| A Psychophysiologic Study of Weakening Traumatic Combat Memories with Post-Reactivation Propranolol |
Jun-2009 |
6 pages |
| Authors:
Roger K Pitman; GENERAL HOSPITAL CORP BOSTON MA
|
 | The objective of this project is to test whether the beta-adrenergic blocker propranolol, given following combat memory reactivation, results in a significantly greater weakening of traumatic memories than propranolol alone, supporting the proposition that this weakening is due to pharmacological blockade of memory reconsolidation, rather than nonspecific actions of propranolol. We hypothesize that subjects who undergo script preparation for the combat event(s) that caused their PTSD, followed by (post-reactivation) propranolol, ... |
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| Neck Muscle Fatigue Resulting from Prolonged Wear of Weighted Helmets under High G Acceleration |
01-Jun-2008 |
34 pages |
| Authors:
Chuck Goodyear; Edward S Eveland; Bob Esken; Nick Shouse; Matt Kane; HUMAN EFFECTIVENESS DIRECTORATE WRIGHT-PATTERSON AFB OH AIRCREW PROTECTION BRANCH
|
| In search of guidelines for designing helmet-mounted systems without adding risk for additional pilot neck pain or injury, RHPG collaborated with the panoramic night vision goggle (PNVG) program office to begin this research. Neck muscles become fatigued as they work to stabilize the additional weight of helmet systems. The center of gravity (CG) of each individual helmet configuration varies according to the accessories attached. Neck strength measurements before and after ... |
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| Wavelet-Based Signal Processing for Monitoring Discomfort and Fatigue |
Jun-2008 |
106 pages |
| Authors:
Cristhian Von Potes; Ricardo Borries; Cristiano J Miosso; TEXAS UNIV AT EL PASO
|
| Muscle fatigue involves both a decrease in the frequency and increase in the amplitude of a surface electromyographic (SEMG) signal. Muscle fatigue is also related to a decrease of the force impeding to reach the same initial level of the maximum voluntary contraction (MVC). To determine indices of muscle fatigue, a method is proposed to estimate both the instantaneous frequency (IF) and the instantaneous amplitude (IA) by decomposing the SEMG ... |
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| Integrated Sensor Systems for UAS |
01-Apr-2008 |
14 pages |
| Authors:
Mark C Patterson; Anthony Brescia; ADVANCED CERAMICS RESEARCH TUCSON AZ
|
| The miniaturization of sensors has in recent years led to the ability to provide multiple sensor operations from a single Unmanned Aircraft System (UAS) platform. Multiple UAS platforms can be synchronized to link devices from separate UAS platforms thus proving a powerful capability for data collection, while opening up interesting opportunities in the way data is retrieved and used. A range of new sensors being investigated will be discussed with ... |
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| Neck Muscle Fatigue with Helmet-Mounted Systems |
SEP 2006 |
8 pages |
| Authors:
Edward S. Eveland; Joseph A. Pellettiere; HUMAN EFFECTIVENESS DIRECTORATE WRIGHT-PATTERSON AFB OH AIRCREW PROTECTION BRANCH
|
| Helmet-mounted systems (HMS) allow aircrew to perform more efficiently in poor conditions. Optics allow improved visibility, night vision, helmet-mounted displays, and targeting capability. The cost to use them in high performance aircraft is unknown. Test flights were made with pilots wearing HMS and neck muscles were evaluated. Objectives were to test the functionality of the helmet-mounted devices and to determine the impact on pilots using them during high G acceleration. ... |
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| Human Neck Response during Vertical Impact with Variable Weighted Helmets |
SEP 2006 |
85 pages |
| Authors:
Erica J. Doczy; Joseph A. Pellettiere; Hilary L. Gallagher; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH HUMAN EFFECTIVENESS DIRECTORATE
|
| Helmet-mounted systems, such as night vision goggles and helmet-mounted displays, are designed to enhance pilot performance; however, they may also affect pilot safety during ejection due to the change in helmet inertial properties. The weight of a helmet, along with a pilot's bracing ability, can affect the human response and potential for neck injury during impact. A useful tool for investigating the mechanics of bracing and the relationships to helmet ... |
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| Neck Muscle Activation Levels During Frontal Impacts |
SEP 2004 |
10 pages |
| Authors:
Joseph Pellettiere; Mary A. Sanders; Erica Doczy; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH HUMAN EFFECTIVENESS DIRECTORATE
|
| Helmet-mounted systems, such as night vision goggles and helmet-mounted displays, are designed to enhance pilot performance; however, they may also affect pilot safety during ejection due to the change in helmet inertial properties. The effects of variable helmet weight and bracing ability on subject response during impact are unknown. Electromyogram (EMG) is a useful tool to investigate the mechanics of bracing and the relationships to helmet weight and impact acceleration. ... |
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| Neural Network Approaches to the Processing of Experimental Electro-Myographic Data from Non-Invasive Sensors |
19 NOV 2003 |
13 pages |
| Authors:
Francesco C. Morabito; Maurizio Campolo; MEDITERRANEA UNIV CALABRIA (ITALY) DIPDI INFORMATICA MATEMATICA ELETTRONICAE TRASPORTI
|
| Learning theories and algorithms for both supervised and unsupervised Neural Networks (NNs) have already been accepted as relevant tools to cope with difficult problems based on the processing of experimental electromagnetic data. These kinds of problems are typically formulated as inverse problems. In this paper, in particular, the electrical signals under investigations derive from experimental electromyogram interference patterns measured on human subjects by means of non-invasive sensors (surface ElectroMyoGraphic, sEMG, ... |
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| Use of Biofeedback in Occupational Risk Prevention |
14 MAY 2003 |
|
| Authors:
Jan Seghers; Hans Ponnet; Arthur Spaepen; KATHOLIEKE UNIV LEUVEN (BELGIUM) LAB FOR ERGONOMICS AND OCCUPATIONAL BIOMECHANICS
|
 | Surface electrode EMG signals can be used to estimate muscle activity and even fatigue. In the present study surface electromyography (sEMG) is used as a biofeedback training tool. The purpose of this pilot study is to investigate the usability of this method in real working environments and to study the effect of biofeedback on the neck-shoulder muscle activity. Five female subjects (mean age : 42 years; mean height: 1.63 m; ... |
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| European Community Projects on Surface Electromyography |
25 OCT 2001 |
|
| Authors:
R. Merletti; H. Hermens; R. Kadefors; POLITECNICO DI TORINO (ITALY) DIPT DI ELETTRONICA
|
| Three European Projects dealing with Surface Electromyography (SEMG) are presented. Surface EMG for Non-invasive Assessment of Muscles (SENIAM, 1996- 2000) produced a set of European guidelines concerning EMG sensors, their positioning criteria, EMG processing, modeling a ad information extraction. Prevention of muscle disorders in operation Of computer input devices (PROCID, 1998-2001) dealt with wire and surface EMG and provided insight in muscular disorders in computer users. Neuromuscular assessment in the ... |
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| Quantization of Motor Activity into Primitives and Time-Frequency Atoms Using Independent Component Analysis and Matching Pursuit Algorithms |
25 OCT 2001 |
|
| Authors:
Simon F. Giszter; MEDICAL COLL OF PENNSYLVANIA PHILADELPHIA DEPT OF ANATOMY AND NEUROBIOLOGY
|
| It has been proposed that the segmental spinal nervous system may organize movement using a collection of force-field primitives. The temporal organization of primitives has not been examined in detail. Recent data examining muscle activity underlying corrections of motor patterns suggested that primitives might be recruited into motor programs as waveforms with a constant duration. Here we test the idea that each primitive or premotor drive comprising part of the ... |
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| Three-Dimensional Model of a Muscle and Simulation of its Surface EMG |
25 OCT 2001 |
|
| Authors:
M. A. Schnetzer; D. G. Ruegg; R. Baltensperger; J. P. Gabriel; FRIBOURG UNIV (SWITZERLAND)
|
| The aim of this paper was to present a spatial model of a muscle including all its motor units (MU) and a simulation of its surface EMG. The simulations are part of a larger model including in addition the input system to the motoneuronal pool, the motoneuronal pool itself and the force generating mechanism. The muscle and the MU territories are represented by elliptic cylinders. Two algorithms are presented to ... |
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| A Mechanically Flexible, Battery-Powered, Differential Electrode Unit for Electrophysiological Recordings |
25 OCT 2001 |
|
| Authors:
S. Martel; L. Jones; I. Hunter; MASSACHUSETTS INST OF TECH CAMBRIDGE INSTRUMENTATION LAB
|
| This paper describes a new type of micro-powered electrode configuration. The circuit consists of an instrumentation amplifier and a special AC coupling configuration that maintains a high CMRR with a gain of a 1000. All electronics, including two lithium batteries, are mounted on a flexible circuit board (FPC). The single FPC has a special shape that allows differential recording at various distances between the electrodes. The whole circuit is typically ... |
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| Principal Components of Recurrence Quantification Analysis of EMG |
25 OCT 2001 |
|
| Authors:
David T. Mewett; Karen J. Reynolds; Homer Nazeran; FLINDERS UNIV OF SOUTH AUSTRALIA ADELAIDE SCHOOL OF INFORMATICS AND ENGINEERING
|
| A nonlinear dynamical signal analysis technique, recurrence quantification analysis (RQA), was applied to surface electromyograms (EMG) recorded during a series of isometric contractions. None of the ten RQA features calculated adequately related the EMG to the force level so principal components analysis was applied to combine these features into a lower number of variables. Linear regression of the first principal component gave similar lines for each subject. However, the error ... |
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| A Biologically Inspired Neural Network Composed of Dissimilar Single Neuron Models |
25 OCT 2001 |
|
| Authors:
P. Poirazi; C. C. Neocleous; C. S. Pattichis; C. N. Schizas; CYPRUS UNIV NICOSIA DEPT OF COMPUTER SCIENCE
|
| A multilayer neural network has been developed that consists of slabs of single neuron models. Each slab is composed of a single type of neurons, which differs between the slabs. The network was trained using a biologically inspired, Hebbian-like, learning rule on EMG data and good training/testing classification performance was obtained. It was shown that the biologically inspired network, the novel architecture of which is derived from the functionally distinct ... |
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| Feasibility of EMG-Based Control of Shoulder Muscle FNS Via Artificial Neural Network |
25 OCT 2001 |
|
| Authors:
R. F. Kirsch; P. P. Parikh; A. M. Acosta; F. van der Helm; CASE WESTERN RESERVE UNIV CLEVELAND OHDEPT OF BIOMEDICAL ENGINEERING
|
| We investigated the potential use of EMG recordings from voluntary shoulder muscles in individuals with C5 spinal cord injury to automatically control the stimulation to paralyzed shoulder muscles in a task-appropriate manner. A musculoskeletal model of the human shoulder and elbow was modified to have maximum muscle forces appropriate for C5 spinal cord injury, including completely and partially paralyzed muscles. Inverse model simulations generated muscle activation levels that were used ... |
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| Recruitment and Decruitment of Motor Units Activities of M. Biceps Brachii During Isovelocity Movements |
25 OCT 2001 |
|
| Authors:
Ryuhei Okuno; Kenzo Akazawa; OSAKA UNIV (JAPAN) GRADUATE SCHOOL OF ENGINEERING
|
| The purpose of this study is to investigate behaviors of motor units of m. biceps brachii (biceps short head muscle) during flexion movements in wide range of elbow joint angle. In this study, eight surface electromyograms(EMGs) were measured during flexion movements at constant angular velocity (isovelocity) and against constant torque in wide range (from 0 DEG to 120 DEG) of elbow joint angle with a surface electrode array. We identified ... |
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| Interhemispheric Differences of Hand Motor Cortex Organization: MEG-EMG Cortico-Muscolar Coherence |
25 OCT 2001 |
|
| Authors:
Camillo Porcaro; Franca Tecchio; Filippo Zappasodi; Carlo Salustri; Matilde Ercolani; CONSIGLIO NAZIONALE DELLE RICERCHE ROME(ITALY)
|
| Corticomuscular coherence between cerebral cortical rhythms and the surface electromyography (EMG) has been observed both through electrocorticogram and by electroencephalographic (EEG) and magnetoencephalographic (MEG) recordings. Corticomuscular coherence is a tool for identification and characterization of cortical districts controlling a particular body district, based on amplitude and frequency selection. MEG recordings of parietal contralateral cerebral activity, and muscular activity from right and left extensor comunis digitorum (ECD) have been studied in ... |
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| Motor Unit Action Potentials as a Source of Noise in the Non-Invasive Detection of Fibrillation Potentials |
25 OCT 2001 |
|
| Authors:
Steven Keller; Shai Gozani; MASSACHUSETTS INST OF TECH CAMBRIDGE HARVARD-MIT DIV OF HEALTH SCIENCES AND TECHNOLOGY
|
| Denervated muscle fibers produce spontaneous depolarizations termed fibrillation potentials. These potentials are an indicator of neuromuscular pathology and are detected by inserting a needle electrode into the muscle of interest to detect the time-based signal. A proposed noninvasive method measures the spectral energy corresponding to increased spontaneous muscle activity. This paper exams the impact of normal muscle activity on such a method through the use of a computer model of ... |
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| Upper Extremity Motion Assessment in Adult Ischemic Stroke Patients: A 3-D Kinematic Model |
25 OCT 2001 |
|
| Authors:
J. Van Bogart; J. McGuire; G. F. Harris; MEDICAL COLL OF WISCONSIN MILWAUKEE
|
| As part of a larger evaluative study of the effects of botulinum toxin type A (BTA) in ischemic stroke patients, a kinematic model of the trunk and upper extremities (UE) has been developed, The 3-D model provides a comprehensive method of assessing UE motion during performance tasks including exercises in reaching, grasping, and releasing, The 17-marker system tracks UE motion at a rate of 120 SPS with 7 infrared CCD ... |
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| Upper Limb-Hand 3D Display System for Biomimetic Myoelectric Hand Simulator |
25 OCT 2001 |
|
| Authors:
Gonzalo G. Jimenez; Okuno Ryuhei; Kenzo Akazawa; OSAKA UNIV (JAPAN) GRADUATE SCHOOL OF ENGINEERING
|
| A graphics system displaying both upper limb posture and opening- closing of a prosthetic hand was developed for realtime operation of our biomimetic myoelectric hand simulator, Posture of the upper limb was determined by 3D position of shoulder, elbow and wrist, which were detected with Optotrack. Finger angle of the hand was given by the simulator, which receive the surface myoelectric signal (EMGs) of both flexor and extensor muscles of ... |
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| Evaluation of Walkers for Elderly People |
25 OCT 2001 |
|
| Authors:
T. Tamura; M. Sekine; H. Kuno; M. Fujie; A. Mori; NATIONAL INST FOR LONGEVITY SCIENCES AICHI (JAPAN)
|
| The aim of this study was to evaluate three types of walkers for elderly people, Four elderly patients participated in the study. The experiments were performed using three walkers: a familiar conventional folding walker, a caster walker and a power-assisted walker, We evaluated walking speed, body acceleration and an electromyogram of the gastrocnemius during use of each walker, The results indicated that walkers should be selected according to the patient's ... |
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| Reflex Responses to Ligament Loading: Implications for Knee Joint Stability |
25 OCT 2001 |
|
| Authors:
Y. Y. Dhaher; A. D. Tsoumanis; W. Z. Rymer; REHABILITATION INST OF CHICAGO IL
|
| To assess the neuromuscular reflex responses to loading of knee ligaments, we applied an abducting positional deflection to the fully extended knee using a servomotor, and recorded EMG activity in preactivated quadriceps and hamstrings muscles with surface electrodes. To establish that the reflex response elicited by the perturbation was not simply a form of muscle stretch response, a tendon tap was applied to the muscles at the same setting and ... |
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| Reduction of Skin Impedance by the Improvement of the Blood Circulation |
25 OCT 2001 |
|
| Authors:
J. G. Bau; Y. Y. Wang; W. K. Wang; NATIONAL TAIWAN UNIV TAIPEI DEPT OF PHYSICS
|
| When biopotentials are recorded from the surface of the skin, skin impedance will usually influence the measurement. In this study, skin impedance was minimized by improving blood circulation. The investigators found that skin impedance can be reduced by more than 50% if the skin is soaked in warm water for 5 minutes. This method can be applied to all situations in which surface electrodes such as EKG, EEG, and EMG ... |
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| Selective Stimulation of the Hypoglossal Nerve with a Multi-Contact Cuff Electrode |
25 OCT 2001 |
|
| Authors:
P. B. Yoo; D. M. Durand; CASE WESTERN RESERVE UNIV CLEVELAND OHDEPT OF BIOMEDICAL ENGINEERING
|
| The feasibility of selectively stimulating the hypoglossal nerve (XII) with a multi-contact flat-interface-nerve -electrode (FIE) was investigated for the potential application of treating obstructive sleep apnea (OSA) The main trunk of the XII was stimulated with monophasic cathodic pulses, while the elicited electroneurographic (ENG) and electromyographic (EMG) signals were recorded, Selective fascicular stimulation of the XII was achieved but with certain limitations: branches 1 and 2 could not be independently ... |
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| Reflex and Non-Reflex Torque Responses to Stretch of the Human Knee Extensors |
25 OCT 2001 |
|
| Authors:
N. Mrachacz-Kersting; T. Sinkjaer; AALBORG UNIV (DENMARK) CENTER FOR SENSORY-MOTOR INTERACTION
|
| Reflex responses to unexpected stretches are well documented for a range of muscles in both animal and human. Moreover, investigations of their possible functional significance, has revealed that reflexes can contribute substantially to the overall stiffness of a joint. Unfortunately due to obvious technical limitations, only the muscles spanning the human ankle joint have been investigated in the lower extremity in the past. This study implements a unique hydraulic actuator ... |
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| Comparison of Stretch Reflex Torques in Ankle Dorsiflexors and Plantarflexors |
25 OCT 2001 |
|
| Authors:
J. Y. Tung; R. E. Kearney; L. Galiana; MCGILL UNIV MONTREAL (QUEBEC) DEPT OF BIOMEDICAL ENGINEERING
|
| This study compared the intrinsic and reflex torques generated in response to position perturbations in tibialis anterior (TA) and gastrocnemius (CS) ankle muscles, Pulse, step, and a combination of random perturbation and step inputs were used to identify the reflex and intrinsic contributions to the measured torque, TA reflex torques were very small whereas CS reflex torques were substantial. |
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| Neck Muscle Response to Changes in Helmet Loading Under +Gz Acceleration - Gender Differences |
JUN 2001 |
36 pages |
| Authors:
Edward S. Eveland; Chuck Goodyear; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH HUMAN EFFECTIVENESS DIRECTORATE
|
| Helmet-mounted devices (HMDs) can provide valuable assistance to the pilots of high performance aircraft. They allow operations to be accomplished in poor conditions and can improve effectiveness. However, each device changes the helmet configuration adding more weight and can change the center of gravity of the helmet. These factors are often implicated in reports of acute neck pain and cervical vertebral damage. Females, in particular, may be at risk for ... |
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| Incidence and Psychophysiology of Post-Traumatic Stress Disorder in Breast Cancer Victims and Witnesses |
OCT 1999 |
16 pages |
| Authors:
Roger K. Pitman; HARVARD COLL CAMBRIDGE MA
|
| This study evaluated breast-cancer patients and their "witnesses" (significant others) for post-traumatic stress disorder (PTSD) related to the patient's breast cancer experience. Participants were interviewed by telephone with the PTSD Checklist (PCL), invited to come for a personal interview with the Clinician-Administered PTSD Scale (CAPS), and then invited for psychophysiologic testing. The estimated incidence of breast cancer-related PTSD during the approximately two years elapsed since tissue diagnosis was 24% (21/87) ... |
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| Effects of Head-Supported Devices on Female Aviators during Simulated Helicopter Missions |
MAY 1998 |
122 pages |
| Authors:
Nabih Alem; ARMY AEROMEDICAL RESEARCH LAB FORT RUCKER AL
|
| This report describes the work completed during the first project year of this research study. The objective of the study is to identify safe weight and location limits of head-supported devices worn by female aviators during simulated helicopter rides. The working hypothesis is that female pilots will tolerate some range of HSD weight moments beyond which their biomechanical and performance responses will deteriorate. The report ... |
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| The Effect of Hypoxia, Cold, and Exercise on Human Thermoregulation |
23 DEC 96 |
20 pages |
| Authors:
J. Reading; D. Roberts; J. Hodgdon; R. Pozos; NAVAL HEALTH RESEARCH CENTER SAN DIEGO CA
|
| U.S. Marine and Navy personnel may be at an increased risk for developing hypothermia when training at 2700 m. The objective of this study was to determine if exposure to moderate cold and decreased oxygen (O2) tension (15% O2 simulating 2700 m) reduces the ability of the human body to shiver and to maintain core and skin temperatures during moderate exercise. Eight male and two female U.S. Navy and Marine ... |
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| A Physiological and Biomechanical Evaluation of Commercial Load-Bearing Ensembles for the U.S. Marine Corps |
14 MAY 96 |
49 pages |
| Authors:
Donald E. Roberts; James E. Reading; Janine L. Daley; James A. Hodgdon; Robert S. Pozos; NAVAL HEALTH RESEARCH CENTER SAN DIEGO CA
|
| The purpose of this study was to evaluate 13 commercial load-bearing ensembles (LBE) in relation to the ALICE pack to determine the best load-to- individual interface for use by the U.S. Marine Corps. Each LBE was evaluated biomechanically (gait and electromyographically), physiologically (heart rate and oxygen uptake), and subjectively (perceived exertion and LBE preference). Subjects (n = 14) carried 100 lbs for 4 hr (50/10 walk/rest) at 2.5 mph and ... |
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| Muscle Activity and Fatigue during Push-ups Performed by Women: An Electromyographic and Videographic Analysis of Fifteen Muscles |
APR 1996 |
62 pages |
| Authors:
Michael D. Robinson; WALTER REED ARMY MEDICAL CENTER WASHINGTON DC
|
| This study sought to determine the primary muscles used by women during pushups and to establish differences in muscle firing patterns and utilization between elite and marginal performers Design: Cohort Analytic Study assessing differences in muscle activity and utilization during pushups between two groups of women at differing levels of ability. Participants : Sixty three women scoring in elite or marginal categories were enrolled. Main Outcome Measure: Video and intramuscular ... |
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| Load Carriage Using Packs: A Review of Physiological, Biomechanical and Medical Aspects |
96 |
|
| Authors:
Joseph Knapik; Everett Harman; Katy Reynolds; ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
|
| This paper reviews the. biomedical aspects of transporting loads in packs and offers suggestions for improving load-carriage capability. Locating the load mass as close as possible to the body center of gravity appears to result in the lowest energy cost when carrying a pack. Thus, the double pack (half the load on the front of the body and half the load on the back) has a lower energy cost than ... |
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| The Activity of High-Frequency Vibratory Sensitive Neurons in Monkey Primary Somatosensory Cortex during the Initiation of Vibratory and Visually Cued Hand Movements |
95 |
22 pages |
| Authors:
Michael A. Lebedev; Randall J. Nelson; TENNESSEE UNIV MEMPHIS DEPT OF ANATOMY AND NEUROBIOLOGY
|
| The activity of high-frequency vibratory sensitive (nFVS) neurons was recorded in monkey primary somatosensory cortex (SI) while animals performed wrist flexions and extensions in response to 27, 57 or 127 Hz palmar vibration or in response to visual stimuli serving as go-cues. HFVS neurons were distinguished by their best responsiveness to the highest frequency vibration (127 Hz) being better than to the lower frequencies. These neurons probably received input from ... |
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| Physiologic Instrumentation in the Naval Air Warfare Center Human-use Centrifuge to Determine the Effects of Cumulative +Gz on Cognitive Performance |
01 OCT 94 |
50 pages |
| Authors:
Estrella M. Forster; Jeffrey G. Morrison; Edward M. Hitchcock; Mark W. Scerbo; NAVAL AIR WARFARE CENTER AIRCRAFT DIV WARMINSTER PA
|
| A study to determine the effect of intermittent periods of positive acceleration (+Gz) on human physiology and cognitive performance was accomplished at the Naval Air Warfare Center (NAWO) human-use centrifuge. This report discusses the materials and methods utilized to obtain various physiologic measures during this study: electroencephalogram (EEG); electrooculogram (EOG); electromyogram (EMG); infrared plethysmography (lRP); electrocardiogram (ECG); and respiration rate (RM). The methods discussed herein are specific to the NAWO ... |
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| Effects of Shivering on Rifle Shooting Performance in U. S. Marines |
24 MAR 94 |
|
| Authors:
J. E. Reading; P. S. Kincaid; D. E. Roberts; R. L. Hesslink; R. S. Pozos; NAVAL HEALTH RESEARCH CENTER SAN DIEGO CA
|
| Exposure to cold has played a major role in compromising military operations for many years. Cold injuries such as frostbite and trench foot have plagued military personnel in this country since the American Revolution and were critical to military losses. The effects of cold exposure on exercise performance, nutrition, and physiological parameters have been extensively studied throughout the years. Shivering is defined as an increase in reflex, nonlocomotor muscular tone ... |
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| Thermoregulatory Effects of Atropine in the Cold Using a Hypotrichotic Rat Model |
NOV 1993 |
13 pages |
| Authors:
BrianJ. Gentile; Criag R. Johnson; Ralph P. Francesconi; Roger W. Hubbard; ARMY RESEARCH INST OF ENVIRONMENTAL MEDICINE NATICK MA
|
| The objectives of this research were to determine the effects of atropine on thermoregulation and peripheral vasodilation in the cold. A conscious, confined but unrestrained, hypotrichotic (Wistar-Furth, fuzzy) rat model was used. Electromyography (EMG) was utilized to assess the shivering response of the trapezius muscle. An EMG frequency band between 3 Hz and 1 kHz was rectified, then integrated for determination of a shivering index. Infrared thermography was used to ... |
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| Evaluation of Physiological and Psychological Impairment of Human Performance in Cold Stressed Subjects |
05 JUN 93 |
183 pages |
| Authors:
Lorentz E. Wittmers; Richard Hoffman; MINNESOTA UNIV DULUTH
|
| The effects of 2 shiver suppression techniques on performance of military relevant motor tasks, body heat conservation, and metabolic functions during cold exposure were investigated using a repeated measures MANOVA design. Nine male volunteers, 24.3 + or - 0.8 yr, were exposed for 3 hours to 3 conditions: (1) warm W = 21 deg C air; (2) Cold C = -7 deg C air; and (3) Shiver suppression (SS)= -7 ... |
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| Thermoregulatory Effects of Atropine in the Cold using a Hypotrichotic Rat Model. |
13 MAY 1993 |
|
| Authors:
Brian J. Gentile; Craig R. Johnson; Ralph P. Francesconi; Roger W. Hubbard; ARMY MEDICAL RESEARCH INST OF CHEMICAL DEFENSE ABERDEEN PROVING GROUND MD
|
| The objectives of this research were to determine the effects of atropine on shivering and peripheral-vasodilation in the cold, with attendant effects on thermoregulation. A conscious, confined but unrestrained, hypotrichotic (Wistar-Furth, fuzzy) rat model was used. Electromyography (EMG) was utilized to assess the shivering response of the trapezius muscle. An EMG frequency band between 3 Hz and 1 kHz was rectified, then integrated for determination of a shivering index. Infrared ... |
|
| Physiology Data Acquisition System Description |
01 OCT 90 |
|
| Authors:
Mark L. Lotz; NAVAL BIODYNAMICS LAB NEW ORLEANS LA
|
| This technical report describes the Physiology Data Acquisition System used at NAVBIODYNLAB to acquire, record, and reproduce physiologic responses from human research volunteers subjected to short duration accelerations. The system is used to acquire data such as electrocardiograms, electromyograms, and somatosensory evoked responses. The impact accelerations are provided by horizontal and vertical accelerators. This report describes the systems used for physiology data acquisition during experiments performed on the horizontal and ... |
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| Enhancing the Tolerance of +GZ Acceleration by Optimizing the Use of Isometric Contractions in Combination with Straining Maneuvers |
AUG 90 |
|
| Authors:
Carole A. Williams; J. Martin; J. Moffatt; J. E. Douglas; A. R. Lind; EAST TENNESSEE STATE UNIV JOHNSON CITY DEPT OF PHYSIOLOGY
|
| Experiments were performed on 9 male subjects who exerted L-1 straining maneuver in a pilot chair apparatus with a seatback at 30 degrees and a spine-to-thigh angle of 110 degrees. The L-1 maneuvers were performed with or without simultaneous application of isometric contractions. Contractions were exerted at high levels of force in either a sustained fashion or in an intermittent fashion, in 15 sec periods, until fatigue occurred. Isometric contractions ... |
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| The Effect of Concurrent Strength and Endurance Training on Electromechanical Delay, Maximum Voluntary Contraction, and Rate of Force Development |
AUG 89 |
|
| Authors:
D. G. Bell; I. Jacobs; D. G. Sale; J. D. MacDougall; DEFENCE AND CIVIL INST OF ENVIRONMENTAL MEDICINE DOWNSVIEW (ONTARIO)
|
| This study compared the effect of strength and endurance training and their combination on electromechanical delays (EMD), rate of force development (RFD) and maximum voluntary isometric contraction force (MVC) of the knee extensors in male and female subjects. The seven male and six female subjects were separated into a strength trained group (SG), 3 males and 3 females, and an endurance group (EG), 4 males and 3 females. The SG ... |
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| Loads Carried by Soldiers: Historical, Physiological, Biomechanical and Medical Aspects |
JUN 89 |
41 pages |
| Authors:
Joseph Knapik; ARMY RESEARCH INST OF ENVIRONMENTAL MEDICINE NATICK MA
|
| Loads currently recommended by the U.S. Army Infantry school are 33 kg for an approach march load (45% of body weight) and 22 kg for a combat load (30% of body weight). Methods of reducing loads include the use of lightweight technology, load tailoring, auxiliary transport systems, doctrinal changes, and physical training. Specific physiological factors involved in load carriage include aerobic capacity and muscle strength. The specific muscle groups involved ... |
|
| Assisted Positive Pressure Breathing for Augmentation of Acceleration Tolerance Time |
MAR 88 |
|
| Authors:
John W. Burns; Ulf I. Balldin; SCHOOL OF AEROSPACE MEDICINE BROOKS AFB TX
|
| The addition of assisted (chest counterpressure), positive pressure breathing at 50 mm Hg and 70 mm Hg was compared to the current operational support of the G-suit and the anti-G straining maneuver (AGSM) without PPB, during acceleration exposures of sustained 9 +Gz for 45 s and a 5-9 +Gz simulated aerial combat maneuver (SACM) to exhaustion. We selected 7 highly motivated male centrifuge subjects from a group of 31 volunteers. ... |
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| The Effects of Biodynamic Stress on Workload in Human Operators |
JAN 88 |
|
| Authors:
William B. Albery; HARRY G ARMSTRONG AEROSPACE MEDICAL RESEARCH LAB WRIGHT- PATTERSON AFB OH
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| The objective of this research was to assess the effect of high intensity noise stress and of sustained acceleration on human operator workload and performance. Workload was measured via three different methodologies. Subjective workload was measured with the Subjective Workload Assessment Technique (SWAT); performance-based measures were derived from single and dual psychomotor task performance; and physiological parameters included heart rate, blood pressure, total eye blinks duration, forearm electromyogram and evoked ... |
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| The Relationship between Changes in Arterial Pressure, Esophageal Pressure and the EMG (Electromyography) of Various Muscle Groups during the L-1 Straining Maneuver at Different Spine-to-Thigh Angles |
JUL 87 |
52 pages |
| Authors:
Carole A. Williams; J. E. Douglas; Gary Miller; A. Karl; R. L. Wiley; SYSTEMS RESEARCH LABS INC DAYTON OH
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| Changes in arterial blood pressure, intrathoracic pressure, heart rate, and the electromyographic activity of various muscle groups were determined while 9 male subjects performed L-1 straining maneuvers at four spine-to-thigh angles (70, 84, 94, and 105 deg). There was no significant difference between the changes in these physiological variables due to the different angles. At the onset of the L-1, arterial pressure immediately increased to an average of 195 mm ... |
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| Controlling the Temporal Structure of Limb Movements: A Response |
MAY 86 |
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| Authors:
Richard A. Schmidt; CALIFORNIA UNIV LOS ANGELES MOTOR CONTROL LAB
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| This report is a response to a recent article by Berkinblit, et.al., which suggested that motor-program models, in which a centrally programmed temporal structure was a key ingredient, seemed incorrect. In particular, Schmidt takes issue with their discussion of Fel'dman's (1974) mass-spring model which denies a central program for limb movement timing and amplitudes. Schmidt argues that evidence for unidirectional actions and sequential movements limits the utility of the mass-spring ... |
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| Psychophysiological Studies II. Performance and Physiological Response in Coronary Prone and Noncoronary Prone Individuals |
30 JAN 86 |
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| Authors:
John L. Andreassi; N. Mauro Juszczak; BERNARD M BARUCH COLL NEW YORK PSYCHOPHYSIOLOGY LAB
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| This final report details the background, findings, and conclusions of two studies completed in the Psychophysiology Laboratory of Baruch College, City University of New York, over the past twelve months. In Experiment I 36 individuals, 18 classified as Type A and 18 as Type B using the Jenkins Activity Survey, performed a perceptual-motor task (simulated race car driving) along with a secondary task (simple reaction time) while a number of ... |
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| Electro-Mechanical Response Times and Rate of Force Development in Males and Females |
86 |
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| Authors:
Douglas G. Bell; Ira Jacobs; DEFENCE AND CIVIL INST OF ENVIRONMENTAL MEDICINE DOWNSVIEW (ONTARIO)
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| Muscle force development is influenced by both central (pre-motor end plate) and peripheral (post-motor end plate) components. Conflicting results are available concerning gender-related differences in the central component. This study compared males and females with regard to the following electro-mechanical response variables: total reaction time, pre-motor time, electro-mechanical delay, and the rate of force development durig a maximal voluntary isometric contraction (MVC) of the elbow flexors. Forty-six males and 40 ... |
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ELECTROMYOGRAPHY
