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Biomedical subjects

J Dickinson

Publications and source records attributed to J Dickinson.

At least 73 records · Page 4Linked to original sources
PubMed1983

Stimulus generalization and the peak shift with movement stimuli.

Stimulus generalization is suggested as an alternative method for examination of the "novelty" problem in motor learning. These experiments demonstrated that stimulus generalization occurs using simple movements as stimuli. The phenomenon of the "peak shift" in post-discrimination generalization gradients was also examined. The first experiment demonstrated that a peak shift occurred using linear movements as stimuli and that the magnitude of the peak shift increased as the difference between the training stimuli decreased. The second experiment showed similar results when the stimuli consisted of a range of movements rather than single movement length. The final experiment provided evidence that perception of movement length is influenced by the magnitude of an immediately preceding movement. The relevance of these studies to current motor-learning theory is discussed.

Journal Article↗
PubMed1983

The effect of distance and location cues on linear arm positioning by children.

Forty-five boys in each of three age groups learned a 40 cm linear arm movement, without the aid of vision. Fifteen in each age group attempted to reproduce the movement using either distance, location, or distance plus location cues. Analysis of absolute error scores showed a significant effect of movement cue with inferiority in recall using distance cues compared with the other cue conditions. The interaction effect was also significant. The results are discussed in terms of the development of coding systems for movements in short-term memory.

Adolescent↗
PubMed1983

Altitude-related deaths in seven trekkers in the Himalayas.

The clinical features and necropsy findings are described for seven trekkers in the Himalayas whose deaths were related to high altitude. The fatal outcome was due to serious pulmonary and cerebral disease. Oedema of the lungs and brain was prominent but so was thrombosis and haemorrhage, features of acute mountain sickness that have received insufficient recognition in the past. Most of the men were middle aged. Some began their trekking soon after flying to high altitude before becoming acclimatised and some remained at high altitude or climbed even higher despite the development of vomiting, breathlessness, and exhaustion. In one case death occurred despite prompt recognition and treatment of symptoms by administration of oxygen and swift evacuation to low altitude.

Adult↗
PubMed1982

Psychosocial bias in the diagnosis of obesity.

This study explores demographic and psychosocial variables associated with the assignment of the diagnosis of obesity in a family medicine residency model practice. Three groups of adult patients seen during 1978 were studied: a random sample of active patients, patients diagnosed as obese during 1978, and those never diagnosed as obese. While the prevalence of true obesity (greater than 20 percent above ideal body weight) was similar for men (58 percent) and women (47 percent), more women were diagnosed (222 women vs 87 men) and were more likely to be diagnosed within a year of entering the practice (42 percent women vs 10 percent men). Diagnosed obese women were older, had more psychological problems, and visited the practice more often than nonobese women. Diagnosed obese men were older, more frequently had psychological problems, visited the practice more often, and were more likely to be married than nonobese men. Undiagnosed obese men, however, had fewer psychological problems than nonobese men. The results suggest that physician education should address problems with diagnostic labeling and that researchers should anticipate subtle selection biases in retrospective studies when sampling methods depend on diagnosis.

Adult↗
PubMed1981

Preventive dental health in adolescents: short and long term pupil response to trials of an integrated curriculum package.

A controlled evaluation of a 3-week teacher mediated dental health education curriculum package was undertaken in 35 English secondary schools in three Area Health Authorities. 4500 13-14-year-old adolescents were involved. The package emphasized self-care potential and combined a scientifically accurate message with educational and behavioural science concepts. Evaluation was at the levels of process and outcome using changes in oral hygiene recorded on a random sample (n = 1491) by two trained examiners; self-complete pre/posttest questionnaires, pupil worksheets and home experiment diaries. Behavioural, cognitive and affective outcomes are reported. Significant improvements in oral hygiene status were recorded at the conclusion of the programme along with large gains in knowledge and positive changes in attitude. Long term follow-up oral hygiene examinations in six schools (n = 145) conducted in conjunction with a reinforcement programme, indicated a maintenance of the initial improvements in five schools. Further significant improvements were measured after the reinforcement programme.

Adolescent↗
PubMed1979

Warm- and fatigue in skill acquisition and performance.

Two experiments examined the effects of preliminary exercise on performance and learning of the Fitts' reciprocal tapping task. In the first experiment preliminary exercise was performed with either the preferred or nonpreferred arm. The tapping task was completed with the preferred by both groups. Low levels of preliminary exercise resulted in heightened performance for both groups, but higher levels resulted in a decrement for the group using the preferred arm. An arousal-plus-fatigue hypothesis can explain the results. A subsequent post-test without preliminary exercise showed no difference between the groups, indicating an effect on performance and not learning. In the second experiment preliminary exercise was provided by treadmill running to exhaustion. Again, a facilitatory effect of exercise was demonstrated on tapping performance even after exhaustive levels of running.

Journal Article↗
PubMed1978

Perception of blur in optometric test.

Sensitivity to blur detection was measured for 30 optometric patients by having them match the clarity [or blur] of the target words at the test endpoint with 1 of an identical set of photographically defocused words. The group showed considerable variance in their blur scores which approached a normal distribution. Some clinical implications are discussed.

Adolescent↗
PubMed1977

Distance and location cues in retention of movements by a congenitally blind subject.

Retention of linear arm-positioning movements in a congenitally blind university student was tested with either distance or location cues and under retention conditions of rest, location, and distance interpolated tasks. Results revealed a consistent superiority for retention with location cues. The conclusion is drawn that these data would support a dual proprioceptive storage mode hypothesis.

Adult↗
PubMed1977

Adaptation level and retroactive interference in motor short-term memory.

5 groups of 10 subjects were required to make and recall a linear self-generated arm-positioning movement. 4 of the groups made and recalled 4 interpolated self-generated positioning movements before the recall of the criterion was attempted. The lengths of the interpolated movements relative to the criterion varied from group to group. For one group all interpolated movements were longer, for another they were all shorter, and two groups produced alternating shorter and longer movements. Results indicated a significant difference in percentage algebraic error at recall of the criterion movement between the groups experiencing longer and experiencing shorter interpolated movements. The evidence is suggestive of two components in retroactive design studies, interference and adaptation level.

Adaptation, Physiological↗
PubMed1976

Where shall John go?

Explore the source record for details and available documents.

Cultural Characteristics↗
PubMed1975

Cerebral form of high-altitude illness.

Twelve cases of severe altitude illness are reported in which the neurological signs and symptoms dominated the clinical picture. Pulmonary oedema, retinal haemorrhage, thrombophlebitis and pulmonary embolism, bronchopneumonia, and coronary-artery disease were also present in several of the patients but the primary problem seems to have been cerebral oedema. Other published cases support this impression. Patients who were returned to low altitude early in the disease fared well; two patients died, and in both cases evacuation had been delayed. The most effective prevention lies in slow ascent, though in one case reported here the rate of climb was well within the recommended limit. Recommended management is rapid descent to low altitude at earliest indication of cerebral or pulmonary oedema, intravenous dexamethasone or betamethasone in large doses, hydration, diuresis (frusemide has been most used), and perhaps other intravenous therapy with hyperosmolar materials such as mannitol, urea, 50% saline, or 50% sucrose. Prognosis is good if descent and treatment are started early, but permanent damage may be anticipated if the patient is unconscious for any prolonged period before descent.

Adult↗