Sense Organs Commons^™

Best Screening: Introducing The Neonatal Assessment Visual European Grid To Nicus In Tennessee, Gabrielle Sledge

OTD Capstone Projects

Blind Early Services Tennessee (BEST) is an early intervention agency that serves children ages 0-5 with visual impairments across Tennessee. BEST serves over 200 children and families across the state offering early intervention (BEST Start), parent empowerment (BEST Advocate), and family support (BEST Together) programming. The purpose of this project was to assist in the implementation of an early identification initiative (BEST Screening) using the Neonatal Assessment Visual European Grid (NAVEG). The NAVEG is a newborn vision screening shown to identify neurological risk for visual impairments. The long-term goal of this program is to promote the screening and early identification …

Sex Differences In Hippocampal O-Glcnacylation Of The Adult Mouse Brain, Makenzie Johnson

Selected Honors Theses

The hippocampus is a structure in the brain crucial for learning and memory. This occurs by synaptic remodeling known as long term potentiation and long term depression. Modifications of proteins in the hippocampus can affect its function. One of these modifications is the addition of O-linked β-N-acetylglucosamine, also known as O-GlcNAc. This is a sugar produced from glucose by the hexosamine biosynthetic pathway that is reversibly added onto serine and threonine residues of proteins by O-GlcNAc Transferase, or OGT. It is reversibly removed from these residues by O-GlcNAcAse, or OGA. This modification has been implicated in diabetes, cardiac dysfunction, and …

A Proposed Method To Verify Physician Visual Estimation Of Intraoperative Corneal Edema From Refractive Measurement Images During Cataract Surgery, Karalee Corley

CMC Senior Theses

A patient’s resultant vision quality in a restorative Femtosecond Laser Assisted Cataract Surgery (FLACS) can be fine tuned via an intraoperative measurement of refractive power and axis of astigmatism in the aphakic state. Standard preoperative measurements often disagree with intraoperative measurements (Optiwave Refractive Analysis; Alcon, Inc.) on account of the inclusion or exclusion of posterior corneal curvature, leaving the ultimate lens selection to physician discretion. One additional suggested cause of disagreement is swelling at the corneal incision site (Corley and Carmack 2020).The following proposes a method to verify visual estimation of intraoperative corneal swelling from 2D gray-scale images collected during …

Role Of Meibum And Tear Phospholipids In The Evaporative Water Loss Associated With Dry Eye., Samiyyah M. Sledge

Electronic Theses and Dissertations

It is generally believed that the tear film lipid surface film inhibits the rate of evaporation (Revap) of the underlying tear aqueous. It is also generally believed that changes in the composition of the tear film lipid layer is responsible for an increase in Revap in patients with dry eye. Both of these ideas have never been proven. The purpose of the current studies was to test these ideas. Revap was measured in vitro gravimetrically. Lipid spreading was measured using Raman spectroscopy and microscopy. The influence of the following surface films on the Revap of the sub phase of physiologically …

Determining Age-Related Visual Memory And Line Length Perception In Children And Adults, Katie Exline

Undergraduate Honors Thesis Projects

There is little research in the field of visual memory and perceptual abilities of children as compared to adults. This thesis seeks to understand and provide new perspectives to this field with potential implications in the fields of optometry and education. Through two basic experiments, this thesis evaluates the abilities of individuals to perceive a visual stimulus and compare it other visual stimuli, while also observing their abilities to learn and remember various visual stimuli. Through experimentation using line length as the visual stimulus, the method of constant stimuli (MCS) evaluates subjects’ visual perception and the method of single stimuli …

The Effect Of Hypoxia On Brain Cell Proliferation In Weakly Electric Fish, Petrocephalus Degeni, Kaitlin Klovdahl

Senior Theses and Projects

Oxygen levels tend to remain at a steady state concentration in the Earth’s atmosphere, yet in some bodies of water, they can fluctuate and decrease drastically. Many organisms that inhabit the swamps, lakes, streams, and parts of the ocean where this occurs have evolved adaptations to manage this environmental uncertainty and continue normal oxygen consumption. The Lwamunda swamp in Uganda is chronically hypoxic, yet it is home to many species, including the electric fish Petrocephalus degeni. P. degeni are unusual by nature of their immense brain, and the Lwamunda swamp appears ill-suited for maintaining this large, metabolically active organ. To …

Melanopsin-Expressing Retinal Ganglion Cells In Control Vs. Glaucomatous Retinas, Edward Hamad

Williams Honors College, Honors Research Projects

Glaucoma is a common cause of vision loss worldwide and has a large scope of symptoms, ranging from pupillary reflex defects to sleep disorders. These issues can be explained partially by a recently found subtype of retinal ganglion cells that express melanopsin, denoted melanopsin-expressing retinal ganglion cells or mRGCs for short. These cells function primarily as photoreceptors in the non-image forming pathway, but can receive input from rods and cones. Since mRGCs play a role in the pupillary reflex and regulation of the sleep-wake cycle, I investigated if glaucoma leads to the degeneration of these cells in a mouse model …

Photoreception And Eye Regeneration Mechanisms In Planarians, Taylor R. Birkholz

Dissertations

Although humans lack the ability to regenerate complete organs and limbs following amputation or injury, there are many other species (both vertebrates and invertebrates) that can. Significant advances have been made in understanding the genetic mechanisms that regulate organ regeneration in these species, including regeneration of eye tissues such as the lens and retina. Planarians are an established historical model used to study regeneration due to their ability to regenerate any organ, including the eye. With recent advances in molecular genetic analyses, planarians are now an emerging model for the specific study of eye regeneration mechanisms. Furthermore, regeneration of the …

Water Transport In The Lateral Line Canal Of The Intertidal Fish Xiphister Mucosus (Girard 1858) And Its Significance To Evaporative Water With Preliminary Observations Of The Metabolic Consequences Of Water Loss, Whitney Anne Gayer

Dissertations and Theses

The lateral line canal system is a sensory organ found in all teleost fish that has a wide range of morphological variation. Variation in morphology may often be the result of evolutionary necessity where the need for function dictates form. Xiphister mucosus is an amphibious Stichaeid fish that inhabits the rocky intertidal zone of the northeastern Pacific Ocean. The rocky intertidal is considered an extreme environment where crashing waves and ebbing tides may require the specialization of adaptations for surviving the many abiotic stressors encountered there.

The lateral line trunk canal of Xiphister is regarded as unique among teleosts with …

Distortion In Body Schema: The Influence Of Body Fat And Mass On Perceptions Of Personal Size, Katarina Ann Ferrucci

Senior Projects Spring 2017

Obesity has been linked with a myriad of negative outcomes for both physical and mental health including feeding and eating disorders and cognitive impairments that affect perception of body size. Understanding the cognitive mechanisms and physiological factors that contribute to perception of body size may help us to comprehend how obesity impacts the construction and development of one’s mental body representations. Previous research by Scarpina, Castelnuovo, and Molinari (2014) suggests that, compared to those with a normal Body Mass Index, individuals with a BMI greater than 30 (obese) not only inaccurately estimate tactile and mental distances on their own bodies, …

Comparison Of Electrogustometrically Determined Taste Threshold And Phenylthiocarbamide Sensitivity Between Non-Diabetic Subjects With First Degree Relatives With Type 2 Diabetes And Non-Diabetic Subjects Without Type 2 Diabetic First Degree Relatives, Matthew E. Joseph Do

PCOM Biomedical Studies Student Scholarship

Diabetes is a systemic degenerative disease, having adverse effects on many different organ systems. Nerve conduction specifically related to taste is one of the affected functions and can lead to altered taste perceptions and taste thresholds. Electrogustometry was used in this study to evaluate taste thresholds, and taste sensitivity was tested using phenylthiocarbamide-impregnated testing strips. Healthy non-diabetic subjects were divided into two experimental groups: One with a first degree relative with Type 2 diabetes and the other matched controls having no family history of Type 2 diabetes. The hypotheses: 1). There is a significant difference in taste threshold values and …

A Light And Electron Microscopic Study Of Visual Neurons In The Medulla Externa Of The Crab Hemigrapsus Nudus, Yu Cheng Liao

Loma Linda University Electronic Theses, Dissertations & Projects

The decapod crustacean with a relatively well-defined visual system have contributed significantly to our understanding of visual neuron morphology and physiology. The general morphology of the optic lobes of several decapods were initially described by Parker (1897) and Hanstrom (1924). In the past few years, several light and electron microscope studies have been made on the lamina ganglionaris: the first optic ganglion, of the lobster (Hamori and Horridge, 1966a); the crayfish (Hafner, 1974; Nassel, 1976a), and the crab (Stowe et al., 1977; Rafuse et al., in preparation). As yet, no adequate description has been made of the visual neurons in …