Biomedical Engineering and Bioengineering Commons^™

Estimating Affective States In Virtual Reality Environments Using The Electroencephalogram, Meghan R. Kumar

Theses and Dissertations

Recent interest in high-performance virtual reality (VR) headsets has motivated research efforts to increase the user's sense of immersion via feedback of physiological measures. This work presents the use of electroencephalographic (EEG) measurements during observation of immersive VR videos to estimate the user's affective state. The EEG of 30 participants were recorded as each passively viewed a series of one minute immersive VR video clips and subjectively rated their level of valence, arousal, dominance, and liking. Correlates between EEG spectral bands and the subjective ratings were analyzed to identify statistically significant frequencies and electrode locations across participants. Model feasibility and …

Effect Of Stimulus Waveform On Transcranial Magnetic Stimulation Metrics In Proximal And Distal Arm Muscles, Christopher Lynch

Theses and Dissertations

Objectives: The purpose of this study was to determine the effect of common transcranial magnetic stimulation (TMS) waveforms (monophasic and biphasic) on resting motor threshold (RMT), active motor threshold (AMT), and motor evoked potential (MEP) amplitudes in the biceps and first dorsal interosseous (FDI) because waveforms may affect motor targets differently. Additionally, we determined the test-retest reliability of TMS metrics for each stimulation type and muscle.

Methods: Ten individuals participated in two sessions of single-pulse TMS delivered to the motor cortex perpendicular to the central sulcus. MEPs were normalized to the maximum EMG signal during contraction and were recorded at …

Novel Tools For Analysis Of Disordered Sleep And Motor Behavior In Preclinical Models Of Disease, Dillon M. Huffman

Theses and Dissertations--Biomedical Engineering

Subtle changes in sleep architecture can accompany and be symptomatic of various diseases or disorders. Understanding the complex interactions between sleep and health requires the ability to characterize sleep, probe its underlying mechanisms through perturbation, and quantify dependent physiological outcomes. Rodent models have come to be accepted as a valuable tool for preclinical investigations. However, experimental tools to accomplish such research typically rely on laborious methods that limit throughput and flexibility. Thus, research tools that minimize workload could be of great value to the research community and expedite investigation of the underlying mechanisms of sleep and further the development of …

Changes In Cardiovascular, Respiratory, And Neural Activity By Music: Effects Of Breathing Pathway On Feeling Emotions, Mohammad Javad Mollakazemi

Theses and Dissertations--Biomedical Engineering

Listening to music can induce emotional and physiological changes. Increasing recognition of the palliative effects of music has led to its use as an adjuvant therapeutic tool in the treatment of various diseases. It is also well known that autonomic nervous activities and some cardiorespiratory rhythms change in correspondence with music. However, less is known about how these effects triggered by music come about. Listening to music affects synchronization between electroencephalograms (EEGs) and cardiac rhythmic activity. This interaction between cardiac and electrical responses led us to investigate whether EEG segments synchronized to different portions of the cardiac cycle can better …

Electroporation Safety Factor Of 300 Nanosecond And 10 Millisecond Defibrillation In Langendorff-Perfused Rabbit Hearts, Johanna U. Neuber, Andrei G. Pakhomov, Christian W. Zemlin

Bioelectrics Publications

Aims

Recently, a new defibrillation modality using nanosecond pulses was shown to be effective at much lower energies than conventional 10 millisecond monophasic shocks in ex vivo experiments. Here we compare the safety factors of 300 nanosecond and 10 millisecond shocks to assess the safety of nanosecond defibrillation.

Methods and results

The safety factor, i.e. the ratio of median effective doses (ED50) for electroporative damage and defibrillation, was assessed for nanosecond and conventional (millisecond) defibrillation shocks in Langendorff-perfused New Zealand white rabbit hearts. In order to allow for multiple shock applications in a single heart, a pair of needle electrodes …

Bio-Inspired Materials For Electrochemical Sensors, Matthew Joseph Hummel

Electronic Theses and Dissertations

Electrochemical biosensors are a rapidly growing research area that has greatly improved its specificity, accuracy, and precision in the detection of biomolecules in contemporary literature and industry alike. Typically, these systems exist in a three-electrode conformation with a working electrode functioning as the anode, a counter electrode functioning as the cathode, and a reference electrode allowing for the control of potential in the system. The method by which these sensors work is through the sharing of electrons via redox reactions with the target molecule and the working electrode or modifications on its surface. By exploiting the function of biomaterials that …

Sex-Related Differences In Murine Models Of Chemically Induced Pulmonary Fibrosis, Pavel Solopov, Ruben Manuel Luciano Colunga Biancatelli, Christiana Dimitropoulou, John D. Catravas

Bioelectrics Publications

We developed two models of chemically induced chronic lung injury and pulmonary fibrosis in mice (intratracheally administered hydrochloric acid (HCl) and intratracheally administered nitrogen mustard (NM)) and investigated male-female differences. Female mice exhibited higher 30-day survival and less weight loss than male mice. Thirty days after the instillation of either HCl or NM, bronchoalveolar lavage fluid displayed a persistent, mild inflammatory response, but with higher white blood cell numbers and total protein content in males vs. females. Furthermore, females exhibited less collagen deposition, milder pulmonary fibrosis, and lower Ashcroft scores. After instillation of either HCl or NM, all animals displayed …

Age-Dependent Chronic Lung Injury And Pulmonary Fibrosis Following Single Exposure To Hydrochloric Acid, Ruben M.L. Colunga Biancatelli, Pavel Solopov, Christiana Dimitropoulou, John D. Catravas

Bioelectrics Publications

Exposure to hydrochloric acid (HCl) represents a threat to public health. Children may inhale higher doses and develop greater injury because of their smaller airways and faster respiratory rate. We have developed a mouse model of pediatric exposure to HCl by intratracheally instilling p24 mice (mice 24 days old; 8–10 g) with 2 µL/g 0.1 N HCl, and compared the profile of lung injury to that in HCl-instilled adults (10 weeks old; 25–30 g) and their age-matched saline controls. After 30 days, alveolar inflammation was observed with increased proteinosis and mononuclear cells in the bronchoalveolar lavage fluid (BALF) in both …

Ecg Monitoring In Athletes, Jalal Jwayyed, Kelly Purgason, Joseph Linder, Annamarie Alfery, Silvia Furman

Williams Honors College, Honors Research Projects

Athletes and medical personnel need reliable methods to monitor vital signs and detect potentially life-threatening issues before they occur. Electrocardiograph (ECG) monitors are currently the best method of detecting heart-related health issues. Current ECG monitors worn by athletes are difficult to use and lack the ability to track ECGs in real time. Through research and interviews with various clinicians, further problems have been identified that include poor electrode adhesion, and a lack of compatibility with the equipment worn by athletes. Our team proposes to develop solutions that will improve performance and comfort associated with ECG monitors for athletic applications. This …

Machine Learning Approach For Vigilance State Classification In Mice, Anik Muhury

Theses and Dissertations--Electrical and Computer Engineering

Sleep has a significant impact on cognitive abilities such as memory, reaction time, productivity, and creative thinking; however, there are many aspects of this important activity that are not clearly understood. Over the last century, researchers have developed technology and animal models to assist in the study of sleep. Manual sleep scoring is time consuming, reduces productivity, and is impacted by human scorer subjectivity. On the other hand, automatic sleep stage categorization can enhance consistency and reliability, aiding professionals in identifying sleep related health problems.

In recent times various studies reported significant achievements for automatic vigilance detection and overcome the …

Evaluating Neuromuscular Function Of The Biceps Brachii After Spinal Cord Injury: Assessment Of Voluntary Activation And Motor Evoked Potential Input-Output Curves Using Transcranial Magnetic Stimulation, Thibault Roumengous

Theses and Dissertations

Activation of upper limb muscles is important for independent living after cervical spinal cord injury (SCI) that results in tetraplegia. An emerging, non-invasive approach to address post-SCI muscle weakness is modulation of the nervous system. A long-term goal is to develop neuromodulation techniques to reinnervate (i.e. resupply nerve to) muscle fiber and thereby increase muscle function in individuals with tetraplegia. Towards this goal, developing monitoring techniques to quantify neuromuscular function is needed to better direct neurorehabilitation. Assessment of voluntary activation (VA) is a promising approach because the location of the stimulus can be applied cortically using transcranial magnetic stimulation (TMS) …

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 …

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 …

Cold Atmospheric-Pressure Plasma Caused Protein Damage In Methicillin-Resistant Staphylococcus Aureus Cells In Biofilms, Li Guo, Lu Yang, Yu Qi, Gulimire Niyazi, Lingling Huang, Lu Gou, Zifeng Wang, Lei Zhang, Dingxin Liu, Xiaohua Wang, Hailan Chen, Michael G. Kong

Bioelectrics Publications

Biofilms formed by multidrug-resistant bacteria are a major cause of hospital-acquired infections. Cold atmospheric-pressure plasma (CAP) is attractive for sterilization, especially to disrupt biofilms formed by multidrug-resistant bacteria. However, the underlying molecular mechanism is not clear. In this study, CAP effectively reduced the living cells in the biofilms formed by methicillin-resistant Staphylococcus aureus, and 6 min treatment with CAP reduced the S. aureus cells in biofilms by 3.5 log₁₀. The treatment with CAP caused the polymerization of SaFtsZ and SaClpP proteins in the S. aureus cells of the biofilms. In vitro analysis demonstrated that recombinant SaFtsZ lost …

Connexin Hemichannel Activation By S-Nitrosoglutathione Synergizes Strongly With Photodynamic Therapy Potentiating Anti-Tumor Bystander Killing, Chiara Nardin, Chiara Peres, Sabrina Putti, Tiziana Orsini, Claudia Colussi, Flavia Mazzarda, Marcello Raspa, Ferdinando Scavizzi, Anna Maria Salvatore, Francesco Chiani, Abraham Tettey-Matey, Yuanyuan Kuang, Guang Yang, Mauricio A. Retamal, Fabio Mammano

Bioelectrics Publications

In this study, we used B16-F10 cells grown in the dorsal skinfold chamber (DSC) preparation that allowed us to gain optical access to the processes triggered by photodynamic therapy (PDT). Partial irradiation of a photosensitized melanoma triggered cell death in non-irradiated tumor cells. Multiphoton intravital microscopy with genetically encoded fluorescence indicators revealed that bystander cell death was mediated by paracrine signaling due to adenosine triphosphate (ATP) release from connexin (Cx) hemichannels (HCs). Intercellular calcium (Ca²⁺) waves propagated from irradiated to bystander cells promoting intracellular Ca²⁺ transfer from the endoplasmic reticulum (ER) to mitochondria and rapid activation of …

Intermittent Theta Burst Stimulation: Application To Spinal Cord Injury Rehabilitation And Computational Modeling, Neil Mittal

Theses and Dissertations

Loss of motor function from spinal cord injuries (SCI) results in loss of independence. Rehabilitation efforts are targeted to enhance the ability to perform activities of daily living (ADLs), but outcomes from physical therapy alone are often insufficient. Neuromodulation techniques that induce neuroplasticity may push the limits on recovery. Neuromodulation by intermittent theta burst transcranial magnetic stimulation (iTBS) induces neuroplasticity by increasing corticomotor excitability, though this has most frequently been studied with motor targets and on individuals not in need of rehabilitation. Increased corticomotor excitability is associated with motor learning. The response to iTBS, however, is highly variable and unpredictable, …

Network-Level Mechanisms Underlying Effects Of Transcranial Direct Current Stimulation (Tdcs) On Visuomotor Learning, Pejman Sehatpour, Clément Dondé, Matthew J. Hoptman, Johanna Kreither, Devin Adair, Elisa Dias, Blair Vail, Stephanie Rohrig, Gail Silipo, Javier Lopez-Calderon, Antigona Martinez, Daniel C. Javitt

Publications and Research

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation approach in which low level currents are administered over the scalp to influence underlying brain function. Prevailing theories of tDCS focus on modulation of excitation-inhibition balance at the local stimulation location. However, network level effects are reported as well, and appear to depend upon differential underlying mechanisms. Here, we evaluated potential network-level effects of tDCS during the Serial Reaction Time Task (SRTT) using convergent EEG- and fMRI-based connectivity approaches. Motor learning manifested as a significant (p <.0001) shift from slow to fast responses and corresponded to a significant increase in beta-coherence (p <.0001) and fMRI connectivity (p <.01) particularly within the visual-motor pathway. Differential patterns of tDCS effect were observed within different parametric task versions, consistent with network models. Overall, these findings demonstrate objective physiological effects of tDCS at the network level that result in effective behavioral modulation when tDCS parameters are matched to network-level requirements of the underlying task.

Update On The Use Of Transcranial Electrical Brain Stimulation To Manage Acute And Chronic Covid-19 Symptoms, Giuseppina Pilloni, Marom Bikson, Bashar W. Badran, Mark S. George, Steven A. Kautz, Alexandre Hideki Okano, Abrahão Fontes Baptista, Leigh E. Charvet

Publications and Research

The coronavirus disease 19 (COVID-19) pandemic has resulted in the urgent need to develop and deploy treatment approaches that can minimize mortality and morbidity. As infection, resulting illness, and the often prolonged recovery period continue to be characterized, therapeutic roles for transcranial electrical stimulation (tES) have emerged as promising non-pharmacological interventions. tES techniques have established therapeutic potential for managing a range of conditions relevant to COVID-19 illness and recovery, and may further be relevant for the general management of increased mental health problems during this time. Furthermore, these tES techniques can be inexpensive, portable, and allow for trained self-administration. Here, …

Characterization Of Neuronal Differentiation And Activity In Human-Induced Pluripotent Neural Stem Cells, Allison Biddinger

The Journal of Purdue Undergraduate Research

No abstract provided.

Admittance Method For Estimating Local Field Potentials Generated In A Multi-Scale Neuron Model Of The Hippocampus, Clayton S. Bingham, Javad Paknahad, Christopher Bc Girard, Kyle Loizos, Jean-Marie C. Bouteiller, Dong Song, Gianluca Lazzi, Theodore W. Berger

Engineering Faculty Articles and Research

Significant progress has been made toward model-based prediction of neral tissue activation in response to extracellular electrical stimulation, but challenges remain in the accurate and efficient estimation of distributed local field potentials (LFP). Analytical methods of estimating electric fields are a first-order approximation that may be suitable for model validation, but they are computationally expensive and cannot accurately capture boundary conditions in heterogeneous tissue. While there are many appropriate numerical methods of solving electric fields in neural tissue models, there isn't an established standard for mesh geometry nor a well-known rule for handling any mismatch in spatial resolution. Moreover, the …

Detection Of Standing And Sitting Variations Based On In-Socket Piezoelectric Sensors For Transfemoral Amputees, Alnusairi Tawfik Yahya

Student Works (2020-2029)

A transfemoral prosthesis is required to assist amputees to perform activities of daily living (ADL). The purely mechanical or passive prosthesis has some drawbacks such as consumption of high metabolic energy and limitations in mimicking normal dynamics and kinematics of gait pattern. In contrast, the active prosthesis offers better performance and consumes less metabolic energy. However, recent active prosthesis uses surface electromyography as its sensory system which requires massive preparation work, causes sores to the patient by its electrodes and requires a lot of computation to extract meaningful features. This thesis focuses on developing signal conditioning circuitry to classify six …

Validation Of Nanosecond Pulse Cancellation Using A Quadrupole Exposure System, Hollie A. Ryan

Biomedical Engineering Theses & Dissertations

Nanosecond pulsed electric fields (nsPEFs) offer a plethora of opportunities for developing integrative technologies as complements or alternatives to traditional medicine. Studies on the biological effects of nsPEFs in vitro and in vivo have revealed unique characteristics that suggest the potential for minimized risk of complications in patients, such as the ability of unipolar nsEPs to create permanent or transient pores in cell membranes that trigger localized lethal or non-lethal outcomes without consequential heating. A more recent finding was that such responses could be diminished by applying a bipolar pulse instead, a phenomenon dubbed bipolar cancellation, paving the way …

Visually Evoked Responses Are Enhanced When Engaging In A Video Game, Jason J. Ki, Lucas C. Parra, Jacek P. Dmochowski

Publications and Research

While it is well known that vision guides movement, less appreciated is that the motor cortex also provides input to the visual system. Here, we asked whether neural processing of visual stimuli is acutely modulated during motor activity, hypothesizing that visual evoked responses are enhanced when engaged in a motor task that depends on the visual stimulus. To test this, we told participants that their brain activity was controlling a video game that was in fact the playback of a prerecorded game. The deception, which was effective in half of participants, aimed to engage the motor system while avoiding evoked …

Secretion Of Proteins And Antibody Fragments From Transiently Transfected Endothelial Progenitor Cells, Loree Heller, Reynald Thinard, Melanie Chevalier, Sezgi Arpag, Yu Jing, Ruth Greferath, Richard Heller, Claude Nicolau

Bioelectrics Publications

In neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, multiple sclerosis and amyotrophic lateral sclerosis, neuroinflammation can lead to blood-brain barrier (BBB) breakdown. After intravenous or intra-arterial injection into mice, endothelial progenitor cells (EPCs) home to the damaged BBB to promote neurovascular repair. Autologous EPCs transfected to express specific therapeutic proteins offer an innovative therapeutic option. Here, we demonstrate that EPC transfection by electroporation with plasmids encoding the reporter protein GFP or an anti-beta-amyloid antibody fragment (Fab) leads to secretion of each protein. We also demonstrate the secreted anti-beta-amyloid Fab protein functions in beta-amyloid aggregate solubilization.

Functional Connectivity Of Eeg Is Subject-Specific, Associated With Phenotype, And Different From Fmri, Maximilian Nentwich, Lei Ai, Jens Madsen, Qawi K. Telesford, Stefan Haufe, Michael P. Milham, Lucas C. Parra

Publications and Research

A variety of psychiatric, behavioral and cognitive phenotypes have been linked to brain ‘’functional connectivity’’ -- the pattern of correlation observed between different brain regions. Most commonly assessed using functional magnetic resonance imaging (fMRI), here, we investigate the connectivity-phenotype associations with functional connectivity measured with electroencephalography (EEG), using phase-coupling. We analyzed data from the publicly available Healthy Brain Network Biobank. This database compiles a growing sample of children and adolescents, currently encompassing 1657 individuals. Among a variety of assessment instruments we focus on ten phenotypic and additional demographic measures that capture most of the variance in this sample. The largest …

Can Transcranial Electrical Stimulation Motor Threshold Estimate Individualized Tdcs Doses Over The Prefrontal Cortex? Evidence From Reverse-Calculation Electric Field Modeling, Kevin A. Caulfield, Bashar W. Badran, Xingbao Li, Marom Bikson, Mark S. George

Publications and Research

No abstract provided.

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. …

Probing Nanoelectroporation And Resealing Of The Cell Membrane By The Entry Of Ca2+ And Ba2+ Ions, Wenfei Bo, Mantas Silkunas, Uma Mangalanathan, Vitalij Novickij, Maura Casciola, Iurii Semenov, Shu Xiao, Olga N. Pakhomova, Andrei G. Pakhomov

Bioelectrics Publications

The principal bioeffect of the nanosecond pulsed electric field (nsPEF) is a lasting cell membrane permeabilization, which is often attributed to the formation of nanometer-sized pores. Such pores may be too small for detection by the uptake of fluorescent dyes. We tested if Ca²⁺, Cd²⁺, Zn²⁺, and Ba²⁺ ions can be used as nanoporation markers. Time-lapse imaging was performed in CHO, BPAE, and HEK cells loaded with Fluo-4, Calbryte, or Fluo-8 dyes. Ca²⁺ and Ba²⁺ did not change fluorescence in intact cells, whereas their entry after nsPEF increased fluorescence within <1 ms. The threshold for one 300-ns pulse was at 1.5–2 kV/cm, much lower than >7 …

Mechanical Analysis Of In Vitro Tbi Models, Dana Hamed

Honors Scholar Theses

This work details the damage done to cells when mechanically hit. The goal was to mechanically analyze in vitro traumatic brain injury (TBI) models. Parts were designed in SolidWorks to create the machine that is used to induce this damage on the cells. A force applicator that uses a 3D-printed micro-hammer to apply force on the brain cells that are being tested was created. Mechanical trauma experimentation was performed with the force applicator, while a high-speed camera recorded the damage, in order to analyze TBI models. Displacement along the scaffold can be tracked from multiple video frames. With these results, …

Transcranial Electrical Stimulation Motor Threshold Can Estimate Individualized Tdcs Dosage From Reverse-Calculation Electric-Field Modeling, Kevin A. Caulfield, Bashar W. Badran, William H. Devries, Philipp M. Summers, Emma Kofmehl, Xingbao Li, Jeffrey J. Borckardt, Marom Bikson, Mark S. George

Publications and Research

Background

Unique amongst brain stimulation tools, transcranial direct current stimulation (tDCS) currently lacks an easy or widely implemented method for individualizing dosage.

Objective

We developed a method of reverse-calculating electric-field (E-field) models based on Magnetic Resonance Imaging (MRI) scans that can estimate individualized tDCS dose. We also evaluated an MRI-free method of individualizing tDCS dose by measuring transcranial magnetic stimulation (TMS) motor threshold (MT) and single pulse, suprathreshold transcranial electrical stimulation (TES) MT and regressing it against E-field modeling. Key assumptions of reverse-calculation E-field modeling, including the size of region of interest (ROI) analysis and the linearity of multiple E-field …