Neuroscience and Neurobiology Commons^™

An Initial Analysis Of A Long-Term Ketogenic Diet’S Impact On Motor Behavior, Brain Purine Systems, And Nigral Dopamine Neurons In A New Genetic Rodent Model Of Parkinson’S Disease, Jacob Rubin, William H. Church

Senior Theses and Projects

A growing body of research suggests that dopaminergic cell death seen in Parkinson’s disease is caused by mitochondrial dysfunction. Oxidative stress, with subsequent generation of reactive oxygen species, is the hallmark biochemical product of mitochondrial dysfunction. The ketogenic diet has been found to enhance mitochondrial energy production, protect against reactive oxygen species-generated cell death, and increase adenosine, a purine that modulates dopamine activity. The current study evaluates the effects of a long-term (5-month) ketogenic diet on behavioral, neurochemical, and neuroanatomical measures in PINK1-KO rats, a new animal model of Parkinson’s disease. Both wild-type and PINK1-KO animals fed a ketogenic diet …

Superoxide Dismutase 1: Novel Insights On Disease Models And Tissue Specificity In Amyotrophic Lateral Sclerosis, Matthew James Crisp

Arts & Sciences Electronic Theses and Dissertations

Mutations in superoxide dismutase 1 (SOD1) are known to cause dominantly-inherited amyotrophic lateral sclerosis (ALS), a rapidly-fatal adult-onset neurodegenerative disorder defined by motor neuron loss and progressive paralysis. In the past twenty years, research into the disorder has been driven by the creation of numerous transgenic animal models that have yielded multiple theories on the pathogenesis of the disease. Patients and animal models with SOD1 mutations express the defective protein in every cell, yet the disease only affects tissues in the neuromuscular axis. In this dissertation, I present original work exploring two aspects of SOD1 ALS. The first details the …

The Molecular And Cellular Basis For Cold Sensation, Daniel Brenner

Arts & Sciences Electronic Theses and Dissertations

The ability to sense changes in temperature is crucial to surviving harsh environments. Over the last decade several ion channels that have been proposed to be cold sensitive have been identified, most notably TRPM8 and TRPA1. Although these molecules have been extensively studied in vitro, their exact roles in cold sensation in vivo are still debated. This uncertainty is in large part due to problems with the standard methods of testing cold sensitivity in vivo, which often rely on subjective measures of cold responsiveness. Experiments using these subjective measures have been repeated by different groups and have yielded conflicting results, …

The Murine Accessory Olfactory Bulb As A Model Chemosensory System: Experimental And Computational Analysis Of Chemosensory Representations, Gary Francis Hammen

Arts & Sciences Electronic Theses and Dissertations

A common challenge across sensory processing modalities is forming meaningful associations between the neural responses and the outside world. These neural representations of the world must then be integrated across different sensory systems contributing to each individuals perceptual experience. While there has been considerable study of sensory representations in the visual system of humans and multiple model organisms, other sensory domains, including olfaction, are less well understood. In this thesis, I set out to better understand the sensory representations of the mouse accessory olfactory system (AOS), a part of the olfactory system. The mouse AOS, our model chemosensory system, comprises …

Development And Investigation Of Sparse Co-Adaptive Algorithms In Ecog Based Closed-Loop Brain Computer Interface, Piyush Karande

McKelvey School of Engineering Theses & Dissertations

Electrocorticography (ECoG) has gained a lot of momentum and has become a serious contender as a recording modality for the implementation of Brain-Computer Interface (BCI) systems in the last few years. ECoG signals provide the right balance between minimal invasiveness and robust spectral information to accomplish a BCI task. However, all the BCI studies until now have used signals recorded from a large number of implanted electrodes and a larger number of spectral features. The recording and processing of these signals uses a lot of electrical power and thus hinders its use outside the research setting. To translate this research …

The Effects Of Lipopolysaccharide-Induced Neuroinflammation On Learning And Forgetting In Juvenile Rats, Michele Barry

Seton Hall University Dissertations and Theses (ETDs)

The inability to remember events experienced very early in life is referred to as Infantile Amnesia (IA) and has been observed in both humans and animals. Over the years interest in the phenomenon waned, but has recently increased with the discovery of new neurobiological methods to study brain function (e.g., Callaghan, Li & Richardson, 2014). The neurobiological mechanism behind IA has yet to be determined, but several innovative theories have been developed with these new research methods. The neurogenesis hypothesis theorizes that increased neurogenesis during early development disrupts previously established memories. The hippocampus, an area that mediates both the memory …

Virtual V1sion: A Collaborative Coding Project, Cheryl Olman

MODVIS Workshop

Virtual V1sion is a new idea for fostering modeling collaborations and data sharing. While still in its infancy, the ultimate goal is a website that hosts repositories for (1) interchangeable model elements, (2) datasets that can be fit/predicted by those models, and (3) educational modules that explain the background for both the models and the datasets. The scope of the modeling is limited to predictions of V1 responses, although not all computations represented by model elements in Virtual V1sion are required to be V1-intrinsic: a goal of the project is to provide a framework in which predictions for modulation by …

Parametrically Constrained Lightness Model Incorporating Edge Classification And Increment-Decrement Neural Response Asymmetries, Michael E. Rudd

MODVIS Workshop

Lightness matching data from disk-annulus experiments has the form of a parabolic (2^nd-order polynomial) function when matches are plotted against annulus luminance on log-log axes. Rudd (2010) has proposed a computational cortical model to account for this fact and has subsequently (Rudd, 2013, 2014, 2015) extended the model to explain data from other lightness paradigms, including staircase-Gelb and luminance gradient illusions (Galmonte, Soranzo, Rudd, & Agostini, 2015). Here, I re-analyze parametric lightness matching data from disk-annulus experiments by Rudd and Zemach (2007) and Rudd (2010) for the purpose of further testing the model and to try to constrain …

Failure Of Surface Color Cues Under Natural Changes In Lighting, David H. Foster, Iván Marín-Franch

MODVIS Workshop

Color allows us to effortlessly discriminate and identify surfaces and objects by their reflected light. Although the reflected spectrum changes with the illumination spectrum, cone photoreceptor signals can be transformed to give useful cues for surface color. But what happens when both the spectrum and the geometry of the illumination change, as with lighting from the sun and sky? Is it possible, as a matter of principle, to obtain reliable cues by processing cone signals alone? This question was addressed here by estimating the information provided by cone signals from time-lapse hyperspectral radiance images of five outdoor scenes under natural …

Diffuse Traumatic Brain Injury Induces Prolonged Immune Sysregulation And Potentiates Hyperalgesia Following A Peripheral Immune Challenge, Rachel K. Rowe, Gavin I. Ellis, Jordan L. Harrison, Adam D. Bachstetter, Gregory F. Corder, Linda J. Van Eldik, Bradley K. Taylor, Francesc Marti, Jonathan Lifshitz

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Background: Nociceptive and neuropathic pain occurs as part of the disease process after traumatic brain injury (TBI) in humans. Central and peripheral inflammation, a major secondary injury process initiated by the traumatic brain injury event, has been implicated in the potentiation of peripheral nociceptive pain. We hypothesized that the inflammatory response to diffuse traumatic brain injury potentiates persistent pain through prolonged immune dysregulation.

Results: To test this, adult, male C57BL/6 mice were subjected to midline fluid percussion brain injury or to sham procedure. One cohort of mice was analyzed for inflammation-related cytokine levels in cortical biopsies and serum along an …

Alterations In Gray Matter Volume Due To Unilateral Hearing Loss, Xingchao Wang, Pengfei Xu, Peng Li, Zhenmin Wang, Fu Zhao, Zhixian Gao, Lei Xu, Yue-Jia Luo, Jin Fan, Pinan Liu

Publications and Research

Although extensive research on neural plasticity resulting from hearing deprivation has been conducted, the direct influence of compromised audition on the auditory cortex and the potential impact of long durations of incomplete sensory stimulation on the adult cortex are still not fully understood. In this study, using voxel-based morphometry, we evaluated gray matter (GM) volume changes that may be associated with reduced hearing ability and the duration of hearing impairment in 42 unilateral hearing loss (UHL) patients with acoustic neuromas compared to 24 normal controls. We found significant GM volume increases in the somatosensory and motor systems and GM volume …

Working Memory Impairments In Chromosome 22q11.2 Deletion Syndrome: The Roles Of Anxiety And Stress Physiology, Ashley F. P. Sanders

University of New Orleans Theses and Dissertations

Stress and anxiety negatively impact the working memory system by competing for executive resources. Broad memory deficits have been reported in individuals with chromosome 22q11.2 deletion syndrome (22q11.2DS). We investigated anxiety and physiological stress reactivity in relation to visuospatial working memory impairments in 20 children with 22q11.2DS and 32 typically developing children (M = 11.10 years, SD = 2.95). Results indicate reduced post-stress RSA recovery and overall increased levels of cortisol in children with 22q11.2DS. Additionally, anxiety mediated the relationship between 22q11.2DS and visuospatial working memory impairment. However, there was no indication that stress response physiology mediated this association. …

Modeling The Joint Distribution Of Scene Events At An Edge, James Elder, Ying Li

MODVIS Workshop

Edges in an image arise from discontinuities in scene variables, namely reflectance (R), illumination (I), depth (D) and surface orientation (O). Prior studies on edge classification have viewed it as a binary classification problem: each edge is assumed to arise from one of two disjoint categories (e.g., depth or not depth, shadow or not shadow). Here we suggest an alternate view in which an edge may signal discontinuities in any combination of the scene variables (RIDO). To explore this model, we had 4 trained observers label one randomly selected edge in each of 1,000 randomly selected images drawn from the …

Identifying Falsifiable Predictions Of The Divisive Normalization Model Of V1 Neurons, Tadamasa Sawada, Alexander A. Petrov

MODVIS Workshop

The divisive normalization model (DNM, Heeger, 1992) accounts successfully for a wide range of phenomena observed in single-cell physiological recordings from neurons in primary visual cortex (V1). The DNM has adjustable parameters to accommodate the diversity of V1 neurons, and is quite flexible. At the same time, in order to be falsifiable, the model must be rigid enough to rule out some possible data patterns. In this study, we discuss whether the DNM predicts any physiological result of the V1 neurons based on mathematical analysis and computational simulations. We identified some falsifiable predictions of the DNM. The main idea is …

Modelling Response Properties Across The Orientation Map In Visual Cortex, Erin M. Koch, Jianzhong Jin, Jose-Manuel Alonso, Qasim Zaidi

MODVIS Workshop

Stimulus orientation in the primary visual cortex of primates and carnivores is mapped as iso-orientation domains radiating from pinwheel centers, where orientation preferences of neighboring cells change circularly. Whether this orientation map has a function is debated, because many mammals, such as rodents, do not have such maps. Here we model our physiological results that two fundamental properties of visual cortical responses, contrast saturation and cross-orientation suppression, are stronger within iso-orientation domains than at pinwheel centers. Our model expands on a standard thalamic model of cross orientation suppression, and explains differences between orientation domains by intra-cortical excitation (not normalization) from …

Derivatives And Inverse Of A Linear-Nonlinear Multi-Layer Spatial Vision Model, Borja Galan, Marina Martinez-Garcia, Praveen Cyriac, Thomas Batard, Marcelo Bertalmio, Jesus Malo

MODVIS Workshop

Analyzing the mathematical properties of perceptually meaningful linear-nonlinear transforms is interesting because this computation is at the core of many vision models. Here we make such analysis in detail using a specific model [Malo & Simoncelli, SPIE Human Vision Electr. Imag. 2015] which is illustrative because it consists of a cascade of standard linear-nonlinear modules. The interest of the analytic results and the numerical methods involved transcend the particular model because of the ubiquity of the linear-nonlinear structure.

Here we extend [Malo&Simoncelli 15] by considering 4 layers: (1) linear spectral integration and nonlinear brightness response, (2) definition of local contrast …

Towards A Functional Explanation Of The Connectivity Lgn - V1, Marina Martinez-Garcia, Borja Galan, Luis M. Martinez, Jesus Malo

MODVIS Workshop

The principles behind the connectivity between LGN and V1 are not well understood. Models have to explain two basic experimental trends: (i) the combination of thalamic responses is local and it gives rise to a variety of oriented Gabor-like receptive felds in V1 [1], and (ii) these filters are spatially organized in orientation maps [2]. Competing explanations of orientation maps use purely geometrical arguments such as optimal wiring or packing from LGN [3-5], but they make no explicit reference to visual function. On the other hand, explanations based on func- tional arguments such as maximum information transference (infomax) [6,7] usually …

Towards A Unified Model Of Classical And Extra-Classical Receptive Fields, David A. Mély, Thomas Serre

MODVIS Workshop

One of the major goals in neuroscience is to understand how the cortex processes information. A substantial effort has thus gone into mapping classical receptive fields (cRF) across areas of the visual cortex and characterizing input-output relationships through linear-nonlinear response functions. Recently, there has been a lot of interest in mapping the extra-classical receptive field (extra-cRF) as well, by using contextual stimuli. The extra-cRF is a region outside the cRF that modulates a cell’s response but that is incapable of driving it on its own. However, existing models typically focus on one particular visual modality (form, motion, disparity or color), …

Classifying Music Perception And Imagination Using Eeg, Avital Sternin

Electronic Thesis and Dissertation Repository

This study explored whether we could accurately classify perceived and imagined musical stimuli from EEG data. Successful EEG-based classification of what an individual is imagining could pave the way for novel communication techniques, such as brain-computer interfaces. We recorded EEG with a 64-channel BioSemi system while participants heard or imagined different musical stimuli. Using principal components analysis, we identified components common to both the perception and imagination conditions however, the time courses of the components did not allow for stimuli classification. We then applied deep learning techniques using a convolutional neural network. This technique enabled us to classify perception of …

How Deep Is The Feature Analysis Underlying Rapid Visual Categorization?, Sven Eberhardt, Jonah Cader, Thomas Serre

MODVIS Workshop

Rapid categorization paradigms have a long history in experimental psychology: Characterized by short presentation times and fast behavioral responses, these tasks highlight both the speed and ease with which our visual system processes natural object categories. Previous studies have shown that feed-forward hierarchical models of the visual cortex provide a good fit to human visual decisions. At the same time, recent work has demonstrated significant gains in object recognition accuracy with increasingly deep hierarchical architectures: From AlexNet to VGG to Microsoft CNTK – the field of computer vision has championed both depth and accuracy. But it is unclear how well …