The Do-It-Yourself Electrocardiogram.

Unlabelled: Hands-on labs are a critical component of biomedical engineering undergraduate education. Due to both the pandemic and the growing interest in online education, we developed a Do-it-yourself Electrocardiogram (DIY EKG) project. The Arduino-based DIY EKG kit instructed students how to build a circuit to obtain their own EKG and then analyze their EKG data using Matlab.

Enhancement of bilateral cortical somatosensory evoked potentials to intact forelimb stimulation following thoracic contusion spinal cord injury in rats.

The adult central nervous system is capable of significant reorganization and adaptation following neurotrauma. After a thoracic contusive spinal cord injury (SCI) neuropathways that innervate the cord below the epicenter of injury are damaged, with minimal prospects for functional recovery. In contrast, pathways above the site of injury remain intact and may undergo adaptive changes in response to injury.

Band specific changes in thalamocortical synchrony in field potentials after cardiac arrest induced global hypoxia.

Cardiac Arrest (CA) leads to a global hypoxic-ischemic injury in the brain leading to a poor neurological outcome. Understanding the mechanisms of functional disruption in various regions of the brain may be essential for the development of improved diagnostic and therapeutic solutions. Using controlled laboratory experiment with animal models of CA, our primary focus here is on understanding the functional changes in the thalamus and the cortex, associated with the injury and acute recovery upon resuscitation.

Effect of hypothermia on cortical and thalamic signals in anesthetized rats.

Beneficial effects of hypothermia on subjects with neuro-pathologies have been well demonstrated in both animal studies and clinical trials. Although it is known that temperature significantly impacts neurological injuries, the underlying mechanism remains unclear. We studied the effect of temperature modulation on neural signals in the cortex and the thalamus in uninjured brains of anesthetized rats.

Assessing thalamocortical functional connectivity with Granger causality.

Assessment of network connectivity across multiple brain regions is critical to understanding the mechanisms underlying various neurological disorders. Conventional methods for assessing dynamic interactions include cross-correlation and coherence analysis. However, these methods do not reveal the direction of information flow, which is important for studying the highly directional neurological system.

Effect of hypothermia on the thalamocortical function in the rat model.

Neuroprotective effects of hypothermia are well documented in many injuries of the central nervous system in animal models as well as clinical studies. However, the underlying mechanisms are not fully understood. An important yet unexplored background issue is the effect of hypothermic cooling on the regional functionality of the healthy CNS.

Electrophysiological evaluation of sensory and motor pathways after incomplete unilateral spinal cord contusion.

Object: Unilateral contusions represent an increasingly popular model for studying the pathways and recovery mechanisms of spinal cord injury (SCI). Current studies rely heavily on motor behavior scoring and histological evidence to make assessments. Electrophysiology represents one way to reliably quantify the functionality of motor pathways.

Plasticity associated changes in cortical somatosensory evoked potentials following spinal cord injury in rats.

Spinal cord injury (SCI) causes a number of physiological and neurological changes resulting in loss of sensorimotor function. Recent work has shown that the central nervous system is capable of plastic behaviors post-injury, including axonal regrowth and cortical remapping. Functional integrity of afferent sensory pathways can be quantified using cortical somatosensory evoked potentials (SSEPs) recorded upon peripheral limb stimulation.

Potential long-term benefits of acute hypothermia after spinal cord injury: assessments with somatosensory-evoked potentials.

Objective: Neuroprotection by hypothermia has been an important research topic over last two decades. In animal models of spinal cord injury, the primary focus has been assessing the effects of hypothermia on behavioral and histologic outcomes. Although a few studies have investigated electrophysiological changes in descending motor pathways with motor-evoked potentials recorded during cooling, we report here hypothermia induced increased electrical conduction in the ascending spinal cord pathways with somatosensory-evoked potentials in injured rats.

Human glial-restricted progenitors survive, proliferate, and preserve electrophysiological function in rats with focal inflammatory spinal cord demyelination.

Transplantation of glial progenitor cells results in transplant-derived myelination and improved function in rodents with genetic dysmyelination or chemical demyelination. However, glial cell transplantation in adult CNS inflammatory demyelinating models has not been well studied. Here we transplanted human glial-restricted progenitor (hGRP) cells into the spinal cord of adult rats with inflammatory demyelination, and monitored cell fate in chemically immunosuppressed animals.

Connectivity mapping of the human ECoG during a motor task with a time-varying dynamic Bayesian network.

As a partially invasive and clinically obtained neural signal, the electrocorticogram (ECoG) provides a unique opportunity to study cortical processing in humans in vivo. Functional connectivity mapping based on the ECoG signal can provide insight into epileptogenic zones and putative cortical circuits. We describe the first application of time-varying dynamic Bayesian networks (TVDBN) to the ECoG signal for the identification and study of cortical circuits.

Characterization of neurologic injury using novel morphological analysis of Somatosensory Evoked Potentials.

This paper describes an innovative, easy-to-interpret, clinically translatable tool for analysis of Somatosensory Evoked Potentials (SSEPs). Unlike traditional analysis, which involves peak-to-peak amplitude and latency calculation, this method, phase space analysis, analyzes the overall morphology of the SSEP, and includes greater information. The SSEP is plotted in phase space (x-dot vs.

Multi-limb acquisition of motor evoked potentials and its application in spinal cord injury.

The motor evoked potential (MEP) is an electrical response of peripheral neuro-muscular pathways to stimulation of the motor cortex. MEPs provide objective assessment of electrical conduction through the associated neural pathways, and therefore detect disruption due to a nervous system injury such as spinal cord injury (SCI). In our studies of SCI, we developed a novel, multi-channel set-up for MEP acquisition in rat models.

Slope analysis of somatosensory evoked potentials in spinal cord injury for detecting contusion injury and focal demyelination.

In spinal cord injury (SCI) research there is a need for reliable measures to determine the extent of injury and assess progress due to natural recovery, drug therapy, surgical intervention or rehabilitation. Somatosensory evoked potentials (SEP) can be used to quantitatively examine the functionality of the ascending sensory pathways in the spinal cord. A reduction of more than 50% in peak amplitude or an increase of more than 10% in latency are threshold indicators of injury.

Quantitative assessment of somatosensory-evoked potentials after cardiac arrest in rats: prognostication of functional outcomes.

Objective: High incidence of poor neurologic sequelae after resuscitation from cardiac arrest underscores the need for objective electrophysiological markers for assessment and prognosis. This study aims to develop a novel marker based on somatosensory evoked potentials (SSEPs). Normal SSEPs involve thalamocortical circuits suggested to play a role in arousal.

Evoked potential and behavioral outcomes for experimental autoimmune encephalomyelitis in Lewis rats.

A reliable outcome measurement is needed to assess the effects of experimental lesions in the rat spinal cord as well as to assess the benefits of therapies designed to modulate them. The Basso, Beattie, and Bresnahan (BBB) behavioral scores can be indicative of the functionality in motor pathways. However, since lesions are often induced in the more accessible dorsal parts associated with the sensory pathways, the BBB scores may not be ideal measure of the disability.

Multiscale entropy analysis of EEG for assessment of post-cardiac arrest neurological recovery under hypothermia in rats.

Neurological complications after cardiac arrest (CA) can be fatal. Although hypothermia has been shown to be beneficial, understanding the mechanism and establishing neurological outcomes remains challenging because effects of CA and hypothermia are not well characterized. This paper aims to analyze EEG (and the alpha-rhythms) using multiscale entropy (MSE) to demonstrate the ability of MSE in tracking changes due to hypothermia and compare MSE during early recovery with long-term neurological examinations.

Detection of repolarization alternans with an implantable cardioverter defibrillator lead in a porcine model.

Mechanistic links have been suggested between repolarization alternans (RPA) and the onset of ventricular tachycardia (VT) and/or fibrillation. Endocardial detection of RPA may, therefore, be an important step in future device-based treatments of arrhythmias. Here, we investigate if RPA could be detected during acute ischemia using an implantable cardioverter defibrillator (ICD) lead (tip to distal coil) located in the right ventricular apex.

Dynamics of stick-slip in peeling of an adhesive tape.

We investigate the dynamics of peeling of an adhesive tape subjected to a constant pull speed. We derive the equations of motion for the angular speed of the roller tape, the peel angle and the pull force used in earlier investigations using a Lagrangian. Due to the constraint between the pull force, peel angle and the peel force, it falls into the category of differential-algebraic equations requiring an appropriate algorithm for its numerical solution.