• Home
  • Leslie David Montgomery
Leslie David Montgomery

Leslie David Montgomery
LDM Associates

Ph.D. UCLA Eng.

About

157
Publications
15,955
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
2,073
Citations
Citations since 2016
34 Research Items
731 Citations
2016201720182019202020212022020406080100120
2016201720182019202020212022020406080100120
2016201720182019202020212022020406080100120
2016201720182019202020212022020406080100120
Education
June 2008 - June 2010
University of California, Santa Cruz
Field of study
  • Regulatory Affairs
August 1996 - June 1998
College of Notre Dame
Field of study
  • Systems Management
August 1964 - June 1972
University of California, Los Angeles
Field of study
  • Human Factors, Eng.

Publications

Publications (157)
Article
Full-text available
The following case study demonstrates that the effectiveness of Deep Tissue Massage (DTM) can be monitored in real time with bioimpedance. DTM techniques are used as a medical treatment to help reduce swelling of the calves of congestive heart failure patients. Bioimpedance monitoring shows immediately how fluid is redistributed within the intravas...
Article
Full-text available
Mathematical models that describe human thermoregulatory responses provide valuable information that can be used to prevent thermal injuries (e.g., heat or cold related), for training or planning purposes, and for an array of simulation activities such as analyzing after actions assessments. This paper focuses on the structure and mathematical basi...
Conference Paper
Full-text available
Brain EEG adctivity and fatgue
Article
Full-text available
Positive end-expiratory pressure (PEEP) is a respiratory/ventilation procedure that is used to maintain or improve breathing in clinical and experimental cases that exhibit impaired lung function. Body fluid shift movement is not monitored during PEEP application in intensive care units (ICU), which would be interesting specifically in hypotensive...
Article
Full-text available
1 LDM Associates, США 2 ДУ «Інститут урології НАМН України» 3 Національний технічний університет України «Київський політехнічний інститут імені Ігоря Сікорського» У статті наведено математичну модель терморегуляції людини у теплій воді і результати впливу теплої води на людину в умовах спокою та фізичного навантаження. Розглянуто діапазон зануренн...
Article
Full-text available
Background. This paper describes the mathematical model for human thermoregulation in warm water and demonstrates results for impact of warm water immersion in man during resting conditions and exercises. The purpose of the work is to describe a mathematical model of human thermoregulation in warm water and demonstrate the effects of immersion in w...
Article
Full-text available
Nonhuman primates are often used to investigate physiologic processes that occur in man during aerospace/cardiovascular orthostatic research. Few studies have compared nonhuman primates and man under identical test conditions to assess the degree of similarity between the two species. Impedance plethysmography was used to measure calf, thigh, pelvi...
Article
Full-text available
Purpose We compared the accuracy and design of two thermoregulatory models, the US Army's empirically designed Heat Strain Decision Aid (HSDA) and the rationally based Health Risk Prediction (HRP) for predicting human thermal responses during exercise in hot and humid conditions and wearing chemical protective clothing. Methods Accuracy of the HSD...
Article
Full-text available
The bioimpedance spectroscopic (BIS) analytical algorithm described in this report allows for the non-invasive measurement of intravascular, interstitial, and intracellular volume changes during various fluid management procedures. The purpose of this study was to test clinical use feasibility and to demonstrate the validity of the BIS algorithm in...
Article
Full-text available
Introduction The aim of this paper is to describe and demonstrate how a new bioimpedance analytical procedure can be used to monitor cellular hydration of End Stage Renal Disease (ESRD) patients during hemodialysis (HD). Methods A tetra-polar bioimpedance spectroscope (BIS), (UFI Inc., Morro Bay, CA), was used to measure the tissue resistance and r...
Article
Full-text available
Sorry - It will not copy. This article is about measuring segmental intracellular/intravscular volumes in humans during 90 min head down tilt at 6 degrees.
Article
Full-text available
INTRODUCTION This research employs a new EEG methodology to pursue two objectives. The first is to produce quantitative data that show how reading performance relates to a theoretical model of cortical processing of reading-related information. The second is to show that EEG can be used to classify reading disabled as well as normal readers along a...
Article
Full-text available
Nineteen MS patients‘ changes in cognitive performance test scores following a controlled period of head and torso cooling revealed improvement for most of the sample, but not for all, and a few actually performed worse. EEG visual evoked responses, in the form of scalp charge density time integrals revealed an inverse relationship betwee n the deg...
Article
Full-text available
Nonhuman primates are often used in biomedical research and to investigate physiologic processes that occur in man. Impedance plethysmography was used to measure calf, thigh, pelvic, abdominal, and thoracic volume changes in ten Rhesus and eight squirrel monkeys during five-minute exposures to HUT and HDT at angles of 5, 10, and 20 degrees. Calf, r...
Article
Full-text available
This paper describes a new combined impedance plethysmographic (IPG) and electrical bioimpedance spectroscopic (BIS) instrument and software that will allow noninvasive real-time measurement of segmental blood flow, intracellular, interstitial, and intravascular volume changes during various fluid management procedures. The impedance device can be...
Article
Full-text available
Introduction: End-staged renal disease (ESRD) patients may be dialyzed under both chronic and/or acute conditions. No information was found in the literature regarding the intracellular, interstitial and intravascular volume changes that take place under both chronic and acute dialysis. Aim: To measure the volume changes of the intracellular (Vc),...
Article
Full-text available
Abstarct Neuromonitoring is performed to prevent further (secondary) brain damage by detecting low brain blood flow following a head injury, stroke or neurosurgery. This comparative neuromonitoring study is part of an ongoing investigation of brain bioimpedance (rheoencephalography-REG) as a measuring modality for use in both civilian and military...
Conference Paper
Full-text available
Background. Water temperature is a key consideration for swimmers` safety during competition. Besides mandatory regulations, there is generally no advice given regarding the wearing of wetsuits. Aim. This study focuses on predictive modeling of the physiological responses of competitive swimmers under challenging water temperatures as a function o...
Article
Full-text available
This paper describes how ERP energy density analysis and marginal cost-benefit analysis were combined to interpret the results of an investigation of mental performance. Eleven subjects competed in performing computer-generated mental arithmetic tasks over a period lasting, in some cases, 2.5 hours. Assuming that brain resources are dynamically all...
Article
Full-text available
This paper describes a new combined impedance plethysmographic (IPG) and electrical bioimpedance spectroscopic (BIS) instrument and software that allows noninvasive real-time measurement of segmental blood flow and changes in intracellular, interstitial, and intravascular volumes during various fluid management procedures. The impedance device can...
Thesis
Full-text available
This capstone report outlines the development of neurophysiological procedures to monitor the enhanced cognitive processing by multiple sclerosis patients following short term body cooling therapy. The approach included use of topographic electroencephalographic (TEEG) measures of cerebral function, a visual discrimination task administered by comp...
Article
Full-text available
Introduction The aim of this paper is to describe and demonstrate how a new bioimpedance analytical procedure can be used to monitor cellular hydration of End Stage Renal Disease (ESRD) patients during hemodialysis (HD). Methods A tetra‐polar bioimpedance spectroscope (BIS), (UFI Inc., Morro Bay, CA), was used to measure the tissue resistance and r...
Conference Paper
Full-text available
Introduction Cold water is a dangerous risk factor for swimmers in spite of the intensive physical load they perform. Wetsuits are used to avoid possible cooling of sportsmen in some competitions [1]. The typical fabric used for a wetsuit is neoprene. A neoprene wetsuit effectively prevents swimmers from hypothermia in cold water. It is important t...
Research
Full-text available
This is a final contract report written by Wayne A. Gerth which includes several conference presentations co-authored by L. D. Montgomery, Y.C. Wu and D. C. Sasser. They describe the use of bioimpedance spectroscopy to quantify fluid compartment volumes under different experimental conditions.
Data
This presentation was given to the faculty of New York Medical College to provide an overview of the use of bioimpedance to quantify segmental responses to various experimental/medical conditions.
Research
Full-text available
An Engineering PhD dissertation form UCLA 1972
Research
Full-text available
This manual contains the instructions to analyze fixed frequency bioimpedance data to obtain hemodynamic and circulatory parameters.
Research
This paper describes the calf, thigh, and torso fluid compartment volumes and hemodynamic responses to short term -6 Deg. head down tilt in humans. Impedance spectroscopy and fixed frequency impedance plethysmography was used together to better define the physiologic responses to HDT.
Article
Full-text available
Mental fatigue was associated with increased power in frontal theta (θ) and parietal alpha (α) EEG rhythms. A statistical classifier can use these effects to model EEG-fatigue relationships accurately. Participants (n = 22) solved math problems on a computer until either they felt exhausted or 3 h had elapsed. Pre-and post-task mood scales showed t...
Article
Full-text available
The bioimpedance spectroscopic (BIS) analytical algorithm described in this report allows for the non-invasive measurement of intravascular, interstitial, and intracellular volume changes during various fluid management procedures. The purpose of this study was to test clinical use feasibility and to demonstrate the validity of the BIS algorithm in...
Article
Full-text available
The bioimpedance spectroscopic (BIS) analytical algorithm described in this report allows for the non-invasive measurement of intravascular, interstitial, and intracellular volume changes during various fluid management procedures. The purpose of this study was to test clinical use feasibility and to demonstrate the validity of the BIS algorithm in...
Conference Paper
Electrical impedance spectroscopic (EIS) technique is a novel method to non-invasively measure the fluid volume in the Vc, Vi, and Vb compartments in humans. The aim is to use EIS technology to measure Vc, Vi, and Vb volume change during HD in end-stage renal disease (ESRD) patients in the outpatient or chronic unit (CU) and in the inpatient or acu...
Conference Paper
Full-text available
A new electrical impedance spectroscopic (EIS) procedure has been developed that permits the non-invasive measurement of the volume changes in the three separate fluid spaces or compartments (intravascular, interstitial, and intracellular) of a body segment in humans.
Conference Paper
Full-text available
Monitoring compartment volumes using EIS
Article
Full-text available
Findings regarding the influence hemodynamic factors, such as increased arterial blood flow or venous abnormalities, on breast cancer treatment-related lymphedema are mixed. The purpose of this study was to compare segmental arterial blood flow, venous blood return, and blood volumes between breast cancer survivors with treatment-related lymphedema...
Article
Full-text available
Upright posture and lower body negative pressure (LBNP) both induce reductions in central blood volume. However, regional circulatory responses to postural changes and LBNP may differ. Therefore, we studied regional blood flow and blood volume changes in 10 healthy subjects undergoing graded lower-body negative pressure (-10 to -50 mmHg) and 8 subj...
Article
Full-text available
Lymphedema is a problem for breast cancer survivors. The proliferation of limb measurement techniques makes it difficult to know how best to measure an at-risk limb. Using a sample of healthy volunteers and individuals with lymphedema, this study: 1) examined the relationship between more commonly used circumferential limb measurement methods and n...
Article
Full-text available
Increased blood pressure (BP) and heart rate during exercise characterizes the exercise pressor reflex. When evoked by static handgrip, mechanoreceptors and metaboreceptors produce regional changes in blood volume and blood flow, which are incompletely characterized in humans. We studied 16 healthy subjects aged 20-27 yr using segmental impedance p...
Article
Full-text available
Previous investigations have allowed for stratification of patients with postural tachycardia syndrome (POTS) on the basis of peripheral blood flow. One such subset, comprising "normal-flow POTS" patients, is characterized by normal peripheral resistance and blood volume in the supine position but thoracic hypovolemia and splanchnic blood pooling i...
Article
Full-text available
Prior work demonstrated dependence of the change in blood pressure during the Valsalva maneuver (VM) on the extent of thoracic hypovolemia and splanchnic hypervolemia. Thoracic hypovolemia and splanchnic hypervolemia characterize certain patients with postural tachycardia syndrome (POTS) during orthostatic stress. These patients also experience abn...
Article
Full-text available
Six tourniquets designed for combat application were tested for their ease of use and ability to occlude arterial blood flow to the upper arms and thighs in a repeated measures design. To simulate nighttime desert combat conditions, subjects completed an exercise routine while the tourniquet was immersed in a blood analog solution and rolled in san...
Article
Full-text available
Recent studies have indicated that plantar-based vibration may be an effective approach for the prevention and treatment of osteoporosis. We addressed the hypothesis of whether the plantar vibration operated by way of the skeletal muscle pump, resulting in enhanced blood and fluid flow to the lower body. We combined plantar stimulation with upright...
Article
Full-text available
The Valsalva maneuver is frequently used to test autonomic function. Previous work demonstrated that the blood pressure decrease during the Valsalva maneuver relates to thoracic hypovolemia, which may preclude pressure recovery during phase II, even with normal resting peripheral vasoconstriction. We hypothesized that increased regional blood volum...
Article
Full-text available
We measured multichannel EEG spectra during a continuous mental arithmetic task and created statistical learning models of cognitive fatigue for single subjects. Sixteen subjects (4 F, 18-38 y) viewed 4-digit problems on a computer, solved the problems, and pressed keys to respond (inter-trial interval = 1 s). Subjects performed until either they f...
Article
Full-text available
The mechanisms of simple faint remain elusive. We propose that postural fainting is related to excessive thoracic hypovolemia and splanchnic hypervolemia during orthostasis compared with healthy subjects. We studied 34 patients 12 to 22 years old referred for multiple episodes of postural faint and 11 healthy subjects. Subjects were studied in the...
Article
Full-text available
Variants of postural tachycardia syndrome (POTS) are associated with increased ["high-flow" POTS (HFP)], decreased ["low-flow" POTS (LFP)], and normal ["normal-flow" POTS (NFP)] blood flow measured in the lower extremities while subjects were in the supine position. We propose that postural tachycardia is related to thoracic hypovolemia during orth...
Article
Full-text available
The Valsalva maneuver (VM) is frequently used to test autonomic function. However, the VM is also affected by changes in blood volume and blood volume redistribution. We hypothesized that even a standardized VM may produce a wide range of thoracic blood volume shifts. Larger blood volume shifts in some normovolemic individuals may be sufficient to...
Article
Full-text available
We analyzed EEG and ERPs in a fatiguing mental task and created statistical models for single subjects. Seventeen subjects (4 F, 18-38 y) viewed 4-digit problems (e.g., 3+5-2+7=15) on a computer, solved the problems, and pressed keys to respond (intertrial interval = 1 s). Subjects performed until either they felt exhausted or three hours had elaps...
Article
Full-text available
Standing translocates thoracic blood volume into the dependent body. The skeletal muscle pump participates in preventing orthostatic intolerance by enhancing venous return. We investigated the hypothesis that skeletal muscle pump function is impaired in postural tachycardia (POTS) associated with low calf blood flow (low-flow POTS) and depends in g...
Article
Full-text available
Postural tachycardia syndrome (POTS) is defined by orthostatic intolerance associated with abnormal upright tachycardia. Some patients have defective peripheral vasoconstriction and increased calf blood flow. Others have increased peripheral arterial resistance and decreased blood flow. In 14 POTS patients (13-19 yr) evenly subdivided among low-flo...
Article
Full-text available
Cooling demyelinated nerves can reduce conduction block, potentially improving symptoms of MS. The therapeutic effects of cooling in patients with MS have not been convincingly demonstrated because prior studies were limited by uncontrolled designs, unblinded evaluations, reliance on subjective outcome measures, and small sample sizes. To determine...
Article
Full-text available
In spite of the known importance of cerebral blood flow (CBF) monitoring for aviation, spaceflight, military and emergency medicine, and neurosurgical intra- and postoperative monitoring, there is no standard noninvasive technique for continuous CBF monitoring. One potential method for this purpose is the electrical impedance technique, called rheo...
Conference Paper
Full-text available
To develop practical, easily applied, measures of cerebral activity that can be used under operational conditions in human factors research:- Topographic electroencephalography, Rheoencephalography and Electrophysiology
Conference Paper
Full-text available
We report here results of electrical impedance validation studies performed in vitro (piston and peristaltic pump) and in vivo (rabbit and human) to measure peripheral blood flow by analysis of electrical impedance pulse waves. The measurements were compared to those derived by measuring hydrostatic pressure, electromagnetic flow, noninvasive blood...
Conference Paper
Full-text available
In today's workplace it is not uncommon for a worker to be using several computer/information displays at the same time, or to use an information display throughout a long and static work cycle. Multi-tasking, intense work load, a sub-optimal display, stress, fatigue, and distraction -- any one of these can eventually lead to performance errors. It...
Article
Full-text available
The objective of this study was to compare the responses of multiple sclerosis (MS) patients to short-term cooling therapy using three different vest configurations. Each garment was used to cool 13 male and 13 female MS subjects (31-67 yr). Oral and right and left ear temperatures were logged manually every 5 min. Arm, leg, chest, and rectal tempe...
Article
semenvatting Physiological and thermal responses of male and female patients with multiple sclerosis to head and neck cooling [American Journal of Physical Medicine and Rehabilitation 1999;78;5:447-56]
Conference Paper
Full-text available
This pilot study compared three commercially available office chairs in terms of subjects' hemodynamics, core temperatures, preferences, mental workload, and task performance. With only five subjects, the trends did not converge; rather, one chair resulted in better hemodynamics over time, while another seemed to maintain stable core temperatures a...
Article
Mental exhaustion often poses a serious risk, even when performance is not apparently degraded. When such fatigue is associated with sustained performance of a single type of cognitive task it may be related to the metabolic energy required for sustained activation of cortical fields specialized for that task. The objective of this study was to ada...
Article
Personal thermoregulatory systems which provide chest cooling are used in the industrial and aerospace environments to alleviate thermal stress. However, little information is available regarding the physiologic and circulatory changes produced by routine operation of these systems. The objectives of this study were to document and compare the subj...