Systems Neuroscience Commons^™

Anatomical Analysis Of Olfactory Sensory Neuron Regeneration Via Glomerular Synaptic Activity Markers In Adult Mice, William Wamack

Undergraduate Honors Theses

The olfactory system is a great model for studying regeneration due to the olfactory epithelium’s regenerative capability which makes it a potential a source of neural stem cells. The olfactory epithelium presents three types of cells: sustentacular cells which provide support and act as glial supporting cells; olfactory sensory neurons that are in charge of detecting odorant molecules in the air; and the stem cells that generated the aforementioned cell types. Olfactory sensory neurons are constantly dying and being replaced by new neurons originating from the stem cells that lie at the base of the olfactory epithelium. We have used …

The Effects Of False Heartbeat Feedback On Moral Judgment, Scott Koenig

Dissertations, Theses, and Capstone Projects

Research on human morality is at a crossroads, with one side claiming that moral judgment is the result of rational inference and the other side claiming that it is the result of emotion-laden intuition. This study investigated whether emotion drives moral judgment by manipulating a core component of the experience of emotion: physiological arousal. The sample consisted of 77 undergraduate students at Brooklyn College (57% women, 43% men; mean age = 20.1). One group of participants was led to believe their heart was beating quickly, and another group slowly, while they read and evaluated a series of text vignettes depicting …

Aberrant Age-Related Alterations In Spontaneous Cortical Activity In Participants With Cerebral Palsy, Hannah Bergwell

Theses & Dissertations

Cerebral Palsy (CP) is the most common neurodevelopmental motor disability, resulting in life-long sensory, perception and motor impairments. These impairments appear to drastically worsen with advancing age within the CP population, although the underlying neuro-physiological mechanisms remain poorly understood. Herein, we began to address this knowledge gap by utilizing magnetoencephalographic (MEG) to study how aging impacts the amplitude of spontaneous brain activity (i.e., resting state) in a cohort of 38 individuals with spastic diplegic CP (Age = 22.08 ± 10.46 years) and 67 neurotypical controls (NT) (Age = 19.56 ± 10.25 years). Participants completed an eyes-closed resting-state paradigm while undergoing …

The Functional Role Of Anatomical Feedback Connections In Visual Attention, Samantha Debes

Dissertations and Theses (Open Access)

Entrenched in a dense, highly connected network, cortical neurons receive heterogeneous inputs from diverse connections, including local feedforward and feedback signals. Over the years, neuroscientists have focused on feedforward and local connections, amassing a wealth of information on the purpose of these signals. However, the functional role of feedback connections remains a mystery, despite their sheer abundance and prevalence when compared to feedforward connections. The field has long hypothesized that feedback acts as a conduit for attentional signals, carrying them throughout the brain. Previous work on this topic has been variable. Though cognitively demanding neural processes, like attention, have traditionally …

Validation Of The 40 Hz Auditory Steady State Response As A Pharmacodynamic Biomarker Of Evoked Neural Synchrony, Muhammad Ummear Raza

Electronic Theses and Dissertations

Schizophrenia is a troubling and severe mental illness that is only incompletely treated by currently available drugs. New drug development is hindered by a scarcity of functionally relevant pharmacodynamic biomarkers that are translatable across preclinical and human subjects. Although psychosis is a major feature of schizophrenia, cognitive and negative symptoms determine the long-term functional outcomes for patients. Stimulus-evoked neural synchrony at gamma (~ 40 Hz) frequency plays an important role in the processing and integration of sensory information. Not surprisingly, schizophrenia patients show deficits in gamma oscillations. NMDA receptor (NMDAR) activation on fast-spiking parvalbumin-positive interneurons is deemed important for the …

Spatial Representation In Postrhinal Cortex, Patrick Lachance

Dartmouth College Ph.D Dissertations

Animals rely on a variety of internal and external cues to orient themselves when navigating their environments and determining their current spatial context. Information regarding these cues enters the brain from the navigator’s first-person perspective. Information of this type is considered to be egocentric, or self-centered. However, decades of behavioral, electrophysiological, and imaging research suggest that the brain contains a rich collection of spatial representations that are unrestricted by the animal’s first-person perspective, and instead are defined relative to the surrounding environment. These representations are considered allocentric, or world-centered. Despite an abundance of promising modeling work, the specific mechanisms by …

Probability Distributions Of Active Sensing, Kathleen Hoffman

Biology and Medicine Through Mathematics Conference

No abstract provided.

Characterization Of Local And Global Statistics In Three Kinds Of Medical Images, And An Example Of Their Role In A Clinical Judgment, Jonathan Victor, Amanda Simon, Craig K. Abbey

MODVIS Workshop

No abstract provided.

A Two-Layer Model Explains Higher-Order Feature Selectivity Of V2 Neurons, Timothy D. Oleskiw, Justin D. Lieber, J. Anthony Movshon, Eero P. Simoncelli

MODVIS Workshop

Neurons in cortical area V2 respond selectively to higher-order visual features, such as the quasi-periodic structure of natural texture. However, a functional account of how V2 neurons build selectivity for complex natural image features from their inputs – V1 neurons locally tuned for orientation and spatial frequency – remains elusive.

We made single-unit recordings in area V2 in two fixating rhesus macaques. We presented stimuli composed of multiple superimposed grating patches that localize contrast energy in space, orientation, and scale. V2 activity is modeled via a two-layer linear-nonlinear network, optimized to use a sparse combination of V1-like outputs to account …

Linking Spinal Cord Circuits With Upper Limb Sensorimotor Control In Adults With Cerebral Palsy, Saihari Dukkipati

Theses & Dissertations

Cerebral palsy (CP) is the most common neurological disorder originating in childhood, but most of the people living with CP are currently adults. While people with CP continue to get older, the amount of research focused on adults has been rather limited. The early childhood insults leading to CP are thought to originate in the brain, but the effects on the entire neuromuscular system across the lifespan have only recently started to be explored. Of note, recent neuroimaging evidence suggests that the cervical spinal cord structure is atypical in adults with CP. However, it is largely unclear how the neurophysiological …

Impact Of Brain State On Visual And Prefrontal Population Coding In Behaving Animals, Russell Milton

Dissertations and Theses (Open Access)

Patterns of neural activity in the brain constantly shift between different processing states. Earlier studies have established that the ongoing, spontaneous activity has major repercussions regarding how the brain processes incoming sensory stimuli. However, the interaction between behavioral activity and brain states throughout the cortical hierarchy of primates has not been understood. In particular, technical considerations have greatly limited the range of physical activities in which primate neuronal activity can be recorded. We have implemented two separate strategies to overcome these limitations. First, we have advanced wireless electrophysiological methodologies that enable recording high-yield neuronal data from animals as they freely …

Application Of Confocal Microscopy To Study The Neural Mechanisms Underlying Insect And Rodent Behavior, Christian Michelle Harris

Theses, Dissertations and Capstones

Posture and walking require support of the body weight, which is thought to be detected by sensory receptors in the legs. Specificity in sensory encoding occurs through the morphological properties of the sense organs (numerical distribution, receptor size) and their physiological response characteristics. These studies focus upon campaniform sensilla, receptors that detect forces as strains in the insect exoskeleton. To study the morphology of campaniform sensilla, the sites of mechanotransduction (cuticular caps) were imaged by light and confocal microscopy in four species (stick insects, cockroaches, blow flies and Drosophila). These data indicate that the gradient (range) of cap sizes may …

Does Bisphenol-A, An Estrogen-Like Environmental Toxin, Disrupt Expression Of The Neuronal Chloride Exporter Protein During Early Brain Development?, Mayra S. Mendez

Cal Poly Humboldt theses and projects

Bisphenol A (BPA), a manufactured compound found in consumer products, is known to adversely affect early brain development by disrupting normal estrogen signaling. Recently, BPA was reported to suppress expression of a gene encoding the neuron-specific chloride ion transporter, KCC2. Human and animal studies show suppressing KCC2 can cause neuronal and behavioral hyperactivity. Therefore, some adverse effects of BPA may be due to KCC2 suppression and consequent neuronal hyperactivity. This study aimed to determine whether BPA exposure during brain development alters KCC2 expression. A secondary purpose was to evaluate whether a new transgenic zebrafish line, KCC2:mCitrine,could be used to track …

Theta Burst Brain Stimulation In Painful Diabetic Neuropathy Patients: Investigating Neural Mechanisms, Bhushan Thakkar

Theses and Dissertations

Chronic pain (CP) is a significant contributor to disability and disease burden globally. In 2019, approximately 50.2 million adults (20.4% of the US population) experienced chronic pain, contributing to $560-635 billion in direct medical costs. In addition, the worldwide prevalence of diabetes mellitus has reached epidemic proportions and is set to increase to 629 million by 2045. Almost 50% of patients with diabetes present with diabetic neuropathy (DN), and one in five patients with diabetes presents with painful DN (pDN) which is the most common cause of neuropathic pain (NP) in the US. Symptomatic treatment is the mainstay of management …

Neural Processing Of Semantic Content In Movies, Maximilian Nentwich

Dissertations and Theses

Naturalistic stimuli, such as movies, contain interacting, multimodal and semantic features and allow for free exploration through eye movements. The full extent of neural responses to features such as motion, film cuts and eye movement behavior has not been established. The main hypothesis of this thesis is that complex multimodal and semantic stimuli in naturalistic movies engage a widespread ensemble of locations across the entire brain. To address this question I analyzed simultaneous intracranial and eyetracking data from over 6,000 electrodes across 23 patients with intractable epilepsy. Responses to fast eye movements – saccades – and film cuts are widespread …

Energy As A Limiting Factor In Neuronal Seizure Control: A Mathematical Model, Sophia E. Epstein

CMC Senior Theses

The majority of seizures are self-limiting. Within a few minutes, the observed neuronal synchrony and deviant dynamics of a tonic-clonic or generalized seizure often terminate. However, a small epilesia partialis continua can occur for years. The mechanisms that regulate subcortical activity of neuronal firing and seizure control are poorly understood. Published studies, however, through PET scans, ketogenic treatments, and in vivo mouse experiments, observe hypermetabolism followed by metabolic suppression. These observations indicate that energy can play a key role in mediating seizure dynamics. In this research, I seek to explore this hypothesis and propose a mathematical framework to model how …