Biomedical subjects

M G Lilienthal

Publications and source records attributed to M G Lilienthal.

6 recordsLinked to original sources

PubMed1997

Disorientation and postural ataxia following flight simulation.

BACKGROUND: Motion sickness-like symptoms can afflict pilots training in military simulators. This simulator sickness involves symptoms of gastrointestinal distress, eyestrain and disorientation. A simulator sickness Questionnaire (SSQ) with subscales available for each of these dimensions has been developed to assess the problem. HYPOTHESIS: This study examined the hypothesis that there is a strong correlation between the SSQ subscale which summarized self report of disorientation symptoms and an objective measure of post-simulation postural instability. METHODS: Data from two Navy simulators were analyzed: Device 2F114, a Weapon System Trainer for the A-6E Intruder, and Device 2F143, an Operational Flight Trainer for the EA-6B. Tests of standing and walking unsteadiness were administered along with the Simulator Sickness Questionnaire (SSQ). RESULTS: Significant correlations were found between scores on postural stability tests and the SSQ disorientation subscale scores, but correlations between scores on postural stability tests and the SSQ nausea and oculomotor subscale scores were much weaker and not statistically significant. CONCLUSIONS: These results provide some evidence for the validity of the disorientation subscale of the SSQ and suggest that the postural instability observed after simulator exposure may, in fact, result from disorientation.

Aerospace Medicine↗

PubMed1995

Defense Simulation Internet: next generation information highway.

The Department of Defense has been engaged in the Defense Modeling and Simulation Initiative (DMSI) to provide advanced distributed simulation warfighters in geographically distributed localities. Lessons learned from the Defense Simulation Internet (DSI) concerning architecture, standards, protocols, interoperability, information sharing, and distributed data bases are equally applicable to telemedicine. Much of the vision and objectives of the DMSI are easily translated into the vision for world wide telemedicine.

Computer Communication Networks↗

PubMed1993

Postural and performance changes following exposures to flight simulators.

Flight simulators are cost-effective, safe, and flexible training tools for aviators. However, their advantages may be offset by the occurrence of motion sickness-like symptoms which have been reported during and following simulator training. Although symptoms have been well documented in simulators, their time course, causes, and implications for training are not yet fully understood. Tests of standing and walking steadiness were administered along with cognitive and motor performance tests to Navy and Marine Corps aviators before and after their regular simulator training, resulting in records of 726 pilot exposure observations. When exposed pilots were compared to a control group who did not fly in a simulator, statistically significant decrements in postural equilibrium test scores were found for all of the moving base simulators, but for only one of the three fixed-base simulators. The size of these losses was approximately 15% of baseline. Cognitive and motor changes, while statistically significant, were complicated by learning effects in all groups for all tests. When compared to the control group, improvement in cognitive scores was always less in the simulator groups, but greater improvement occurred in the simulator groups for motor speed scores, although this latter difference was small (< 1% of baseline). Further study of performance changes is recommended. In those simulators where significant effects occurred, the ataxia and the time-course of the disequilibrium should be followed.

Aerospace Medicine↗

PubMed1992

Use of a motion sickness history questionnaire for prediction of simulator sickness.

This research assessed the usefulness of the Motion History Questionnaire (MHQ) for the prediction of simulator sickness, a form of motion sickness experienced by pilots training in ground-based flight simulators. Four MHQ scoring keys were compared: (1) the original MHQ key which had been validated on a sample of U.S. Navy student pilots exposed to Coriolis forces, (2 and 3) two keys which had been validated on a sample of civilian college students exposed to simulated ship motions, and (4) a simulator sickness key empirically derived in the present research and cross-validated. Navy and Marine Corps aviators (N = 456) filled out the MHQ prior to their regularly scheduled flight simulator training and were divided into validation and cross-validation samples. All scoring keys were predictive of reported symptoms of sickness, but highest correlations were obtained with the empirically-derived simulator sickness (SS) key. It is suggested that the SS key be used for self-testing so that pilots may be made aware of their risk for developing simulator sickness.

Aerospace Medicine↗

PubMed1989

The time course of postflight simulator sickness symptoms.

Reports of posteffects following training sessions in Navy and Army flight simulators were obtained from pilots to determine the time course of recovery from simulator sickness. Results imply that posteffects may be a more serious problem than previously considered; 45% of all those queried (N greater than 700) reported having experienced symptoms of simulator sickness; 25% of the symptoms lasted more than 1 h after leaving the simulator; and 8% lasted more than 6 h. Postexposure symptoms were classified into three categories: visuomotor (based on disturbances in oculomotor control; e.g., eyestrain), disorientation (based on disturbance in postural control; e.g., dizziness), and nausea (vagal/autonomic symptoms). A safety risk may be posed particularly by the moderately high frequency of symptoms involving postural disequilibrium. Guidelines for coping with risks are discussed.

Adaptation, Psychological↗

PubMed1989

Simulator sickness in U.S. Navy flight simulators.

Flight simulators have become a major factor in pilot training. A general finding from Navy research on simulator design is that equipment features that offer faithful representation improve pilot performance and promote pilot acceptance. To the extent that an aircraft produces motion sickness, its simulator should induce the same result. However, reports of simulator sickness appear to be increasing and a shortcoming in simulation is implied when these effects occur in simulators during maneuvers that do not occasion them in the aircraft. This article presents incidence data from surveys of the 10 simulators at 6 different Naval/Marine Corps Air Stations. Approximately 1,200 simulator flights were recorded. Some severe motion sickness symptoms were recorded and some simulators induced unsteadiness afterwards. Individuals experiencing effects may be at risk if they drive themselves home or return to demanding activities at work. The simulators which exhibited the highest incidences of sickness were helicopter simulators with cathode ray tube (CRT) infinity optics and six-degrees-of-freedom moving base systems. Of those studied, fixed-wing, fixed-base, dome displays had relatively low incidence of simulator sickness.

Aircraft↗