Neuroscience and Neurobiology Commons^™

Task-Driven Influences On Fixational Eye Movements, Jonathan Victor, Yen-Chu Lin, Michele Rucci

MODVIS Workshop

There is now compelling evidence that the spatiotemporal remapping carried out by fixational eye movements (FEMs) is an essential step in visual processing. Moreover, the overall Brownian-like statistics of FEMs are calibrated to map fine spatial detail into the temporal frequency range to which retinal circuitry is tuned. Here, we tested the hypothesis that the detailed spatial characteristics of FEMs can be adjusted to task demands via cognitive influences that operate even in the absence of a visual stimulus. We examined FEMs in a task that required subjects (N=6) to report which of two letters was displayed. Trials were blocked; …

Active Encoding Of Space Through Time, Michele Rucci, Jonathan D. Victor

MODVIS Workshop

No abstract provided.

Extracting Edges In Space And Time During Visual Fixations, Lynn Schmittwilken, Marianne Maertens

MODVIS Workshop

No abstract provided.

Automated Delineation Of Visual Area Boundaries And Eccentricities By A Cnn Using Functional, Anatomical, And Diffusion-Weighted Mri Data, Noah C. Benson, Bogeng Song, Toshikazu Miyata, Hiromasa Takemura, Jonathan Winawer

MODVIS Workshop

Delineating visual field maps and iso-eccentricities from fMRI data is an important but time-consuming task for many neuroimaging studies on the human visual cortex because the traditional methods of doing so using retinotopic mapping experiments require substantial expertise as well as scanner, computer, and human time. Automated methods based on gray-matter anatomy or a combination of anatomy and functional mapping can reduce these requirements but are less accurate than experts. Convolutional Neural Networks (CNNs) are powerful tools for automated medical image segmentation. We hypothesize that CNNs can define visual area boundaries with high accuracy. We trained U-Net CNNs with ResNet18 …

Toward A Manifold Encoding Neural Responses, Luciano Dyballa, Andra M. Rudzite, Mahmood S. Hoseini, Mishek Thapa, Michael P. Stryker, Greg D. Field, Steven W. Zucker

MODVIS Workshop

Understanding circuit properties from physiological data presents two challenges: (i) recordings do not reveal connectivity, and (ii) stimuli only exercise circuits to a limited extent. We address these challenges for the mouse visual system with a novel neural manifold obtained using unsupervised algorithms. Each point in our manifold is a neuron; nearby neurons respond similarly in time to similar parts of a stimulus ensemble. This ensemble includes drifting gratings and flows, i.e., patterns resembling what a mouse would “see” running through fields.

Regarding (i), our manifold differs from the standard practice in computational neuroscience: embedding trials in neural coordinates. Topology …

Constraining The Binding Problem Using Maps, Zhixian Han, Anne Sereno

MODVIS Workshop

We constrained the binding problem by creating maps of different attributes. We compared the performance of different models with different maps in our current study. Our preliminary results showed that the performance of the model is the highest when location maps were used. These results suggest that the optimal way to constrain the binding problem is to create location maps of different attributes.

From Image Gradients To A Perceptual Metric Space, Alan Johnston

MODVIS Workshop

How do we achieve a sense of spatial dimension from a sense of location? There are three predominant ideas about how we achieve this; spatial isomorphism, in which what we see reflects differences in distance or size in the brain; that spatial extent depends upon motor sensations or intentions related to eye movements; and that distance is computed from the degree of correlation in neural activity between adjacent locations, with distance inversely proportional to the correlation. There are problems with each of these approaches, for example, neural correlation may depend more on image structure than adjacency - consider the case …

V1 Saliency Hypothesis And Central-Peripheral Dichotomy (Cpd), Li Zhaoping Prof. Dr.

MODVIS Workshop

No abstract provided.

A Dynamical Model Of Binding In Visual Cortex During Incremental Grouping And Search, Daniel Schmid, Daniel A. Braun, Heiko Neumann

MODVIS Workshop

Binding of visual information is crucial for several perceptual tasks. To incrementally group an object, elements in a space-feature neighborhood need to be bound together starting from an attended location (Roelfsema, TICS, 2005). To perform visual search, candidate locations and cued features must be evaluated conjunctively to retrieve a target (Treisman&Gormican, Psychol Rev, 1988). Despite different requirements on binding, both tasks are solved by the same neural substrate. In a model of perceptual decision-making, we give a mechanistic explanation for how this can be achieved. The architecture consists of a visual cortex module and a higher-order thalamic module. While the …

Efficient Coding Of Local 2d Shape, James Elder, Timothy D. Oleskiw, Ingo Fruend, Gerick M. Lee, Andrew Sutter, Anitha Pasupathy, Eero Simoncelli, J Anthony Movshon, Lynne Kiorpes, Najib Majaj

MODVIS Workshop

Efficient coding provides a concise account of key early visual properties, but can it explain higher-level visual function such as shape perception? If curvature is a key primitive of local shape representation, efficient shape coding predicts that sensitivity of visual neurons should be determined by naturally-occurring curvature statistics, which follow a scale-invariant power-law distribution. To assess visual sensitivity to these power-law statistics, we developed a novel family of synthetic maximum-entropy shape stimuli that progressively match the local curvature statistics of natural shapes, but lack global structure. We find that humans can reliably identify natural shapes based on 4^th and …

Preparing Non-Human Primates To Study Hand-Eye Coordination In Frontal Eye Fields (Fef) During Delayed Movement Task, Juliusz Cydzik

McKelvey School of Engineering Graduate Student Theses & Dissertations

ABSTRACT OF THE THESIS Preparing Non-Human Primates to Study Hand-Eye Coordination in Frontal Eye Fields (FEF) During Delayed Movement Task by Juliusz Cydzik Master of Science in Biomedical Engineering Washington University in St. Louis, 2023 Professor Lawrence Snyder, Chair Hand-eye coordination enables humans and non-human primates to use their hands and eyes to perform various tasks. We are interested in coordination at the systems level, where saccades and reaches are encoded. The parietal reach region (PRR), situated at the posterior end of the intraparietal sulcus (IPS) and overlapping portions of the medial intraparietal area (MIP) and V6a, is commonly attributed …

Manage Your Money Wisely: How Consumers And Marketers Can Effectively Communicate Money Issues, Alexander Park

Olin Business School Graduate Student Theses and Dissertations

Consumers and marketers find it challenging to communicate money matters. For example, consumers experience discomfort and uneasiness when discussing financial issues with their social relationships. Firms often receive backlash when sharing their good financial deeds (e.g., charitable efforts) with consumers. Because financial matters can be a sensitive topic, in my research, I explore the difficulties consumers and marketers experience when communicating money issues and how they can better navigate these problems.In Chapter One, I investigate a particularly uneasy interaction that consumers often face with their friends and acquaintances: the need to ask for money back. Seven fully preregistered studies (N …

Sleep Duration Is Associated With Caudate Volume And Executive Function, Nicole Jones

Honors Theses

The ineligible role of the caudate nucleus in sleep has been implicated throughout multiple scientific studies. Previous literature has shown that greater caudate volume is associated with longer habitual sleep duration in older adults- ranging from 55 years of age and up. However, the association between sleep duration and caudate volume remains unknown in the younger population. In this study, we examined the caudate volume in youth to older adults (10 to 85 years old) with a greater sample size (N=464) to increase statistical power. The volumetric size of the caudate nucleus showed significantly positive association with habitual sleep duration, …

The Interhemispheric Auditory Tract Connectivity And Autism Spectrum Disorder, Josie Long

Honors Theses

Individuals with autism spectrum disorder (ASD) can have abnormal responses and hypersensitivity to sounds (Haesen et al., 2011). ASD is also related to inattentive, hyperactive, and impulsive behaviors (Bradley & Isaacs, 2006). One study by Stansberry et al. (2022) found that a higher fractional anisotropy (FA) of interhemispheric auditory white matter is associated with higher impulsivity. Our study examined the interhemispheric auditory tract (IAT) to determine whether it is impacted by ASD. We used diffusion tensor imaging (DTI) data from Autism Brain Imaging Data Exchange utilizing two datasets so that we could replicate primary findings. We first isolated the IAT …

Vi Energy-Efficient Memristor-Based Neuromorphic Computing Circuits And Systems For Radiation Detection Applications, Jorge Iván Canales Verdial

Electrical and Computer Engineering ETDs

Radionuclide spectroscopic sensor data is analyzed with minimal power consumption through the use of neuromorphic computing architectures. Memristor crossbars are harnessed as the computational substrate in this non-conventional computing platform and integrated with CMOS-based neurons to mimic the computational dynamics observed in the mammalian brain’s visual cortex. Functional prototypes using spiking sparse locally competitive approximations are presented. The architectures are evaluated for classification accuracy and energy efficiency. The proposed systems achieve a 90% true positive accuracy with a high-resolution detector and 86% with a low-resolution detector.

Eco-Interoception: What Plants, Fungi And Protista Have Taught My Body, Sara Riley Dotterer

Art Theses and Dissertations

To me, ecology is the relational, full-body awareness that I am made up of and deeply connected to everything around me; and for better or worse, this is reciprocal. I form ecotones, an ecological transitional zone between two ecosystems, with the world around me. I use this ecotonal lens to blur binaries and dissolve boundaries between me and the world “outside my body.” During my Masters of Fine Arts at Southern Methodist University, I have continuously explored and represented the lives of various more-than-human species outside of my body, including plants, fungi and protista through an ecotonal lens. Although these …

Neuroinflammatory And Metabolomic Temporal Dynamics From Inhaled Wildfire Smoke With Attenuation Via Pharmacological Intervention, David Scieszka

Biomedical Sciences ETDs

Wildfire smoke is a global issue affecting nearly all humans on the surface of this Earth. Smoke dispersion from wildfires can span continents and cross oceans with amazing ease. Furthermore, total acres of land burned per year in the United States has roughly doubled since 1980, meaning this issue will persist for an indeterminate amount of time. Exposure to wildfire smoke is hazardous and promotes aging-associated events in the cardiopulmonary systems. Yet long- and short-term effects on the brain remain relatively unknown. From these, it is critically important to understand the neurological impacts from wildfire smoke exposure; to compare these …

Local Field Potentials In The Male Rat Nucleus Accumbens During Effort-Based Behavior, Celine Aliko, John Salamone, Alev Ecevitoglu

Honors Scholar Theses

Major depression is a devastating disorder that consists of multiple symptoms such as low mood and motivational dysfunction. It has been shown that motivational dysfunction can be studied in animal models by using effort-based choice paradigms, which vary in their response requirements. It has been reported that dopamine depletion in the nucleus accumbens decreases ratio-scheduled lever-pressing in a manner related to the size of the ratio requirement. One dopamine depleting agent is tetrabenazine (TBZ), which has been shown to decrease lever-pressing and induce low-effort bias. The current study aims to investigate behavioral and electrophysiological changes that occur with animals performing …

Characterizing The Effects Of Light On The Early Onset Photoreceptor Function Loss In Mucolipidosis Type Iv, Rebecca Cistulli

Masters Theses, 2020-current

Retinal degenerative diseases (RDD’s) are a diverse group of retinal disorders that cause visual impairment. While RDD prevalence is high, little is known about the molecular mechanisms underlying the pathogenesis within some of these disorders. Here we are trying to elucidate the molecular mechanisms that drive early onset photoreceptor function loss in the RDD, Mucolipidosis type IV (MLIV). MLIV is a lysosomal storage disorder that results from loss of function mutations in the MCOLN1 gene and leads to a disruption of autophagy. The MCOLN1 gene encodes a lysosomal cation channel called Trpml1. Based on previous data from our lab, we …

All The Rage: Assessing The Age/Rage Signaling Pathway’S Effects On Healthspan And The Physiological Processes Of Aging, Brandon Ashmore

Honors Theses

Advanced glycation end products (AGEs) are protein, lipid, or nucleotide molecules that have been combined with sugars through nonenzymatic, irreversible glycation and oxidation reactions. Their accumulation in the body has been associated with the natural aging process and a wide range of pathologies, including chronic inflammation, sustained oxidative stress, diabetes, neurodegenerative diseases, atherosclerosis, and cancer. Their interaction with the receptor for advanced glycation end products (RAGE) has been linked to several proinflammatory signaling pathways associated with neurotoxicity and vascular lesions. While some research has been done on the possible health benefits of RAGE inhibition to extend lifespan, our study hopes …