Cognitive Neuroscience Commons^™

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 Neurological Asymmetry Of Self-Face Recognition, Aleksandra Janowska, Brianna Balugas, Matthew Pardillo, Victoria Mistretta, Katherine Chavarria, Janet Brenya, Taylor Shelansky, Vanessa Martinez, Kitty Pagano, Nathira Ahmad, Samantha Zorns, Abigail Straus, Sarah Sierra, Julian Keenan

Department of Biology Faculty Scholarship and Creative Works

While the desire to uncover the neural correlates of consciousness has taken numerous directions, self-face recognition has been a constant in attempts to isolate aspects of self-awareness. The neuroimaging revolution of the 1990s brought about systematic attempts to isolate the underlying neural basis of self-face recognition. These studies, including some of the first fMRI (functional magnetic resonance imaging) examinations, revealed a right-hemisphere bias for self-face recognition in a diverse set of regions including the insula, the dorsal frontal lobe, the temporal parietal junction, and the medial temporal cortex. In this systematic review, we provide confirmation of these data (which are …

Where To Draw The Line: Evaluating Visuospatial And Attentional Processing In Individuals With Autism Spectrum Disorders, Alisha Steigerwald

University Honors Theses

Objective: We investigated visuospatial processing in individuals with autism using bisection and quadrisection tasks to evaluate the presence of a possible downward vertical spatial bias that could provide insights into the preference for attending to the mouth in ASD populations.

Methods: Twenty participants with ASD and 20 age, IQ, and sex-matched control participants were recruited (ages 6-23). Participants were asked to bisect, quadrisect from the top, and quadrisect from the bottom vertical lines placed in their left, center, and right visual spaces. Distance from the true midpoint and quadripoint were calculated and compared between the two groups.

Results: No significant …

The Effect Of Diazepam On Early Neural Stem Cells Proliferative Activity And Hippocampal-Dependent Memory After Traumatic Brain Injury, Van Khanh Doan

University Honors Theses

Traumatic brain injury (TBI) induces an upregulation of neurogenesis in the brain specifically in the hippocampus, an area pertaining to learning and memory formation. Although this upregulated response is intuitively thought to be restorative, previous studies show that the nascent neurons generated after TBI exhibit abnormalities, such as aberrant morphologies and early migrations, which could suggest to be maladaptive. The GABA-A agonist diazepam has been shown to inhibit this upregulation in neurogenesis and normalizes dendrites after TBI. To determine whether this modulation of neurogenesis is ultimately beneficial or detrimental to cognitive recovery, diazepam was administered to C57BI/6J wild-type mice following …

Severe Covid-19 In Alzheimer’S Disease: Apoe4’S Fault Again?, Nian Xiong, Martin R. Schiller, Jingwen Li, Xiaowu Chen, Zhicheng Lin

Life Sciences Faculty Research

Challenges have been recognized in healthcare of patients with Alzheimer’s disease (AD) in the COVID-19 pandemic, given a high infection and mortality rate of COVID-19 in these patients. This situation urges the identification of underlying risks and preferably biomarkers for evidence-based, more effective healthcare. Towards this goal, current literature review and network analysis synthesize available information on the AD-related gene APOE into four lines of mechanistic evidence. At a cellular level, the risk isoform APOE4 confers high infectivity by the underlying coronavirus SARS-CoV-2; at a genetic level, APOE4 is associated with severe COVID-19; at a pathway level, networking connects APOE …

Effects Of Working Memory Load On Ensemble Versus Individual Object Processing, Clark Moore

Dissertations, Theses, and Capstone Projects

Ensemble perception is the ability of the visual system to summarize object groups by their statistical properties. At a fundamental level, past studies show clearly that ensembles are perceived, and statistical information is sent to working memory such that a subject may report on the averages (Ariely, 2001; Brady and Alvarez, 2011). Studies show that subjects are capable of reporting ensemble statistics for large groups of objects with high accuracy, inferring that this process bypasses the capacity limitations of attention and working memory (Chong and Treisman, 2003; Baijal et al., 2013; Huang, 2015; Epstein and Emmanouil, 2017, 2021). However, few …

The Effect Of Anticipatory Anxiety On Fear Extinction Learning, Daniela C. Echeverria

Dissertations, Theses, and Capstone Projects

Adaptive regulation of fear is dependent on successful fear extinction learning; therefore, investigating factors that both enhance and diminish fear extinction learning is a critical line of research. In the present study, we induce mild anticipatory anxiety during fear extinction learning in an attempt to modulate how participants extinguish fear memory. In the experiment, we apply a classic three-day fear learning protocol to both control participants (N = 20) and an experimental group (N = 20) with fear acquisition, fear extinction, and fear recovery phases; each phase is separated by a period of 24 hours and we use a skin …

Functional Connectivity Changes In The Default Mode Network In Moderate-To-Severe Traumatic Brain Injury, Emily J. Haight

Dissertations, Theses, and Capstone Projects

Traumatic brain injury (TBI) patients are known to have altered functional connectivity (FC), which has cognitive and behavioral significance and bears clinical implications. Previous literature has discovered a hyperconnectivity response to TBI, most notably in the default mode network (DMN). However, the exact pattern of changes in resting FC during the first year of recovery is unknown. We used resting-state functional magnetic resonance imaging to investigate longitudinal connectivity patterns in the DMN of 28 moderate-to-severe TBI patients as compared to 33 demographically matched healthy controls (HC). FC was assessed at 3, 6, and 12 months post-injury for patients using the …

Learning To Feel Safe: A Translational Study Of The Influence Of Safety Learning On Anxiety-Related Overgeneralized Fear, Hyein Cho

Dissertations, Theses, and Capstone Projects

Anxiety disorders are among the most common mental health diagnoses, affecting about a third of the population in their lifetime. However, approximately a third of individuals with anxiety do not respond to current treatment approaches, highlighting the need to identify additional potential therapeutic mechanisms. Safety learning is one such mechanism, but methodological challenges and a dearth of research have prevented the field from advancing the understanding of the role of safety learning in the etiology and remediation of anxiety disorders. Animal research, using single-cued safety learning paradigms, has yielded promising early findings, demonstrating that safety learning directly reduces anxiety-related behaviors …

Using Fnirs To Identify Brain Regions Involved In Emotional Face Processing In Infants At High Risk For Autism Spectrum Disorder, Christian Martinez

Dissertations, Theses, and Capstone Projects

Faces provide an abundance of salient information, and within a few hours of being born, infants already show preferential attention to faces and face-like stimuli. Autism spectrum disorder (ASD) is a developmental disorder consisting of social communication and interaction difficulties, and individuals with ASD show differences in the behavioral and neural processing of faces. Prospective studies with infants at high risk for ASD (HRA; by virtue of an older sibling with ASD) have begun to look at whether responses to faces could be an early marker of later ASD. Using functional near-infrared spectroscopy (fNIRS), the current study measured oxygenated hemoglobin …

Examining The Transient Neural Dynamics Underlying Working Memory Maintenance For Complex Visual Stimuli, Chelsea Reichert Plaska

Dissertations, Theses, and Capstone Projects

Working memory (WM) is the temporary storage of information to accomplish a future goal. The WM delay period is the time after encoding but before retrieval when information is being maintained, typically in the absence of relevant stimuli. Understanding how the brain supports maintenance during the delay period, and how neural activity and connectivity are related to memory is critical for advancing both basic knowledge as well as informing declines in memory and cognition related to neurodegenerative diseases and healthy aging. An open question in the field of WM research is how information is stored during this delay period. One …

Scaling Up Information Sharing On Hiv-Associated Neurocognitive Disorder: Raising Awareness And Knowledge Among Key Stakeholders, Renato M. Liboro, Paul A. Shuper, Lori E. Ross

Psychology Faculty Research

Although the majority of specialists and researchers in the field of HIV/AIDS are aware and knowledgeable about HIV-associated neurocognitive disorder (HAND) as a condition that affects as much as 50% of people living with HIV/AIDS (PLWH), research has documented that many health care and service providers who work directly with PLWH are either unaware of HAND or believe they do not know enough information about HAND to effectively support their clients experiencing neurocognitive challenges. Based on the findings of a qualitative study that interviewed 33 health care and service providers in HIV/AIDS services to identify and examine their awareness and …

Exploring Tactile Art-Making With Deafblind Students And Their Families: An Opportunity For Creative Play, Alice Rodgers

Expressive Therapies Capstone Theses

The impact of a deafblind diagnosis on an individual’s mental health and the well-being of the family involved can be profound. However, current research and available literature for the mental health treatment and therapy practices of deafblind persons and their families is limited (Kyzar et al., 2016; “WFDB Global Report 2018,” n.d.). This thesis used the Leeds Family Psychology and Therapy Service principles (Leeds FPTS) and the Expressive Therapies Continuum with established deafblind teaching strategies to facilitate an original arts-based community project entitled: “Things We Like.” This project provided an opportunity for deafblind students (ages three to 22) and their …

Monolingual And Bilingual Language Networks In Healthy Subjects Using Functional Mri And Graph Theory, Qiongge Li, Luca Pasquini, Gino Del Ferraro, Madeleine Gene, Kyung K. Peck, Hernán A. Makse, Andrei I. Holodny

Publications and Research

Bilingualism requires control of multiple language systems, and may lead to architectural differences in language networks obtained from clinical fMRI tasks. Emerging connectivity metrics such as k-core may capture these differences, highlighting crucial network components based on resiliency. We investigated the influence of bilingualism on clinical fMRI language tasks and characterized bilingual networks using connectivity metrics to provide a patient care benchmark. Sixteen right-handed subjects (mean age 42-years; nine males) without neurological history were included: eight native English-speaking monolinguals and eight native Spanish-speaking (L1) bilinguals with acquired English (L2). All subjects underwent fMRI with gold-standard clinical language tasks. Starting from …

Value-Generating Exploratory Trials In Neurodegenerative Dementias, Lauren G. Friedman, Nicholas Mckeehan, Yuko Hara, Jeffrey L. Cummings, Dawn C. Matthews, Jian Zhu, Richard C. Mohs, Deli Wang, Suzanne B. Hendrix, Melanie Quintana, Lon S. Schneider, Michael Grundman, Samuel P. Dickson, Howard H. Feldman, Judith Jaeger, Elizabeth C. Finger, J. Michael Ryan, Debra Niehoff, Susan L.J. Dickinson, Jessica T. Markowitz, Meriel Owen, Alessio Travaglia, Howard M. Fillit

School of Medicine Faculty Research

Drug development for Alzheimer disease and other neurodegenerative dementias, including frontotemporal dementia, has experienced a long history of phase 2 and phase 3 clinical trials that failed to show efficacy of investigational drugs. Despite differences in clinical and behavioral characteristics, these disorders have shared pathologies and face common challenges in designing early-phase trials that are predictive of late-stage success. Here, we discuss exploratory clinical trials in neurodegenerative dementias. These are generally phase 1b or phase 2a trials that are designed to assess pharmacologic effects and rely on biomarker outcomes, with shorter treatment durations and fewer patients than traditional phase 2 …

Mental Imagery In The Regulation Of Differential Fear Conditioning: A Multimodal Investigation Involving Self-Report, Psychophysiology, And Brain Imaging, Tyler Daniel Robinson

LSU Doctoral Dissertations

Mental imagery is a common component in a range of emotion regulation techniques. However, the effectiveness and neural mechanisms of regulation via mental imagery are underexplored due to a lack of studies targeting mental imagery specifically. This discrepancy results in uncertainty regarding the mechanism of regulation in existing paradigms. Biased competition for attentional resources presents a plausible model by which a mental imagery-based distracter can downregulate response to an emotional stimulus. If visualizing an imagined distracter effectively regulates emotional response, the inclusion of mental imagery components in other techniques represents a potential confound. To address this discrepancy, this dissertation investigates …

Aducanumab Produced A Clinically Meaningful Benefit In Association With Amyloid Lowering, Jeffrey Cummings, Paul Aisen, Cynthia Lemere, Alireza Atri, Marwan Sabbagh, Stephen Salloway

School of Medicine Faculty Research

No abstract provided.

Neurocognitive Impairment In People Living With Human Immunodeficiency Virus (Hiv): Risk Factors And Mortality, Zaeema Naveed

Theses & Dissertations

Despite the widespread use of combination antiretroviral therapy (cART), HIV-associated neurocognitive impairment (NCI) persists in people living with HIV (PLWH) with clinical and public health implications. Studies have generated inconsistent results regarding etiological factors for NCI in PLWH and a brief user-friendly predictive tool is desirable in clinical practice to assess the probability of having NCI in PLWH. Furthermore, factors associated with clinically meaningful decline in neurocognitive status and survival disadvantage for patients with NCI are understudied in the post-cART era. The goal of this dissertation was to investigate factors associated with baseline NCI and neurocognitive decline and the association …

Diagnostic Criteria For Apathy In Neurocognitive Disorders, David S. Miller, Philippe Robert, Larry Ereshefsky, Lawrence Adler, Daniel Bateman, Jeff Cummings, Steven T. Dekosky, Corinne E. Fischer, Masud Husain, Zahinoor Ismail, Judith Jaeger, Alan J. Lerner, Abby Li, Constantine G. Lyketsos, Valeria Manera, Jacobo Mintzer, Hans J. Moebius, Moyra Mortby, Didier Meulien, Stephane Pollentier, Anton Porsteinsson, Jill Rasmussen, Paul B. Rosenberg, Myuri T. Ruthirakuhan, Mary Sano, Carla Zucchero Sarracini, Krista L. Lanctôt

School of Medicine Faculty Research

Introduction: Apathy is common in neurocognitive disorders (NCD) but NCD-specific diagnostic criteria are needed. Methods: The International Society for CNS Clinical Trials Methodology Apathy Work Group convened an expert group and sought input from academia, health-care, industry, and regulatory bodies. A modified Delphi methodology was followed, and included an extensive literature review, two surveys, and two meetings at international conferences, culminating in a consensus meeting in 2019. Results: The final criteria reached consensus with more than 80% agreement on all parts and included: limited to people with NCD; symptoms persistent or frequently recurrent over at least 4 weeks, a change …

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 …