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Vision Science

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Full-Text Articles in Biomedical Engineering and Bioengineering

On The Pursuit Of Developer Happiness: Webcam-Based Eye Tracking And Affect Recognition In The Ide, Tamsin Rogers Jan 2023

On The Pursuit Of Developer Happiness: Webcam-Based Eye Tracking And Affect Recognition In The Ide, Tamsin Rogers

Honors Theses

Recent research highlights the viability of webcam-based eye tracking as a low-cost alternative to dedicated remote eye trackers. Simultaneously, research shows the importance of understanding emotions of software developers, where it was found that emotions have significant effects on productivity, code quality, and team dynamics. In this paper, we present our work towards an integrated eye-tracking and affect recognition tool for use during software development. This combined approach could enhance our understanding of software development by combining information about the code developers are looking at, along with the emotions they experience. The presented tool utilizes an unmodified webcam to capture …


Neonatal Intraocular Injection And Delivery System, Nina Treacher, Cory Ramsey, Marie Kosco, Jackson Carrell Jan 2023

Neonatal Intraocular Injection And Delivery System, Nina Treacher, Cory Ramsey, Marie Kosco, Jackson Carrell

Williams Honors College, Honors Research Projects

The proposed project is a way to deliver liquid medicine into the neonatal eye to prevent retinal detachment with lower risk for bacterial infection and drug misplacement. Currently, ophthalmologists use diabetic needles to introduce medication to the neonate eye. They estimate the injection location with hand-held calipers. This may allow the medicine to be misplaced from poor needle placement and introduce preventable error. The goal is to improve the delivery system ophthalmologists currently use by investigating ways to alter or enhance commonly used injection systems to make the procedure safer and more effective.


The Interconnection Of The Vestibular And Oculomotor Systems Analyzed In Healthy Young Adults By Examining Postural Sway, Cassandra Martin May 2022

The Interconnection Of The Vestibular And Oculomotor Systems Analyzed In Healthy Young Adults By Examining Postural Sway, Cassandra Martin

Theses

In order to study the human brain in a non-invasive way, the vestibular and oculomotor systems have been analyzed simultaneously. To achieve this, an eye movement and balance assessment was conducted for 29 (23 male; 21.6 ± 3.8 years) healthy participants with no history of concussions, brain injuries, vertigo, migraines, brain surgeries, eye surgeries, or amblyopia. The tasks consisted of eyes open, eyes closed, horizontal saccades, vertical saccades, vergence jumps, horizontal vestibulo-ocular reflex (VOR), and vertical VOR. Each task was completed in two stances: feet shoulder width apart and feet together. Distance, velocity, sway area, center of pressure (COP) frequency, …


Investigating The Effect Of Dissolved Oxygen-Assisted Corneal Cross-Linking (Cxl) On Porcine Corneas, Julianni Dar May 2022

Investigating The Effect Of Dissolved Oxygen-Assisted Corneal Cross-Linking (Cxl) On Porcine Corneas, Julianni Dar

Electronic Theses and Dissertations

Corneal cross-linking is a clinical procedure that is known to stop the progression of keratoconus, an eye disease that affects the cornea’s structure, ultimately leading to vision loss in its advanced stages. The typical treatment plan includes riboflavin and UV-A exposure in the hope to increase the mechanical properties of the cornea. There are two types of CXL pathways, with Type-II CXL requiring oxygen. Naturally, the dissolved oxygen is limited in the cornea; therefore, limiting the effect of Type-II CXL. This study proposes to improve the Type-II CXL contribution by integrating dissolved oxygen during the standard CXL treatment used in …


Visuomotor Adaptation During Asymmetric Walking, Charles Napoli Oct 2021

Visuomotor Adaptation During Asymmetric Walking, Charles Napoli

Masters Theses

Necessary for effective ambulation, head stability affords optimal conditions for the perception of visual information during dynamic tasks. This maintenance of head-in-space equilibrium is achieved, in part, by the attenuation of the high frequency impact shock resulting from ground contact. While a great deal of experimentation has been done on the matter during steady state locomotion, little is known about how head stability or dynamic visual acuity is maintained during asymmetric walking.

In this study, fifteen participants were instructed to walk on a split-belt treadmill for ten minutes while verbally reporting the orientation of a randomized Landolt-C optotype that was …


Laparoscopic Image Recovery And Stereo Matching, Wenyao Xia Mar 2021

Laparoscopic Image Recovery And Stereo Matching, Wenyao Xia

Electronic Thesis and Dissertation Repository

Laparoscopic imaging can play a significant role in the minimally invasive surgical procedure. However, laparoscopic images often suffer from insufficient and irregular light sources, specular highlight surfaces, and a lack of depth information. These problems can negatively influence the surgeons during surgery, and lead to erroneous visual tracking and potential surgical risks. Thus, developing effective image-processing algorithms for laparoscopic vision recovery and stereo matching is of significant importance. Most related algorithms are effective on nature images, but less effective on laparoscopic images.

The first purpose of this thesis is to restore low-light laparoscopic vision, where an effective image enhancement method …


When The Brain Plays A Game: Neural Responses To Visual Dynamics During Naturalistic Visual Tasks, Jason Ki Jan 2021

When The Brain Plays A Game: Neural Responses To Visual Dynamics During Naturalistic Visual Tasks, Jason Ki

Dissertations and Theses

Many day-to-day tasks involve processing of complex visual information in a continuous stream. While much of our knowledge on visual processing has been established from reductionist approaches in lab-controlled settings, very little is known about the processing of complex dynamic stimuli experienced in everyday scenarios. Traditional investigations employ event-related paradigms that involve presentation of simple stimuli at select locations in visual space and discrete moments in time. In contrast, visual stimuli in real-life are highly dynamic, spatially-heterogeneous, and semantically rich. Moreover, traditional experiments impose unnatural task constraints (e.g., inhibited saccades), thus, it is unclear whether theories developed under the reductionist …


Development Of Light Actuated Chemical Delivery Platform On A 2-D Array Of Micropore Structure, Hojjat Rostami Azmand, Hojjat Rostami Azmand Jan 2021

Development Of Light Actuated Chemical Delivery Platform On A 2-D Array Of Micropore Structure, Hojjat Rostami Azmand, Hojjat Rostami Azmand

Dissertations and Theses

Localized chemical delivery plays an essential role in the fundamental information transfers within biological systems. Thus, the ability to mimic the natural chemical signal modulation would provide significant contributions to understand the functional signaling pathway of biological cells and develop new prosthetic devices for neurological disorders. In this paper, we demonstrate a light-controlled hydrogel platform that can be used for localized chemical delivery in a high spatial resolution. By utilizing the photothermal behavior of graphene-hydrogel composites confined within micron-sized fluidic channels, patterned light illumination creates the parallel and independent actuation of chemical release in a group of fluidic ports. The …


Implementation Of A Computer-Vision System As A Supportive Diagnostic Tool For Parkinson’S Disease, Diego Machado Reyes May 2020

Implementation Of A Computer-Vision System As A Supportive Diagnostic Tool For Parkinson’S Disease, Diego Machado Reyes

Honors Theses

Parkinson’s disease is the second most common neurodegenerative disorder, affecting nearly 1 million people in the US and it is predicted that the number will keep increasing. Parkinson’s disease is difficult to diagnose due to its similarity with other diseases that share the parkinsonian symptoms and the subjectivity of its assessment, thus increasing the probabilities of misdiagnosis. Therefore, it is relevant to develop diagnostic tools that are quantitatively based and monitoring tools to improve the patient’s quality of life. Computer-based assessment systems have shown to be successful in this field through diverse approaches that can be classified into two main …


A Comparison Of Neural Activity For Peripersonal And Extrapersonal Viewing In Real And Virtual Environments, Olivia Eustice May 2020

A Comparison Of Neural Activity For Peripersonal And Extrapersonal Viewing In Real And Virtual Environments, Olivia Eustice

Honors Theses

This study involved a series of tests comparing the similarities and differences in neural activity at a subject’s peripheral and extrapersonal space in the real environment and virtual reality. We hypothesized that there would be similar brain activity at each of these environments depending on the focal distance of an object from the participant. Peripheral space is the visual space that is a reachable distance from a person. It has an overall neural pattern in the dorsal stream of the brain. Extrapersonal space is the visual space that does not directly surround a person and cannot be directly acted on. …


Noncontact Multiscale Diffuse Optical Imaging Of Deep Tissue Hemodynamics In Animals And Humans, Siavash Mazdeyasna Jan 2020

Noncontact Multiscale Diffuse Optical Imaging Of Deep Tissue Hemodynamics In Animals And Humans, Siavash Mazdeyasna

Theses and Dissertations--Biomedical Engineering

Blood flow (BF) impacts the delivery of oxygen and nutrients to tissues and the removal of metabolic byproducts from tissues. Imaging of BF distributions helps characterize many diseases associated with tissue hypoxia/ischemia. The purpose of this study was to develop and validate a novel, noninvasive, noncontact, high-density camera-based speckle contrast diffuse correlation tomography (scDCT) device for use in both animal and human studies. The scDCT uses a galvo-mirror to remotely deliver the focused point near-infrared light to source positions and a sensitive 2D camera to quantify spatial diffuse speckle fluctuations, resulting from the movement of red blood cells in deep …


Vector Flow Imaging In Pediatric Cardiology - Extracting And Validating Data, Mason Belue May 2019

Vector Flow Imaging In Pediatric Cardiology - Extracting And Validating Data, Mason Belue

Biomedical Engineering Undergraduate Honors Theses

In the field of bedside cardiac diagnostic imaging, Doppler Ultrasound (DU) is the gold standard for diagnosing heart conditions. The largest benefit of DU is its ability to noninvasively image cardiac flow and allow the estimation of blood velocity and quantification of anatomical disease. However, to get correct velocity estimation, the position of the transducer in relation to the flow field needs to be known. This is the problem of angle/direction dependency and limits DUs accuracy when imaging in areas where perfect alignment or exact position of the transducer in relation to flow field is not possible or known, such …


A Microfluidic Tissue Array (Μfta) For Personalized Medicine Using Tumor Biopsies, A.H. R. Ahmed Jan 2019

A Microfluidic Tissue Array (Μfta) For Personalized Medicine Using Tumor Biopsies, A.H. R. Ahmed

Dissertations and Theses

Cancer is recognized as a complex disease with both genetic and epigenetic drivers that can vary from one individual to another. While very early research into cancer treated it as a clonal malfunction that could originate from as small as a single deregulated cell, the disease itself manifests itself with several more complexities beyond tumorigenic cells only. The tumor microenvironment itself – from the extracellular matrix to stromal cells - cooperate with tumor cells in a symbiotic manner towards metastatic progression. Clinical studies have provided more information regarding the degree of individualization possible, such that patients with similar genetic makeup …


Controlled Migration Of Retinal Progenitor Cells Within Electro-Chemotactic Fields, Shawn Mishra Jan 2019

Controlled Migration Of Retinal Progenitor Cells Within Electro-Chemotactic Fields, Shawn Mishra

Dissertations and Theses

Vision loss in retinal degenerative diseases is overwhelmingly attributed to damage and death of retinal photoreceptor cells. Studies in mouse retina have suggested that transplantation of isolated post-natal or stem cell-derived retinal progenitor cells (RPCs) to replace apoptotic or damaged photoreceptors may be a novel approach to restore vision. Thus far, outcomes project that the amount of restored visual response depends upon the migration of transplanted cells from insertion in the sub-retinal space to the outer nuclear layer (ONL). However, transplantation efficiency is exceedingly low – ~5% cells transplanted enter the retina – directly limiting the efficacy of the treatments. …


Development Of An Eye Movement Based Predictive Model For Discrimination Of Parkinson's Disease From Other Parkinsonisms And Controls, Mary Anisa Kannan Jan 2019

Development Of An Eye Movement Based Predictive Model For Discrimination Of Parkinson's Disease From Other Parkinsonisms And Controls, Mary Anisa Kannan

Theses and Dissertations

Purpose: Due to the neurological aspects of Parkinson’s Disease (PD) and the sensitivity of eye movements to neurological issues, eye tracking has the potential to be an objective biomarker with higher accuracy in diagnosis than current clinical standards. Currently when PD is diagnosed clinically, there is an accuracy of 74% when diagnosed by a general practitioner and 82% when diagnosed by a movement disorder specialist. This study was designed to: 1. Assess eye movements as a potential biomarker for Parkinson’s Disease. 2. Determine if eye movements can distinguish between Parkinson’s Disease and commonly confounded movement disorders with parkinsonian symptoms. 3. …


Collective Behavior Of Drosophila Melanogaster Neural Progenitor And Imaginal Disc Cells Within Controlled Microenvironments, Caroline D. Pena Jan 2019

Collective Behavior Of Drosophila Melanogaster Neural Progenitor And Imaginal Disc Cells Within Controlled Microenvironments, Caroline D. Pena

Dissertations and Theses

Regenerative therapies for the damaged visual system have introduced stem-derived cells to recapitulate developmental processes and initiate functional regeneration in different components of the eye. The developing visual system in Drosophila Melanogaster offers a model in which to analyze the associated processes in retinogenesis. The optic nerve is critical to vision and is developmentally preceded in Drosophila by a structure called the Optic Stalk (OS). Collective migration of neural and retinal progenitor cells (RPCs) from the developing brain lobes (DBL) to the Imaginal Disc (ID), through the OS, is a fundamental part of regenerative strategies in retina. Developmental signals governing …


Collective Chemotaxis Of Retinal Neural Cells From Drosophila Melanogaster In Controlled Microenvironments, Stephanie Zhang Jan 2018

Collective Chemotaxis Of Retinal Neural Cells From Drosophila Melanogaster In Controlled Microenvironments, Stephanie Zhang

Dissertations and Theses

More than 172 million people are influenced by a retinal disorder that stems from either age-related or developmental causes. Of those, 1.5 million people endure a developmental retinal disorder. In the developing retina, neural cells undergo a series of highly complicated differentiation and migration process. A main cause of these diseases is abnormal collective migration of neural progenitors hindering the retinogenesis process. However, our grasp of collective migration and signaling molecules, critical to the developing retina, is incompletely understood. Understanding the molecular mechanisms, such as the fibroblast growth factor pathway, that regulate glial and neuronal migration provides decisive insights in …


Eye Movement Control: An Index For Athleticism, Brittany L. Oshea Jan 2017

Eye Movement Control: An Index For Athleticism, Brittany L. Oshea

Theses and Dissertations

Athletic potential is one of the most complex human traits. An elite athlete is produced from a complex interaction of an innumerable number of traits exhibited by the athlete. However, it’s not clear whether these traits are innate, allowing the athlete to excel, or, alternatively, are a consequence of practice. To be successful, athletes rely heavily on sensory information from the visual and vestibular systems. This study investigated the relationship eye movement control has with innate athleticism by comparing the saccadic and Vestibulo-Ocular Reflex (VOR) responses of former, no longer practicing, elite athletes against their age and gender matched counterparts …


Sonar For The Visually Impaired, Anastasia Newark, Edwin Ng, Scott Terhorst Jun 2014

Sonar For The Visually Impaired, Anastasia Newark, Edwin Ng, Scott Terhorst

Biomedical Engineering

There are currently no inexpensive assistive devices that allow the visually impaired detect low hanging objects that are above waist height and may cause injury, such as a rope or tree branch. The challenge presented to the team by the Quality of Life Plus Lab (QL+) was to develop a Sonar Cane device that attaches to a traditional white cane to address this problem. This device must be lightweight, inexpensive to manufacture, have a long battery life, and accurately detect obstacles to prevent user injury.


Image Fusion And Axial Labeling Of The Spine, Brandon Miles Jan 2014

Image Fusion And Axial Labeling Of The Spine, Brandon Miles

Electronic Thesis and Dissertation Repository

In order to improve radiological diagnosis of back pain and spine disease, two new algorithms have been developed to aid the 75% of Canadians who will suffer from back pain in a given year. With the associated medical imaging required for many of these patients, there is a potential for improvement in both patient care and healthcare economics by increasing the accuracy and efficiency of spine diagnosis. A real-time spine image fusion system and an automatic vertebra/disc labeling system have been developed to address this. Both magnetic resonance (MR) images and computed tomography (CT) images are often acquired for patients. …


An Investigation Of Markov Random Fields For Bayesian Reconstruction Of Single Photon Emission Computed Tomography, Lloyd Fredrick Arrowood Aug 2013

An Investigation Of Markov Random Fields For Bayesian Reconstruction Of Single Photon Emission Computed Tomography, Lloyd Fredrick Arrowood

Doctoral Dissertations

This research investigates the use of Markov random fields for Bayesian reconstruction algorithms to be used with high-resolution and high-sensitivity SPECT systems for small animal imaging. It extends previous research on mechanical models for Bayesian image reconstruction by using a three-dimensional nonconforming finite element model and linear elasticity concepts to derive minimum potential energy functionals which regularize the reconstruction process. It combines dual collimator SPECT projection data by using high-resolution data to penalize lower-resolution data. It compares the new three-dimensional penalized reconstruction technique with existing penalized techniques through the use of modulation transfer and contrast discrimination functions.


Real-Time Prostate Motion Tracking For Robot-Assisted Laparoscopic Radical Prostatectomy, Mehdi Esteghamatian May 2012

Real-Time Prostate Motion Tracking For Robot-Assisted Laparoscopic Radical Prostatectomy, Mehdi Esteghamatian

Electronic Thesis and Dissertation Repository

Radical prostatectomy surgery (RP) is the gold standard for treatment of localized prostate cancer (PCa). Recently, emergence of minimally invasive techniques such as Laparoscopic Radical Prostatectomy (LRP) and Robot-Assisted Laparoscopic Radical Prostatectomy (RARP) has improved the outcomes for prostatectomy. However, it remains difficult for surgeons to make informed decisions regarding resection margins and nerve sparing since the location of the tumour within the organ is not usually visible in a laparoscopic view. While MRI enables visualization of the salient structures and cancer foci, its efficacy in LRP is reduced unless it is fused into a stereoscopic view such that homologous …


The Effect Of Practice On Eye Movements In The 1/D Paradigm, Will Seidelman Jan 2011

The Effect Of Practice On Eye Movements In The 1/D Paradigm, Will Seidelman

University of Kentucky Master's Theses

Previous studies have demonstrated that observers may ignore highly salient feature singletons during a conjunction search task through focusing the attentional window (Belopolsky, Zwaan, Theeuwes, & Kramer, 2007), or by the suppression of bottom-up information (Treisman & Sato, 1990). In the current study, observers’ eye movements were monitored while performing a search task in which a feature singleton was present and corresponded with the target at a chance level. With practice, observers were less likely to make an initial saccade toward the singleton item, but initial saccades directed at the target were likely throughout. Results demonstrate that, in an effort …


Effect Of Light Source On The Sorting Performance Of A Vision-Based Robot System, Johnny T. Li Jan 1996

Effect Of Light Source On The Sorting Performance Of A Vision-Based Robot System, Johnny T. Li

Dissertations and Theses @ UNI

Industries look toward computer vision as a means to automate materials handling. To make this choice more appealing, useful and feasible vision applications must be explored. However, illuminance variation in the factory environment can undermine the capability and applicability of vision-based control systems. The purposes of this study were (a) to design and develop a vision-based robot material sorting system, (b) to determine the optimal settings for this system under fluorescent and incandescent lighting for two different color parts on a moving conveyor, and (c) to determine the sorting performance of this system under each light source.

The main components …