Engineering Commons^™

2-Channel Eeg Neurofeedback System, Tim Erwin, Donna Nikjou, Sebastian Turkewitz

Electrical Engineering

This work describes the design of an EEG-based neurofeedback system which provides users with real-time feedback on their level of focus or relaxation. By analyzing the spectral content of the brain activity measured via scalp electrodes, focus and relaxation levels can be quantified. Based on these measurements, live feedback in the form of moving bar graphs is provided to users, allowing them to gain awareness of their mental-state and more efficiently learn how to consciously relax or focus. This project covers the design of the system, including amplification and filtering stages, digitization, and signal processing. The system interfaces with a …

Reciprocal Regulation Of Transketolase-Like 1 And Hypoxia-Inducible Factor 1 Alpha In Metabolic Reprogramming And Growth Of Diffuse Midline Glioma, H3 K27m-Mutant, Christopher Andrew Waker

Browse all Theses and Dissertations

Diffuse midline glioma, K27M-mutant (DMG) are intractable brain tumors, primarily occurring in the pediatric and adolescent population. Patients have a median survival of less than one year after diagnosis. A lack of therapeutic targets has been a barrier to improvement in patient survival. Irradiation therapy improves symptoms while chemotherapy and surgical intervention, for the most part, have not yet demonstrated utility for treatment. DMG are characterized by a histone H3 mutation that results in the genome-wide loss of epigenetic-repressive marks on K27 and is associated with the misexpression of genes, like Cancer/Testis antigens. A member of this group, transketolase-like 1 …

Peristaltic Flow In The Glymphatic System., Francesco Romanò, Vinod Suresh, Peter Galie, James B Grotberg

Henry M. Rowan College of Engineering Departmental Research

The flow inside the perivascular space (PVS) is modeled using a first-principles approach in order to investigate how the cerebrospinal fluid (CSF) enters the brain through a permeable layer of glial cells. Lubrication theory is employed to deal with the flow in the thin annular gap of the perivascular space between an impermeable artery and the brain tissue. The artery has an imposed peristaltic deformation and the deformable brain tissue is modeled by means of an elastic Hooke's law. The perivascular flow model is solved numerically, discovering that the peristaltic wave induces a steady streaming to/from the brain which strongly …

3d Architectural Analysis Of Neurons, Astrocytes, Vasculature & Nuclei In The Motor And Somatosensory Murine Cortical Columns, Jared Leichner

FIU Electronic Theses and Dissertations

Characterization of the complex cortical structure of the brain at a cellular level is a fundamental goal of neuroscience which can provide a better understanding of both normal function as well as disease state progression. Many challenges exist however when carrying out this form of analysis. Immunofluorescent staining is a key technique for revealing 3-dimensional structure, but subsequent fluorescence microscopy is limited by the quantity of simultaneous targets that can be labeled and intrinsic lateral and isotropic axial point-spread function (PSF) blurring during the imaging process in a spectral and depth-dependent manner. Even after successful staining, imaging and optical deconvolution, …

Development Of Photoacoustic Tomographic Systems For Brain Hemorrhage Detection, Karl Kratkiewicz

Wayne State University Dissertations

Preterm neonates (age) and/or with low birth weight (

Photoacoustic imaging (PAI) is an imaging modality which derives its contrast from differences in optical absorption coefficients of tissue through laser irradiation and acoustic detection. Therefore, PAI derives its signal directly from optical absorbers such as blood; the critical component in a hemorrhage. We discuss operation and processing methods of our Verasonics Vantage system. We then investigate thermal safety of PAI in mouse model for various laser pulse repetitions rates and illumination duration. We then develop two photoacoustic tomographic systems for eventual translation to clinic for hemorrhage detection. One system being …

The Brain's Large-Scale Electrophysiological Signals : Fundamental Attributes And Neurosurgical Applications, Mohammad Amin N/A Nourmohammadi

Legacy Theses & Dissertations (2009 - 2024)

Brain’s electrophysiological signals are most certainly the ultimate source for studying the sophisticated neural network inside our cranium. The unparalleled complexity of these biosignalsis the quintessential manifestation of their underlying complicated neurophysiological processes. Studying brain signals on the cellular level provides valuable information regarding the brain’s electrophysiology on the small-scale. However, it is the remarkable network in the large-scale that gives rise to the brain’s extraordinary attributes and exceptional capabilities—perception, cognition, computation, and consciousness are all the emergent byproducts of the dynamic neuronal interactions on the network level. In this sense, the large-scale electrophysiological signals, recorded from the surface of …

Post-Acquisition Processing Confounds In Brain Volumetric Quantification Of White Matter Hyperintensities, Ahmed A. Bahrani, Omar M. Al-Janabi, Erin L. Abner, Shoshana H. Bardach, Richard J. Kryscio, Donna M. Wilcock, Charles D. Smith, Gregory A. Jicha

Neurology Faculty Publications

BACKGROUND: Disparate research sites using identical or near-identical magnetic resonance imaging (MRI) acquisition techniques often produce results that demonstrate significant variability regarding volumetric quantification of white matter hyperintensities (WMH) in the aging population. The sources of such variability have not previously been fully explored.

NEW METHOD: 3D FLAIR sequences from a group of randomly selected aged subjects were analyzed to identify sources-of-variability in post-acquisition processing that can be problematic when comparing WMH volumetric data across disparate sites. The methods developed focused on standardizing post-acquisition protocol processing methods to develop a protocol with less than 0.5% inter-rater variance.

RESULTS: A series …

Distinct Patterns Of Default Mode And Executive Control Network Circuitry Contribute To Present And Future Executive Function In Older Adults, Christopher A. Brown, Frederick A. Schmitt, Charles D. Smith, Brian T. Gold

Neuroscience Faculty Publications

Executive function (EF) performance in older adults has been linked with functional and structural profiles within the executive control network (ECN) and default mode network (DMN), white matter hyperintensities (WMH) burden and levels of Alzheimer's disease (AD) pathology. Here, we simultaneously explored the unique contributions of these factors to baseline and longitudinal EF performance in older adults. Thirty-two cognitively normal (CN) older adults underwent neuropsychological testing at baseline and annually for three years. Neuroimaging and AD pathology measures were collected at baseline. Separate linear regression models were used to determine which of these variables predicted composite EF scores at baseline …

Role Of P-Glycoprotein In Alzheimer’S Disease For Enhanced Brain Elimination Of Amyloid-Β, Hope Holt

Theses and Dissertations

Alzheimer’s disease (AD), the most common form of neurodegenerative disorder, is characterized by deposition of amyloid-β (Aβ) plaques in the brain. Aβ monomer undergoes nucleation to form oligomers, then soluble aggregates, then fibrils which make up the plaques. Aβ oligomer species are believed to be the most neurotoxic aggregate species. Currently under investigation is a mechanism for Aβ removal from the brain, across the blood-brain barrier (BBB). P-glycoprotein (P-gp) is a membrane-bound efflux protein located on the apical, or blood, side of the BBB, which transports a wide variety of substrates. Further complicating this potential clearance mechanism is the reduction …

A Pilot Study Identifying Brain-Targeting Adaptive Immunity In Pediatric Extracorporeal Membrane Oxygenation Patients With Acquired Brain Injury, Sterling B. Ortega, Poornima Pandiyan, Jana Windsor, Vanessa O. Torres, Uma M. Selvaraj, Amy Lee, Michael Morriss, Fenghua Tian, Lakshmi Raman, Ann M. Stowe

Neurology Faculty Publications

OBJECTIVES: Extracorporeal membrane oxygenation provides short-term cardiopulmonary life support, but is associated with peripheral innate inflammation, disruptions in cerebral autoregulation, and acquired brain injury. We tested the hypothesis that extracorporeal membrane oxygenation also induces CNS-directed adaptive immune responses which may exacerbate extracorporeal membrane oxygenation-associated brain injury.

DESIGN: A single center prospective observational study.

SETTING: Pediatric and cardiac ICUs at a single tertiary care, academic center.

PATIENTS: Twenty pediatric extracorporeal membrane oxygenation patients (0-14 yr; 13 females, 7 males) and five nonextracorporeal membrane oxygenation Pediatric Logistic Organ Dysfunction score matched patients.

INTERVENTIONS: None.

MEASUREMENTS AND MAIN RESULTS: Venous blood samples were …

Modeling Eeg And Tdcs In Scirun Software Packages, Aiden Keene, Aiden Thomas Keene

Senior Honors Projects

Never before has there been a greater emphasis on improving the shortcomings of treating mental health conditions. Our generation has more knowledge about technological practices with the potential to monitor and treat mental health symptoms than that of any generation before us. A breakthrough in this field made by CREmedical is called Tripolar Concentric Ring Electrodes (TCRE’s), which can measure signals from the brain more accurately than conventional electrodes. At CREmedical, TCREs are being used to study differences in electrical activity in the brain so as to identify abnormalities, and monitor responses to stimulation therapies. This semester I had the …

Investigation Of The Ms2 Bacteriophage Capsid As An Mri-Capable, Brain-Targeted Nanoparticle Platform, Stephanie M. Curley

Legacy Theses & Dissertations (2009 - 2024)

Novel methods are needed to traverse the blood-brain barrier (BBB) and deliver drugs to specific targets in the brain. To this end, MS2 bacteriophage was explored as a multifunctional transport and targeting vector. The MS2 capsid exterior was modified with two different targeting moieties for delivery across the BBB and targeting specific regions of interest in the brain. Successful modification of MS2 capsids with a brain targeting peptide and NMDAR2D-targeting antibody was confirmed by immunoblotting and fluorescence detection. To measure transport efficiency of MS2 particles across an in vitro BBB model, a highly sensitive RT-qPCR protocol was developed and implemented. …

Brain Motion, Deformation, And Potential Injury During Soccer Heading, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Working Papers

This paper addresses the problem of what is happening physically inside the skull during head-ball contact. Mathematical models based upon Newton’s laws of motion and numerical methods are used to create animations of brain motion and deformation inside the skull.

Initially a 1 cm gap filled with cerebrospinal fluid (CSF) separates the brain from the rigid skull in adults and older children. Whole head acceleration induces a pulse of artificial gravity within the skull. Because brain density differs slightly from that of CSF, the brain accelerates and strikes the inner aspect of the skull, undergoing viscoelastic deformation, ranging from 1 …

Circle Of Willis Model For Transcranial Doppler Ultrasound Training, Conner J. Beyersdorf, Ben Hage, Greg Bashford

UCARE Research Products

Transcranial Doppler (TCD) ultrasound is a technique involving the use of high frequency transmitters to measure intracranial blood flow. The brain is supplied by blood in an arterial anastomosis called the Circle of Willis. Using TCD ultrasound on the circle is difficult and requires practice and teaching. A functional model of the Circle of Willis could prove to be a valuable teaching tool. Through the use of AutoCAD and 3D printing software, an anatomically accurate model was created and set in gelatin phantom inside of a plastic skull. Milk was pumped through the model with a peristaltic pump to simulate …

Spatio-Temporal Progression Of Cortical Activity Related To Continuous Overt And Covert Speech Production In A Reading Task, Jonathan S. Brumberg, Dean J. Krusienski, Shreya Chakrabarti, Aysegul Gunduz, Peter Brunner, Anthony L. Ritaccio, Gerwin Schalk

Electrical & Computer Engineering Faculty Publications

How the human brain plans, executes, and monitors continuous and fluent speech has remained largely elusive. For example, previous research has defined the cortical locations most important for different aspects of speech function, but has not yet yielded a definition of the temporal progression of involvement of those locations as speech progresses either overtly or covertly. In this paper, we uncovered the spatio-temporal evolution of neuronal population-level activity related to continuous overt speech, and identified those locations that shared activity characteristics across overt and covert speech. Specifically, we asked subjects to repeat continuous sentences aloud or silently while we recorded …

Computational Assessment Of Neural Probe And Brain Tissue Interface Under Transient Motion, Michael Polanco, Sebastian Bawab, Hangsoon Yoon

Mechanical & Aerospace Engineering Faculty Publications

The functional longevity of a neural probe is dependent upon its ability to minimize injury risk during the insertion and recording period in vivo, which could be related to motion-related strain between the probe and surrounding tissue. A series of finite element analyses was conducted to study the extent of the strain induced within the brain in an area around a neural probe. This study focuses on the transient behavior of neural probe and brain tissue interface with a viscoelastic model. Different stages of the interface from initial insertion of neural probe to full bonding of the probe by astro-glial …

Magnetic Resonance Imaging Of Cerebrovascular Reactivity Using Gas Inhalation Challenges, Harshan Ravi

Bioengineering Dissertations

Cerebrovascular reactivity (CVR) is a measure of dilation capacity of cerebral vasculature. It is an important biomarker for the vascular functionality and integrity, and may have clinical indications in stroke, atherosclerosis, Moyamoya disease, multiple sclerosis, brain tumor, and other neurological disorders. The most commonly used approach to measure CVR is by applying a physiological maneuver to alter the arterial carbon dioxide (CO2) concentration (e.g. inhaling a small amount of CO2 which is a potent vasodilator), while continuously acquiring BOLD MR images. However, the current method suffers from several limitations related to specificity, sensitivity, and physiological modeling of the measured signal. …

Multichannel Characterization Of Brain Activity In Neurological Impairments, Yalda Shahriari

Biomedical Engineering Theses & Dissertations

Hundreds of millions of people worldwide suffer from various neurological and psychiatric disorders. A better understanding of the underlying neurophysiology and mechanisms for these disorders can lead to improved diagnostic techniques and treatments. The objective of this dissertation is to create a novel characterization of multichannel EEG activity for selected neurological and psychiatric disorders based on available datasets. Specifically, this work provides spatial, spectral, and temporal characterizations of brain activity differences between patients/animal models and healthy controls, with focus on modern techniques that quantify cortical connectivity, which is widely believed to be abnormal in such disorders. Exploring the functional brain …

Registration Of In-Vivo To Ex-Vivo Mri Of Surgically Resected Specimens: A Pipeline For Histology To In-Vivo Registration., Maged Goubran, Sandrine De Ribaupierre, Robert R Hammond, Catherine Currie, Jorge G Burneo, Andrew G Parrent, Terry M Peters, Ali R Khan

Robarts Imaging Publications

BACKGROUND: Advances in MRI have the potential to improve surgical treatment of epilepsy through improved identification and delineation of lesions. However, validation is currently needed to investigate histopathological correlates of these new imaging techniques. The purpose of this work is to develop and evaluate a protocol for deformable image registration of in-vivo to ex-vivo resected brain specimen MRI. This protocol, in conjunction with our previous work on ex-vivo to histology registration, completes a registration pipeline for histology to in-vivo MRI, enabling voxel-based validation of novel and existing MRI techniques with histopathology.

NEW METHOD: A combination of image-based and landmark-based 3D …

Modification And Evaluation Of A Brain Computer Interface System To Detect Motor Intention, Christopher V. Hagerty-Hoff

Theses and Dissertations

It is widely understood that neurons within the brain produce electrical activity, and electroencephalography—a technique used to measure biopotentials with electrodes placed upon the scalp—has been used to observe it. Today, scientists and engineers work to interface these electrical neural signals with computers and machines through the field of Brain-Computer Interfacing (BCI). BCI systems have the potential to greatly improve the quality of life of physically handicapped individuals by replacing or assisting missing or debilitated motor functions. This research thus aims to further improve the efficacy of the BCI based assistive technologies used to aid physically disabled individuals. This study …

Neuroimaging And Neuromodulation Approaches To Study Eating Behavior And Prevent And Treat Eating Disorders And Obesity, D. Val-Laillet, E. Aarts, B. Weber, M. Ferrari, V. Quaresima, L. E. Stoeckel, M. Alonso-Alonso, M. Audette, C. H. Malbert, E. Stice

Computational Modeling & Simulation Engineering Faculty Publications

Functional, molecular and genetic neuroimaging has highlighted the existence of brain anomalies and neural vulnerability factors related to obesity and eating disorders such as binge eating or anorexia nervosa. In particular, decreased basal metabolism in the prefrontal cortex and striatum as well as dopaminergic alterations have been described in obese subjects, in parallel with increased activation of reward brain areas in response to palatable food cues. Elevated reward region responsivity may trigger food craving and predict future weight gain. This opens the way to prevention studies using functional and molecular neuroimaging to perform early diagnostics and to phenotype subjects at …

A Comparative Study Of Two Prediction Models For Brain Tumor Progression, Deqi Zhou, Loc Tran, Jihong Wang, Jiang Li, Karen O. Egiazarian (Ed.), Sos S. Agaian (Ed.), Atanas P. Gotchev (Ed.)

Electrical & Computer Engineering Faculty Publications

MR diffusion tensor imaging (DTI) technique together with traditional T1 or T2 weighted MRI scans supplies rich information sources for brain cancer diagnoses. These images form large-scale, high-dimensional data sets. Due to the fact that significant correlations exist among these images, we assume low-dimensional geometry data structures (manifolds) are embedded in the high-dimensional space. Those manifolds might be hidden from radiologists because it is challenging for human experts to interpret high-dimensional data. Identification of the manifold is a critical step for successfully analyzing multimodal MR images.

We have developed various manifold learning algorithms (Tran et al. 2011; Tran et al. …

Application And Histology-Driven Refinement Of Active Contour Models To Functional Region And Nerve Delineation: Towards A Digital Brainstem Atlas, Nimal Patel, Sharmin Sultana, Tanweer Rashid, Dean Krusienski, Michel A. Audette

Electrical & Computer Engineering Faculty Publications

This paper presents a methodology for the digital formatting of a printed atlas of the brainstem and the delineation of cranial nerves from this digital atlas. It also describes on-going work on the 3D resampling and refinement of the 2D functional regions and nerve contours. In MRI-based anatomical modeling for neurosurgery planning and simulation, the complexity of the functional anatomy entails a digital atlas approach, rather than less descriptive voxel or surface-based approaches. However, there is an insufficiency of descriptive digital atlases, in particular of the brainstem. Our approach proceeds from a series of numbered, contour-based sketches coinciding with slices …

Technical Note: Phantom Study To Evaluate The Dose And Image Quality Effects Of A Computed Tomography Organ-Based Tube Current Modulation Technique, Diksha Gandhi, Dominic J. Crotty, Grant M. Stevens, Taly Gilat Schmidt

Biomedical Engineering Faculty Research and Publications

Purpose

This technical note quantifies the dose and image quality performance of a clinically available organ-dose-based tube current modulation (ODM) technique, using experimental and simulation phantom studies. The investigated ODM implementation reduces the tube current for the anterior source positions, without increasing current for posterior positions, although such an approach was also evaluated for comparison.

Methods

Axial CT scans at 120 kV were performed on head and chest phantoms on an ODM-equipped scanner (Optima CT660, GE Healthcare, Chalfont St. Giles, England). Dosimeters quantified dose to breast, lung, heart, spine, eye lens, and brain regions for ODM and 3D-modulation (SmartmA) settings. …

A NTh-Order Linear Algorithm For Extracting Diffuse Correlation Spectroscopy Blood Flow Indices In Heterogeneous Tissues, Yu Shang, Guoqiang Yu

Biomedical Engineering Faculty Publications

Conventional semi-infinite analytical solutions of correlation diffusion equation may lead to errors when calculating blood flow index (BFI) from diffuse correlation spectroscopy (DCS) measurements in tissues with irregular geometries. Very recently, we created an algorithm integrating a Nth-order linear model of autocorrelation function with the Monte Carlo simulation of photon migrations in homogenous tissues with arbitrary geometries for extraction of BFI (i.e., αD_B ). The purpose of this study is to extend the capability of the Nth-order linear algorithm for extracting BFI in heterogeneous tissues with arbitrary geometries. The previous linear algorithm was modified to extract BFIs …

Stationary Wavelet Transform For Under-Sampled Mri Reconstruction., Mohammad H Kayvanrad, A Jonathan Mcleod, John S H Baxter, Charles A Mckenzie, Terry M Peters

Robarts Imaging Publications

In addition to coil sensitivity data (parallel imaging), sparsity constraints are often used as an additional lp-penalty for under-sampled MRI reconstruction (compressed sensing). Penalizing the traditional decimated wavelet transform (DWT) coefficients, however, results in visual pseudo-Gibbs artifacts, some of which are attributed to the lack of translation invariance of the wavelet basis. We show that these artifacts can be greatly reduced by penalizing the translation-invariant stationary wavelet transform (SWT) coefficients. This holds with various additional reconstruction constraints, including coil sensitivity profiles and total variation. Additionally, SWT reconstructions result in lower error values and faster convergence compared to DWT. These concepts …

Nonlinear Granger Causality And Its Application In Decoding Of Human Reaching Intentions, Mengting Liu

Doctoral Dissertations

Multi-electrode recording is a key technology that allows the brain mechanisms of decision making, cognition, and their breakdown in diseases to be studied from a network perspective. As the hypotheses concerning the role of neural interactions in cognitive paradigms become increasingly more elaborate, the ability to evaluate the direction of neural interactions in neural networks holds the key to distinguishing their functional significance.

Granger Causality (GC) is used to detect the directional influence of signals between multiple locations. To extract the nonlinear directional flow, GC was completed through a nonlinear predictive approach using radial basis functions (RBF). Furthermore, to obtain …

Controlling Dimensionality In A Systems Approach To Dynamic Multimodal Functional Brain Imaging, Srinivas Laxminarayan, Manu Ben Jonny, Solomon Diamond, Dana Brooks, Gilead Tadmore, Eric Miller, David Boas

Dana Brooks

The complementary spatial, temporal and specificity advantages of MRI, EEG, MEG, PET and DOT for functional brain imaging motivate interest in multimodal functional brain imaging. State-variable dynamical systems modeling of neural activity and its relation to local hemodynamics further coupled with autonomic physiology offers enhanced spatiotemporal resolution and insight into physiological signals and mechanisms. However, such a model also implies an explosion of state dimension. We discuss strategies for controlling this high dimensionality based on subspace approaches applied to the observed data and the model structure, and also describe some implications for understanding human brain function.

'Omic' Evaluation Of The Region Specific Changes Induced By Non-Cholinergic Diisopropylfluorophosphate (Dfp) Exposure In Fischer 344 Rat Brain, Deirdre A. Mahle

Browse all Theses and Dissertations

Organophosphorous compounds (OPs) are a class of serine esterase inhibitors that have widespread application as pesticides, veterinary pharmaceuticals and chemical warfare agents. Environmental contamination is ubiquitous. The threat of exposure is a concern for both military and civilian populations. Acute inhibition of acetylcholinesterase by OPs triggers a cholinergic crisis that results in muscle flaccidity, paralysis, convulsions and death. At low doses OPs can alter neuronal differentiation, cell signaling, behavior and cognition through unknown mechanisms. An imbalance of reactive oxygen species may be implicated in the adverse effects of OPs. An integrated approach using both metabolomic and transcriptomic techniques was used …

Investigation Of Spatio-Temporal Effects Of Fmri Visual Field Mapping Techniques On V1, John J. Janik

Dissertations (1934 -)

Blood oxygenation level dependent functional magnetic resonance imaging has been used extensively for mapping the representation of the visual field within the human brain. Visual field mapping using fMRI has been used clinically to assess patients with cortical pathology and to plan surgical treatment impacting the visual system. The accuracy of fMRI-based visual field mapping methods needs to be better understood for clinical use. This accuracy can be important for presurgical mapping of brain function near a tumor resection site since inaccurate rendition of the underlying neural function could lead to inappropriate resection of viable brain tissue. The most widely …