Bioelectrical and Neuroengineering Commons^™

Bioelectrical Circuits: Lecture 1, Jacek P. Dmochowski, Luis Cardoso

Open Educational Resources

No abstract provided.

Bioelectrical Circuits: Lecture 3, Jacek P. Dmochowski, Luis Cardoso

Open Educational Resources

No abstract provided.

Initiation Of Action Potential In Murine Ventricular Myocytes By Bursts Of Nanosecond Pulses, Iurii Semenov

Bioelectrics Publications

[First slide] Current situation

I. Among 300,000 persons die from sudden cardiac arrest every year over 40% are victims of fibrillation

II. Defibrillation by an electric shock is the effective therapy against sudden cardiac death

III. Current approach to stop fibrillation may involve disruption of plasma membrane (PM) by an electroporation

IV. Electroporation is damaging, it can: I. Induce post shock arrhythmias II. Complicate patient's recovery III. Lead to death after initially successful resuscitation

A Brain-Computer Interface For Closed-Loop Sensory Stimulation During Motor Training In Patients With Tetraplegia, Sarah Helen Thomas

Theses and Dissertations--Biomedical Engineering

Normal movement execution requires proper coupling of motor and sensory activation. An increasing body of literature supports the idea that incorporation of sensory stimulation into motor rehabilitation practices increases its effectiveness. Paired associative stimulation (PAS) studies, in which afferent and efferent pathways are activated in tandem, have brought attention to the importance of well-timed stimulation rather than non-associative (i.e., open-loop) activation. In patients with tetraplegia resulting from spinal cord injury (SCI), varying degrees of upper limb function may remain and could be harnessed for rehabilitation. Incorporating associative sensory stimulation coupled with self-paced motor training would be a means for supplementing …

A Possible Link Between R-Wave Amplitude Alternans And T-Wave Alternans In Ecgs, Sahar Alaei

Theses and Dissertations--Biomedical Engineering

Sudden Cardiac Death (SCD) is the largest cause of natural deaths in the USA, accounting for over 300,000 deaths annually. The major reason for SCD is Ventricular Arrhythmia (VA). Therefore, there is need for exploration of approaches to predict increased risk for VA. Alternans of the T wave in the ECG (TWA) is widely investigated as a potential predictor of VA, however, clinical trials show that TWA has high negative predictive value but poor positive predictive value. A possible reason that TWA has a large number of false positives is that a pattern of alternans known as concordant alternans, may …

Translational Modeling Of Non-Invasive Electrical Stimulation, Dennis Quangvinh Truong

Dissertations and Theses

Seminal work in the early 2000’s demonstrated the effect of low amplitude non-invasive electrical stimulation in people using neurophysiological measures (motor evoked potentials, MEPs). Clinical applications of transcranial Direct Current Stimulation (tDCS) have since proliferated, though the mechanisms are not fully understood. Efforts to refine the technique to improve results are on-going as are mechanistic studies both in vivo and in vitro. Volume conduction models are being applied to these areas of research, especially in the design and analysis of clinical montages. However, additional research on the parameterization of models remains.

In this dissertation, Finite Element Method (FEM) models of …

Nanosecond Pulsed Electric Signals Can Affect Electrostatic Environment Of Protiens Below The Threshold Of Conformational Effects: The Case Study Of Sod1 With A Molecular Simulation Study, Elena Della Valle, Paolo Marracino, Olga Pakhomova, Micaela Liberti, Francesca Apollonio

Bioelectrics Publications

Electric fields can be a powerful tool to interact with enzymes or proteins, with an intriguing perspective to allow protein manipulation. Recently, researchers have focused the interest on intracellular enzyme modifications triggered by the application of nanosecond pulsed electric fields. These findings were also supported by theoretical predictions from molecular dynamics simulations focussing on significant variations in protein secondary structures. In this work, a theoretical study utilizing molecular dynamics simulations is proposed to explore effects of electric fields of high intensity and very short nanosecond duration applied to the superoxide dismutase (Cu/Zn-SOD or SOD-1), an important enzyme involved in the …

Design And Testing Of An Agonist-Antagonist Position-Impedance Controlled Myoelectric Prosthesis, Christopher Aymonin

Theses and Dissertations

Intuitive prosthetic control is limited by the inability to easily convey intention and perceive physical requirements of the task. Rather than providing haptic feedback and allowing users to consciously control every component of manipulation, relegating some aspects of control to the device may simplify operation. This study focuses on the development and testing of a control scheme able to identify object stiffness and regulate impedance. The system includes an algorithm to detect the apparent stiffness of an object, a proportional nonlinear EMG control algorithm for interpreting a user’s desired grasp aperture, and an antagonistically acting impedance controller. Performance of a …

Modeling And Simulation Methodologies For Spinal Cord Stimulation., Saliya Kumara Kirigeeganage

Electronic Theses and Dissertations

The use of neural prostheses to improve health of paraplegics has been a prime interest of neuroscientists over the last few decades. Scientists have performed experiments with spinal cord stimulation (SCS) to enable voluntary motor function of paralyzed patients. However, the experimentation on the human spinal cord is not a trivial task. Therefore, modeling and simulation techniques play a significant role in understanding the underlying concepts and mechanics of the spinal cord stimulation. In this work, simulation and modeling techniques related to spinal cord stimulation were investigated. The initial work was intended to visualize the electric field distribution patterns in …

Voltage Effects On Muscarinic Acetylcholine Receptor-Mediated Contractions Of Airway Smooth Muscle, Iurii Semenov, Robert Brenner

Bioelectrics Publications

Studies have shown that the activity of muscarinic receptors and their affinity to agonists are sensitive to membrane potential. It was reported that in airway smooth muscle (ASM) depolarization evoked by high K⁺ solution increases contractility through direct effects on M3 muscarinic receptors. In this study, we assessed the physiological relevance of voltage sensitivity of muscarinic receptors on ASM contractility. Our findings reveal that depolarization by high K⁺ solution induces contraction in intact mouse trachea predominantly through activation of acetylcholine release from embedded nerves, and to a lesser extent by direct effects on M3 receptors. We therefore devised …

Neural Coding Of An Auditory Pitch Illusion, Maria Alejandra Barrera, Mark Sayles, Ravinderjit Singh

The Summer Undergraduate Research Fellowship (SURF) Symposium

Pitch is an important perceptual dimension in audition, supporting auditory object segregation, melody recognition and lexical distinction. Huggins’ pitch, for example, is a phenomenon evoked by two sources of broadband noise presented binaurally with an inter-aural phase shift over a narrow frequency band. Huggins’ pitch and other dichotic pitches have been studied extensively using perceptual experiments. Several models have been proposed to explain and predict the perception of pitch; however, no studies have tried to record in vivo neuron responses to Huggins’ pitch (HP) nor have tried to explain how the HP is coded by neurons. The existence of pitches …

Non-Invasive Diagnostic Measures Of Sensorineural Hearing Loss In Chinchillas, Hannah M. Ginsberg, Satyabrata Parida, Michael G. Heinz

The Summer Undergraduate Research Fellowship (SURF) Symposium

According to the World Health Organization, disabling hearing loss affects nearly 466 million people worldwide. Sensorineural hearing loss (SNHL), which is characterized as damage to the inner ear (e.g., cochlear hair cells) and/or to the neural pathways connecting the inner ear and brain, accounts for 90% of all disabling hearing loss. More concerning is that significant perceptual and physiological aspects of SNHL remain “hidden” from standard clinical diagnostics. Hidden hearing loss (HHL) manifests as the inability to understand speech in loud, noisy environments (e.g., listening in a noisy restaurant) despite a normal audiogram (i.e., normal detection of soft sounds). Recently, …

Effects Of 8-Week Sensory Electrical Stimulation Combined With Motor Training On Eeg-Emg Coherence And Motor Function In Individuals With Stroke, Li-Ling Hope Pan, Wen-Wen Yang, Mei-Wun Tsai, Shun-Hwa Wei, Felipe Fregni, Vincent Chiun-Fan Chen, Li-Wei Chou

Engineering Science Faculty Publications

The peripheral sensory system is critical to regulating motor plasticity and motor recovery. Peripheral electrical stimulation (ES) can generate constant and adequate sensory input to influence the excitability of the motor cortex. The aim of this proof of concept study was to assess whether ES prior to each hand function training session for eight weeks can better improve neuromuscular control and hand function in chronic stroke individuals and change electroencephalography-electromyography (EEG-EMG) coherence, as compared to the control (sham ES). We recruited twelve subjects and randomly assigned them into ES and control groups. Both groups received 20-minute hand function training twice …

Neuro-Silicon Interface Of A Hirudo Medicinalis Retzius Cell Integrated With Field Effect Transistor, Kurt Christian Sjoberg

Master's Theses

The focus of this thesis was to measure the intracellular voltage of a living neural cell using a silicon transistor. The coupling of neurological tissues with silicon devices is of interest to the fields of neurology, neuroscience, electrophysiology and cellular biology. In previous work by Peter Fromherz, single neurons were successfully coupled to transistors [1]. This thesis aims to show proof of concept of the fabrication of a simple neuro-silicon interface using wafer processing methods currently available at Cal Poly. The types of transistors and cells used, the methods for dissecting and preparing the cells, the electrophysiology methods for validating …

Intercellular Sodium Nanodomain Signaling Regulates Repolarization In Cardiac Tissue, Madison Nowak, Seth Weinberg Ph.D.

Biology and Medicine Through Mathematics Conference

No abstract provided.

Computational Theories For Human Stereo Vision, Han Gao

Electrical Engineering Theses and Dissertations

Binocular stereopsis refers to the ability to perceive depth, which has always been a central problem in perception since the time of da Vinci. The foremost theoretical difficulty that arises when attempting to understand how the visual system computes disparity is known as the correspondence or matching problem. Decades of research upon macaque primary visual cortex has shown that in each layer of the primary visual cortex (V1) long-range horizontal connections among striate cortex cells exist which integrate information from different parts of the visual field. Inspired by long-range horizontal connections in V1 and the Jeffress model, a time-delay neural …

Chronic Nerve Interfacing Utilizing Graft-Embedded Regenerative Macro-Sieve Electrodes, Amrita Nishtala

McKelvey School of Engineering Graduate Student Theses & Dissertations

Custom-designed macro-sieve electrodes represent a novel means of facilitating chronic high specificity nerve stimulation needed to control distal nerve musculature and restore sensorimotor function. Implantation of these electrodes requires the transection of the nerve, which has shown to disrupt muscle fiber distribution. This present study assesses the feasibility of implementing these electrodes in an end-to-side nerve graft. The macro-sieve electrodes were fabricated and micro-surgically implanted into 3.2 cm nerve autografts harvested from the sciatic nerve of 12 male Lewis rats. Electrode-enabled nerve grafts were micro-surgically implanted in an end-to-side manner into donor rat sciatic nerves without the need for a …

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 …

Longitudinal Tracking Of Physiological State With Electromyographic Signals., Robert Warren Stallard

Electronic Theses and Dissertations

Electrophysiological measurements have been used in recent history to classify instantaneous physiological configurations, e.g., hand gestures. This work investigates the feasibility of working with changes in physiological configurations over time (i.e., longitudinally) using a variety of algorithms from the machine learning domain. We demonstrate a high degree of classification accuracy for a binary classification problem derived from electromyography measurements before and after a 35-day bedrest. The problem difficulty is increased with a more dynamic experiment testing for changes in astronaut sensorimotor performance by taking electromyography and force plate measurements before, during, and after a jump from a small platform. A …

Detecting Suicide Risk From Wristworn Activity Tracker Data Using Machine Learning Approaches, Pallavi Atluri

Electrical Engineering Theses

Suicide is a prevalent cause of death worldwide and depression is a primary concern of many suicidal acts. It is possible that an individual during depression never has any suicidal thoughts at all. On the other hand, some individuals in stable condition with no apparent symptoms of depression feel urges to commit suicide (suicidal ideation). Many such individuals never let anyone know what they are feeling or planning. Suicidal ideation considered an important precursor to suicidal acts.

Detecting the suicide risk in individuals with mood disorders is a major challenge. The current clinical practice to assess suicide risk in these …