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P N Wilson

Publications and source records attributed to P N Wilson.

14 recordsLinked to original sources
PubMed1998

A rejoinder.

Explore the source record for details and available documents.

Persons with Disabilities↗
PubMed1998

Uses of virtual reality in clinical training: developing the spatial skills of children with mobility impairments.

In this chapter we review some of the ways in which the skills learned in virtual environments (VEs) transfer to real situations, and in particular how information about the spatial layouts of virtual buildings acquired from the exploration of three-dimensional computer-simulations transfers to their real equivalents. Four experiments are briefly described which examined VR use by disabled children. We conclude that spatial information of the kind required for navigation transfers effectively from virtual to real situations. Spatial skills in disabled children showed progressive improvement with repeated exploration of virtual environments. The results are discussed in relation to the potential future benefits of VR in special needs education and training.

Computer Simulation↗
PubMed1997

Virtual reality, disability and rehabilitation.

Virtual reality, or virtual environment computer technology, generates simulated objects and events with which people can interact. Existing and potential applications for this technology in the field of disability and rehabilitation are discussed. The main benefits identified for disabled people are that they can engage in a range of activities in a simulator relatively free from the limitations imposed by their disability, and they can do so in safety. Evidence that the knowledge and skills acquired by disabled individuals in simulated environments can transfer to the real world is presented. In particular, spatial information and life skills learned in a virtual environment have been shown to transfer to the real world. Applications for visually impaired people are discussed, and the potential for medical interventions and the assessment and treatment of neurological damage are considered. Finally some current limitations of the technology, and ethical concerns in relation to disability, are discussed.

Activities of Daily Living↗
PubMed1996

Transfer of spatial information from a virtual to a real environment in physically disabled children.

A group 10 severely physically disabled children explored a to-scale computer simulation of a real multi-storey building. Following exploration, their knowledge of the spatial properties of the real environment was assessed by asking them to point to fire apparatus that was not visible from the test site. Subjects in a control group were asked to complete the same assessment tasks, but without the opportunity to explore either the real building or the computer simulation. The estimates of the disabled children were superior to the control group indicating good transfer of spatial knowledge. Route finding and recognition reports provided support for the pointing data in indicating good transfer of spatial information.

Child↗
PubMed1992

Effects of discrimination training on responding during a compound conditioned stimulus.

Four experiments examined responding in the presence of a triple-element compound ABC after discrimination training in which 2 compounds, AB and BC, signaled the delivery of food and 1 element alone, B, signaled the absence of food. In Experiments 1 and 2, using rats, responding during ABC was more vigorous than in a control group for which A and C but not B had been individually paired with food. This finding was replicated in Experiment 3, which used pigeons, and in Experiment 4, where all 3 stimuli of the control condition were individually paired with food. The results are more consistent with a configural than with an elemental theory of learning.

Animals↗
PubMed1992

A configural analysis for feature-negative discrimination learning.

In 4 experiments, rats were initially trained with an A+ AXo discrimination in which Stimulus A by itself signaled the delivery of food, A+, whereas the simultaneous presentation of A and X was followed by nothing, AXo. In each experiment X was then paired with food prior to a test phase in which A and X were again presented for a discrimination. The discrimination was of the form A+ AXo in Experiments 1 and 2, whereas it was of the form X+ AXo for Experiments 3 and 4. In all 4 experiments the test discrimination was acquired more rapidly than a control discrimination. The results are interpreted in terms of the original A+ AXo discrimination resulting in the growth of an association between a representation of the entire AX compound and the effects of nonreinforcement.

Animals↗
PubMed1990

Selective transfer of responding in conditional discriminations.

In each of three experiments rats received discrimination training in which whether or not a 10-sec target stimulus was followed by food was signalled by a 2-min background stimulus. In the first experiment the target was paired with food in the presence but not the absence of the background stimulus. Subsequent tests revealed that the background elevated responding to a target that had taken part in a similar discrimination. However, it had no influence on the responses elicited by a partially reinforced conditioned stimulus. In the remaining experiments the target was paired with food in the absence but not the presence of the background. Test trials then revealed that although the background had an inhibitory influence on the responses elicited by a target from a similar discrimination, it had no influence on the responses elicited by either a partially or a continuously reinforced conditioned stimulus. Various explanations for this selective influence of a background stimulus are considered.

Animals↗
PubMed1990

Configural associations in discrimination learning.

In 4 experiments, Sprague-Dawley rats and homing pigeons received training with an A+ AB0 BC+ discrimination, in which food (+) accompanied trials with A and BC. Food was not presented (0) on trials with the compound AB. Subsequent test trials revealed that responding during C by itself, or the compound ABC, was slower than during either A or BC. Responding during the ABC compound was also found to be slower after training with the A+ AB0 BC+ than an A0 AB+ BC+ discrimination. We argue that these findings demonstrate the importance of configural associations in discrimination learning. Two accounts for the way in which these associations exert their influence are considered.

Animals↗
PubMed1989

A role for stimulus generalization in conditional discrimination learning.

In each of three experiments on discrimination learning by rats, whether or not a 10-sec target stimulus was followed by food was determined by the nature of a 2-min background stimulus that accompanied it. A conditional discrimination was employed in Experiment 1 such that background A indicated food would follow one target but not the other, whereas this relationship between the targets and food was reversed in the presence of background B. Experiment 2 employed two feature-positive discriminations. Subsequent test trials revealed that the background for one discrimination was able to enhance responding during the target for the other discrimination. Experiment 3 employed a feature-positive and a feature-negative discrimination prior to test trials in which each target was presented separately during a compound of both background stimuli. The compound enhanced responding to the target from the feature-positive discrimination and reduced it to the target from the feature-negative discrimination. We suggest that to accommodate all these findings, the best explanation is provided by a configural model of Pavlovian conditioning.

Animals↗
PubMed1985

Animal husbandry: the period 1973-1995.

In the last decade the intensification of the pig and poultry industries has continued with increases in production unit size and in efficiency. This has come about as a response to rising costs, competition and reasonable end-product prices. The dairy industry has also expanded output through increasing milk yield per cow, encouraged by favourable market support. However, efficiency of feed conversion to milk production is still not directly selected for in dairy cattle. Developments in beef cattle have been away from intensive systems of production in an effort to reduce capital expenditure and increases in sheep productivity have been largely through increased stocking rates, greater fertilizer use and better grazing systems. In the next decade there are many feasible technological advances awaiting application. The use of computer simulation is likely to assist in predicting quantitative and qualitative body compositional responses to nutrition and in increasing the efficiency of grass utilization, while microprocessor technology will be developed into artificial aids to the stockman. Studies of reproductive physiology will continue to help increase output, especially with pigs and sheep. The building of sophisticated housing is likely to be justified for pigs, poultry, dairy cattle and calves, but not for suckler beef and sheep. There is likely to be greater use of centralized breeding schemes for dairy cattle, beef cattle and sheep. The future application of technology will be limited by a number of socio-economic factors. For example, the use of milk quotas to control surplus production will act as a powerful economic constraint to increased milk production and the growing public concern over animal welfare, pollution and health aspects of animal produce will exert increasing pressure on certain systems of production.

Animal Feed↗
PubMed1983

Effect of local infusion of ouabain on human forearm vascular resistance and on response to potassium, verapamil and sodium nitroprusside.

The effect of local infusion of ouabain into the forearm vascular bed has been examined in 15 normotensive male volunteers in an attempt to define the nature of the functional abnormalities of the resistance vessels in primary hypertension. Ouabain and other drugs were infused into the brachial artery and forearm blood flow was measured by venous occlusion plethysmography. Infusion of ouabain at 2 micrograms/min for 1 h caused a 26% reduction in forearm blood flow with a small rise in systemic arterial pressure; the increase in vascular resistance was unaffected by prior treatment with phentolamine. After infusion of ouabain the dilator response to potassium was reduced by 33% but the responses to verapamil and sodium nitroprusside were unchanged. The results show that acute depression of sodium pump activity by ouabain reproduces the increased resting resistance and impaired response to potassium that are seen in hypertension. It does not reproduce the relative enhancement of responsiveness to verapamil that is also observed in the resistance vessels of patients with hypertension and this abnormality must have some other cause.

Adult↗