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Biomedical subjects

M E McCauley

Publications and source records attributed to M E McCauley.

10 recordsLinked to original sources
PubMed1996

The effect of imagery on explicit and implicit tests of memory in young and old people: a double dissociation.

The use of imagery as an elaborative study task was examined to determine its effects on implicit and explicit tests of memory in both young and old adults. Both the implicit and explicit tests were word-stem completion tests, identical except for their instructional content. Results showed that imaging the referent of a visually-presented word during the initial study period significantly improved the performance of the young adults on the explicit test of memory, but reduced their performance on the implicit test. The test results of the elderly subjects showed a similar trend in that explicit test performance was significantly improved following an imagery study task whereas implicit test performance was reduced following this same task. These results did not, however, reach the level of significance, observed for young adults. The results are discussed within the framework of a processing account of implicit/explicit dissociations.

Adult↗
PubMed1993

Autonomic physiological data associated with simulator discomfort.

A physiological monitoring capability was developed for the Army's Crew Station Research and Development Facility (CSRDF), a research simulator for advanced rotorcraft. Preliminary physiological data are reported from studies of simulator-induced sickness. Our objective was to demonstrate sensitivity of physiological measures relative to self-reports of simulator sickness severity. The data suggested that heart period, tachygastria, and skin conductance level were more sensitive to simulator sickness than were vagal tone and normal myoelectrical gastric activity.

Aerospace Medicine↗
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↗
PubMed1982

Motion sickness incidence induced by complex periodic waveforms.

Independent groups of up to 32 young men exposed in a standard seated posture to one of five conditions of vertical (Z axis) motion for up to 2 h. Exposure was less in the event of vomiting or a volunteer's voluntary withdrawal from the experiment. A control condition, sinusoidal motion of 0.17 Hz and 0.13 G R.M.S., provided the basis for comparison with the remaining four conditions, each produced by the sum of two sinusoids, the fundamental at 0.17 Hz plus the second or third harmonic. The conditions differed in the phase relationship of the fundamental and second harmonic, or in the relative acceleration levels of the two harmonic components. The predicted motion sickness incidence (MSI) for each sinusoid alone was calculated from a previously derived mathematical model and compared with the obtained MSIs. Certain motion conditions provoked unexpectedly high MSIs compared with the control condition. It was found that R.M.S. acceleration is not reliable as the sole predictor of MSI in complex motion. Further data must be obtained before accurate prediction of MSI in broadband motion will be possible.

Acceleration↗
PubMed1980

Development of performance evaluation tests for environmental research (PETER): time estimation.

A time-estimation task was considered for inclusion in the Performance Evaluation Tests for Environmental Research (PETER) battery. As part of this consideration, the effects of repeated testing on the reliability of time judgments were studied. The method of production was used to estimate eight time intervals. Five trials per day at each interval were administered individually to each of 19 subjects for 15 consecutive workdays. Two scores, constant error and variable error, were reported. The effect of days was not significant for constant error and was moderate for variable error (p < .04). The standard deviations were relatively stable across trials. A pronounced decline in reliability over repeated days of testing was found for both errors. It was concluded that this time-estimation test would be a poor candidate for inclusion in PETER, but further research is warranted because of the potential unique contribution of a time-estimation task in a performance test battery.

Adult↗
PubMed1979

Effect of transdermally administered scopolamine in preventing motion sickness.

The efficacy of transdermally administered scopolamine was compared with the efficacy of oral dimenhydrinate and placebo therapy in the prevention of motion-induced mausea in a vertical oscillator; medications were administered on a double-blind cross-over basis, with the order of treatments counterbalanced. Thirty-five subjects known to be susceptible to the stimulus were utilized. A placebo effect reduced the motion sickness incidence (MSI) from 100% to 59%. Administration of dimenhydrinate reduced the MSI to 32%, and use of the transdermal therapeutic system scopolamine (TTS-scopolamine) further reduced the MSI TO 16%. TTS-scopolamine afforded 73% protection against motion-induced nausea, compared to 46% protection with dimenhydrinate. The TTS-scopolamine is designed to remain in the body for 72 hours, providing advantages over intramuscular or oral administration of scopolamine, which include reduced daily dosage, and an effective alternate to the gastrointestinal tract for administrating medication at times of gastrointestinal distress.

Administration, Topical↗
PubMed1979

Susceptibility to seasickness: influence of hull design and steaming direction.

Three sea going vessels steamed side by side through slight seas off the coast of Oahu, Hi. A 4-h octagon was transmitted twice each day for three consecutive days while motion sickness symptomatology was recorded from 18 enlisted men who alternated among the vessels. Dramatic differences in illness severity were obtained whether comparisons were made using objective evidence of vomiting episodes or subjective reporting of symptoms on questionnaires. Reliability of this scoring method was excellent (r = .95). In addition to face and construct validity, evidence is presented of the predictive validity of the scoring method in a separate octagonal steaming experiment using a 95 ft Coast Guard patrol boat in an equivalent experimental paradigm. This study showed significant covariance between the magnitude of motion sickness symptomatology and the encounter direction of the vessel to the primary swell (p less than 0.01). Additionally, significant correlations were found between sickness severity and test subject concentration, fatigue, urine production, and urine specific gravity. The majority of these relationships would not have been disclosed had only the dichotomous criterion of vomit/nonvomit been employed in assessing motionsickness severity. Implications of these data as design criteria for marine vehicles are discussed.

Adult↗