavioral Changes After Repeated Traumatic Brain Injury, Celeste Dunn, Nasya Sturdivant, Sara Venier, Syed Ali, Jeffery Wolchok, Kartik Balachandran

Biomedical Engineering Faculty Publications and Presentations

Repeated traumatic brain injuries (TBIs) cause debilitating effects. Without understanding the acute effects of repeated TBIs, treatment options to halt further degeneration and damage cannot be developed. This study sought to examine the acute effects of blood–brain barrier (BBB) dysfunction, edema, inflammation and behavioral changes after either a single or double TBI using a C57BL/6 mouse model. We examined the effects of one or two TBIs, of either a mild or moderate severity. Double injuries were spaced 7 days apart, and all analysis was performed 24 h post-injury. To examine edema and inflammation, protein levels of glial fibrillary acidic protein …

The Balance Of Excitation And Inhibition And Its Influence On Cortical States And Rett Syndrome, Jingwen Li

Graduate Theses and Dissertations

Our brain consists of billions of neurons, properly coordinating to process information and realize brain functions. Among them, there are two types of neurons: excitatory neurons and inhibitory neurons. The firing of excitatory neurons increases the membrane potential of downstream neurons, and thus excites other neurons to fire. The firing of inhibitory neurons, in contrast, decreases the membrane potential of downstream neurons, and thus inhibits other neurons to fire. The interplay of excitatory and inhibitory neurons shape the spiking activity in the population. Thus, the `balance of excitation and inhibition' plays an important role in cortical processing and brain functions. …

The Effect Of A Mindfulness-Based Intervention On Attention And Cognitive Control As A Function Of Smartphone Notifications., Joshua D. Upshaw

Graduate Theses and Dissertations

Barriers to accessing mobile technology, particularly smartphones, have decreased substantially since the iPhone’s release in 2007, resulting in increased ownership and usage across all ages, genders, and races. Despite their ubiquity in our society, relatively little empirical work has investigated the influence of smartphones on our higher order executive functioning. Prior work has linked smartphone use with impaired cognitive control during cognitively demanding tasks, especially in heavier smartphone users. The goals of the current study were twofold. First, the study aimed to examine the effects of smartphone notifications on cognitive control and attention. And second, to determine the effects of …

Microfabrication And Electrochemical Characterization Of A Novel Su-8 Probe With An Array Of Individually Addressable Electrodes Suitable For Redox Cycling Experiments In Ultra-Small Volumes, Mahsa Lotfi Marchoubeh

Graduate Theses and Dissertations

Redox cycling is an electrochemical technique that utilizes closely spaced generator and collector electrodes to cycle reversible redox species between their oxidative states. With advantages in signal amplification, selectivity of species based on their electrochemical reaction mechanism, and limited or no background subtraction, this technique is well suited for selective detection of important electrochemically active molecules such as dopamine at basal or slowly changing levels.

Miniaturized medical devices have become an area of great interest for measurement of chemicals in limited volumes with low concentrations or in sensitive tissues. A probe on a polymeric SU-8 substrate with suitable dimensions and …

Action Video Gaming Experience Related To Altered Resting-State Eeg Temporal And Spatial Complexity, Ruifang Cui, Jinliang Jiang, Lu Zeng, Lijun Jiang, Zeling Xia, Li Dong, Diankun Gong, Guojian Yan, Weiyi Ma, Dezhong Yao

General Human Environmental Sciences Faculty Publications and Presentations

Action video gaming (AVG) places sustained cognitive load on various behavioral systems, thus offering new insights into learning-related neural plasticity. This study aims to determine whether AVG experience is associated with resting-state electroencephalogram (rs-EEG) temporal and spatial complexity, and if so, whether this effect is observable across AVG subgenres. Two AVG games – League of Legends (LOL) and Player Unknown’s Battle Grounds (PUBG) that represent two major AVG subgenres – were examined. We compared rs-EEG microstate and omega complexity between LOL experts and non-experts (Experiment 1) and between PUBG experts and non-experts (Experiment 2). We found that the experts and …

Using Deep Learning For Children Brain Image Analysis, Rafael Toche Pizano

Computer Science and Computer Engineering Undergraduate Honors Theses

Analyzing the correlation between brain volumetric/morphometry features and cognition/behavior in children is important in the field of pediatrics as identifying such relationships can help identify children who may be at risk for illnesses. Understanding these relationships can not only help identify children who may be at risk of illnesses, but it can also help evaluate strategies that promote brain development in children. Currently, one way to do this is to use traditional statistical methods such as a correlation analysis, but such an approach does not make it easy to generalize and predict how brain volumetric/morphometry will impact cognition/behavior. One of …

The Influence Of Action Video Gaming Experience On The Perception Of Emotional Faces And Emotional Word Meaning, Yuening Yan, Yi Li, Xinyu Lou, Senqi Li, Yutong Yao, Diankun Gong, Weiyi Ma, Guojian Yan

General Human Environmental Sciences Faculty Publications and Presentations

Action video gaming (AVG) experience has been found related to sensorimotor and attentional development. However, the influence of AVG experience on the development of emotional perception skills is still unclear. Using behavioral and ERP measures, this study examined the relationship between AVG experience and the ability to decode emotional faces and emotional word meanings. AVG experts and amateurs completed an emotional word-face Stroop task prior to (the pregaming phase) and after (the postgaming phase) a 1 h AVG session. Within-group comparisons showed that after the 1 h AVG session, a more negative N400 was observed in both groups of participants, …

How The Covid-19 Pandemic Has Affected Physical Activity, Sleep And Mental Health In University Students, Faculty And Staff And To Examine The Relationship Between These Variables, Zachary Parisi

Health, Human Performance and Recreation Undergraduate Honors Theses

Background: Increased physical activity has been shown to be beneficial in decreasing stress. This project will expand on this knowledge while also studying college students, a demographic that has been less studied. This study will also examine the impact of COVID-19 on these variables. COVID-19 changed many peoples’ activities of daily life, and possibly physically activity levels, due to public health measures such as lockdowns and remote learning. Purpose: The purpose of this study is to examine how the COVID-19 pandemic has affected physical activity, sleep, and mental health in university students, faculty and staff and to examine the relationship …

Reduced Adaptation Of Glutamatergic Stress Response Is Associated With Pessimistic Expectations In Depression, Jessica A. Cooper, Makiah R. Nuutinen, Victoria M. Lawlor, Brittany A.M. Devries, Elyssa M. Barrick, Shabnam Hossein, Daniel J. Cole, Chelsea V. Leonard, Evan C. Hahn, Andrew P. Teer, Grant S. Shields, George M. Slavich, Dost Ongur, J. Eric Jensen, Fei Du, Diego A. Pizzagalli, Michael T. Treadway

Psychological Science Faculty Publications and Presentations

Stress is a significant risk factor for the development of major depressive disorder (MDD), yet the underlying mechanisms remain unclear. Preclinically, adaptive and maladaptive stress-induced changes in glutamatergic function have been observed in the medial prefrontal cortex (mPFC). Here, we examine stress-induced changes in human mPFC glutamate using magnetic resonance spectroscopy (MRS) in two healthy control samples and a third sample of unmedicated participants with MDD who completed the Maastricht acute stress task, and one sample of healthy control participants who completed a no-stress control manipulation. In healthy controls, we find that the magnitude of mPFC glutamate response to the …

An Eeg Source-Space Analysis Of The Neural Correlates Underlying Self-Regulation, Stephanie M. Long

Graduate Theses and Dissertations

Self-regulation is the cognitive process of controlling our thoughts and behaviors to be aligned with our goals. This process is used in many different contexts and has been associated with contributions from several brain regions. This research aimed to investigate differences in four prefrontal areas of the brain while participants applied four different self-regulation strategies. We recorded EEG while participants (N = 132) performed three tasks which engaged each of the four self-regulation strategies: the AX-CPT task engaged proactive and reactive control, the Go/Nogo task engaged inhibitory control, and the hybrid Flanker Global/Local task engaged the resolution of response conflict. …

White-Matter Tract Connecting Anterior Insula To Nucleus Accumbens Predicts Greater Future Motivation In Adolescents, Josiah K. Leong, Tiffany C. Ho, Natalie L. Colich, Lucinda Sisk, Brian Knutson, Ian H. Gotlib

Psychological Science Faculty Publications and Presentations

The motivation to approach or avoid incentives can change during adolescence. Advances in neuroimaging allow researchers to characterize specific brain circuits that underlie these developmental changes. Whereas activity in the nucleus accumbens (NAcc) can predict approach toward incentive gain, activity in anterior insula (AIns) is associated with avoidance of incentive loss. Recent research characterized the structural white-matter tract connecting the two brain regions, but the tract has neither been characterized in adolescence nor linked to functional activity during incentive anticipation. In this study, we collected diffusion MRI and characterized the tract connecting the AIns to the NAcc for the first …

Optimal Control Of Excitable Systems Near Criticality, Kathleen Finlinson, Woodrow L. Shew, Danile B. Larremore, Juan G. Restrepo

Physics Faculty Publications and Presentations

Experiments suggest that the cerebral cortex gains several functional advantages by operating in a dynamical regime near the critical point of a phase transition. However, a long-standing criticism of this hypothesis is that critical dynamics are rather noisy, which might be detrimental to aspects of brain function that require precision. If the cortex does operate near criticality, how might it mitigate the noisy fluctuations? One possibility is that other parts of the brain may act to control the fluctuations and reduce cortical noise. To better understand basic aspects of controlling neural activity fluctuations, here we numerically and analytically study a …

Tuning Network Dynamics From Criticality To An Asynchronous State, Jingwen Li, Woodrow L. Shew

Physics Faculty Publications and Presentations

According to many experimental observations, neurons in cerebral cortex tend to operate in an asynchronous regime, firing independently of each other. In contrast, many other experimental observations reveal cortical population firing dynamics that are relatively coordinated and occasionally synchronous. These discrepant observations have naturally led to competing hypotheses. A commonly hypothesized explanation of asynchronous firing is that excitatory and inhibitory synaptic inputs are precisely correlated, nearly canceling each other, sometimes referred to as ‘balanced’ excitation and inhibition. On the other hand, the ‘criticality’ hypothesis posits an explanation of the more coordinated state that also requires a certain balance of excitatory …

Investigation Of The Role Of Heparin-Binding Pocket In Amyloid Fibrils Formation Of Fgf-1, I Gusti Ayu Agung Septiari

Graduate Theses and Dissertations

Human acidic fibroblast growth factor (aFGF/hFGF-1) is one of the promising molecules to be investigated to generate an in-depth understanding of the pathological mechanism of Alzheimer's disease (AD) neurodegenerative disorder characterized by the presence of amyloid fibrils. Some in vivo and human brain tissue studies proved the correlation of high-level expression of FGF-1-induced neuroinflammation and the occurrence of AD. The presence of amyloid fibrils as a hallmark of AD can be related to the generic property of the proteins to form amyloid fibrils; High level of FGF-1, in this case, may contribute to the formation of amyloid fibrils. As a …

Expression Analysis Of Cnidarian-Specific Neuropeptides In A Sea Anemone Unveils An Apical-Organ-Associated Nerve Net That Disintegrates At Metamorphosis, Hannah Zang, Nagayasu Nakanishi

Biological Sciences Faculty Publications and Presentations

Neuropeptides are ancient neuronal signaling molecules that have diversified across Cnidaria (e.g., jellyfish, corals, and sea anemones) and its sister group Bilateria (e.g., vertebrates, insects, and worms). Over the course of neuropeptide evolution emerged lineage-specific neuropeptides, but their roles in the evolution and diversification of nervous system function remain enigmatic. As a step toward filling in this knowledge gap, we investigated the expression pattern of a cnidarian-specific neuropeptide—RPamide—during the development of the starlet sea anemone Nematostella vectensis, using in situ hybridization and immunohistochemistry. We show that RPamide precursor transcripts first occur during gastrulation in scattered epithelial cells of the …

The Feedback-Related Negativity Is A Time-Dependent Brain Mechanism That Facilitates Aversive Learning: Implications For The Reinforcement Learning Frn Hypothesis, Eric Rawls

Graduate Theses and Dissertations

Organisms encode rewarding and aversive experiences through reinforcement learning, capitalizing on prediction errors (PEs), which adapt action strategies over time. Computational theories are explicit that PE signals should update action weights continuously over the course of a behavioral task, an important time-dependent variation that is eschewed in traditional neuroscience studies that average over large numbers of trials. I examined variation in reaction times and feedback-locked cortical activity over time as a function of PE to critically examine theories indicating that PE signals drive time-dependent learning. We recorded EEG while participants completed a novel reinforcement task that varied prediction error on …

The Functional And Structural Analysis Of Drosophila Robo2 In Axon Guidance, Lafreda Janae Howard

Graduate Theses and Dissertations

In animals with complex nervous systems such as mammals and insects, signaling pathways are responsible for guiding axons to their appropriate synaptic targets. Importantly, when this process is not successful during the development of an organism, outcomes include catastrophes such as human neurological diseases and disorders. It is vital to determine the underlying causes of such diseases by understanding the development of the nervous system. There are many pathways that have been identified to play a role in this, however, we lack an understanding of how these pathways can promote such diverse outcomes in different populations of neurons. These pathways …

Impact Of Excitation-Inhibition Balance/Imbalance On Dynamics Of Cortical Neural Networks, Vidit Agrawal

Graduate Theses and Dissertations

The purpose of this research is to study the implications of Excitation/Inhibition balance and imbalance on the dynamics of ongoing (spontaneous) neural activity in the cerebral cortex region of the brain.

The first research work addresses the question that why among the continuum of Excitation-Inhibition balance configurations, particular configuration should be favored? We calculate the entropy of neural network dynamics by studying an analytically tractable network of binary neurons. Our main result from this work is that the entropy maximizes at regime which is neither excitation-dominant nor inhibition-dominant but at the boundary of both. Along this boundary we see there …

The Functional Conservation Of Frazzled In Insects, Benjamin Wadsworth

Graduate Theses and Dissertations

Axons in the developing embryo receive and react to signals that direct their growth to reach target tissues at specified locations. The signal pathways that direct midline crossing of axons during embryonic development have been comprehensively examined in the past years using the Drosophila ventral nerve cord or the spinal cord as a model system. A number of these signaling mechanisms are conserved, however disparities have been found between species in general strategy or the molecular signals controlling the response of axons to guidance cues.

The Netrin-Frazzled pathway has been shown to aid in midline crossing of axons in the …

Electrophysiological Correlates Of Visual Object Category Formation In A Prototype-Distortion Task, Stephanie Marie Long

Graduate Theses and Dissertations

In perceptual learning studies, participants engage in extensive training in the discrimination of visual stimuli in order to modulate perceptual performance. Much of the literature in perceptual learning has looked at the induction of the reorganization of low-level representations in V1. However, much remains to be understood about the mechanisms behind how the adult brain (an expert in visual object categorization) extracts high-level visual objects from the environment and categorically represents them in the cortical visual hierarchy. Here, I used event-related potentials (ERPs) to investigate the neural mechanisms involved in object representation formation during a hybrid visual search and prototype …

Feedforward And Feedback Signals In The Olfactory System, Srimoy Chakraborty

Graduate Theses and Dissertations

The conglomeration of myriad activities in neural systems often results in prominent oscillations. The primary goal of the research presented in this thesis was to study effects of sensory stimulus on the olfactory system of rats, focusing on the olfactory bulb (OB) and the anterior piriform cortex (aPC). Extracellular electrophysiological measurements revealed distinct frequency bands of oscillations in OB and aPC. However, how these oscillatory fluctuations help the animal to process sensory input is not clearly understood. Here we show high frequency oscillations in olfactory bulb carry feedforward signals to anterior piriform cortex whereas feedback from the aPC is predominantly …

A Hidden Markov Factor Analysis Framework For Seizure Detection In Epilepsy Patients, Mahboubeh Madadi

Graduate Theses and Dissertations

Approximately 1% of the world population suffers from epilepsy. Continuous long-term electroencephalographic (EEG) monitoring is the gold-standard for recording epileptic seizures and assisting in the diagnosis and treatment of patients with epilepsy. Detection of seizure from the recorded EEG is a laborious, time consuming and expensive task. In this study, we propose an automated seizure detection framework to assist electroencephalographers and physicians with identification of seizures in recorded EEG signals. In addition, an automated seizure detection algorithm can be used for treatment through automatic intervention during the seizure activity and on time triggering of the injection of a radiotracer to …

Validity And Reliability Of A 5-Minute Web-Camera Based Eye Tracking Test To Assess Visual Memory And Cognition, Emily Bates

Graduate Theses and Dissertations

There are approximately 5.7 million Americans currently living with Alzheimer’s Disease (AD). Early detection of cognitive impairment allows for earlier treatment, potentially slowing or halting cognitive decline. A 30-min web-camera eye tracking assessment (30-min VPC) has been validated as a tool to predict AD risk. However, a shorter version would allow for greater scalability and improve user experience. The purpose of this study was to: 1) determine the validity of the 5-minute web-camera based VPC test with the 30-min test, 2) determine the test-retest reliability of the 5-min test, 3) compare the 5-minute test scores of cognitively intact adults (18-39 …

A Phenomenological Study Of The Lived Experiences Of Counseling Students In A Co-Facilitated Experiential Group, Alexandra Meyers

Graduate Theses and Dissertations

Research in the fields of experiential learning, group psychotherapy, and neuroscience has supported the inclusion of the experiential group in counseling training programs due to the potential for positive impact on students’ personal and professional development (Badenoch & Cox, 2010; Denninger, 2010). Investigations exploring counseling students’ experiences of the experiential group have been primarily limited to quantitative studies, while in-depth qualitative inquiry has been minimal. Additionally, an extensive review of the literature has found there have been no qualitative studies examining experiential groups co-facilitated by a course instructor and a doctoral student. The purpose of this phenomenological study was to …