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Games: a way to give laboratory values meaning.

Through the use of gaming techniques patients may acquire a better understanding of the significance of serum laboratory values and their relationships to the disease process and treatment regimen. Games provide practitioners with an alternative teaching strategy that may be used to reinforce learning and positively change health beliefs and behaviors that will ultimately promote compliance with the treatment regimen.

Game Theory↗

Review of the phase I and phase II teaching programmes in the School of Medical Sciences, Universiti Sains Malaysia.

The Phase I and Phase II undergraduate teaching programmes of the School of Medical Sciences were reviewed at the end of the 1985/86 academic year. It was found that deviations from the School's philosophy had crept into the implementation process. Modifications were therefore made in Phase I and Phase II programmes with a view to:--(i) reducing content, (ii) promoting integration, (iii) improving clinical examination skills of students, and (iv) providing more opportunities to students for self learning, reinforcement and application of knowledge. The number of assessment items in Phase I and the frequency of assessment in Phase II were also found to be inappropriate and so modifications in assessment were made to rectify this situation.

Curriculum↗

Dietary management in diabetes mellitus. A goal-setting process.

Diet is a cornerstone to the management of diabetes mellitus. A successful diet will provide the necessary elements for good nutrition, maintain near normal plasma glucose ranges, and be acceptable to the patient. Persons with diabetes have differing physiologic requirements and varying lifestyle needs; therefore, an individualized dietary management program should be designed for each patient. Teaching the person with diabetes about the dietary management protocol is an ongoing process that should include all members of the health care team. With an understanding and appreciation of the goals of the diabetic diet, the nurse can evaluate the management program and reinforce learning with an anticipation that adherence to the diet will enhance the health and quality of life of the diabetic patient.

Diabetes Mellitus↗

Association between the elements of a bivalent compound stimulus.

Evidence that an association forms between the elements of a bivalent compound stimulus during inhibitory training was provided in four experiments with rats in a conditioned suppression task. This association occurred both in a conditioned inhibition paradigm, which intermixed A+ and AX- trials (Experiments 1 and 2), and in an extinction-inhibition paradigm, which presented A+ and AX- training sequentially (Experiments 3 and 4). The within-compound association appeared to be bidirectional inasmuch as excitatory changes in the value of either component affected responding to the associated component. After inhibitory training in Experiments 1-3, pairings of the inhibitory stimulus (X) with shock increased suppression to the associated excitatory stimulus (A). In Experiment 4, additional pairings of the excitatory stimulus (A) with shock after inhibitory training increased suppression to the associated inhibitory stimulus (X). These studies add to a growing body of evidence on within-compound associations and encourage the development of a conceptual framework that provides an integrated description of within-compound and stimulus-reinforcer learning.

Animals↗

Teaching literature searching in the context of the World Wide Web.

As part of the required curriculum for medical students, we devised a literature-searching practicum that has been used for two years. In both years, we stressed going beyond the skills needed for using a particular searching program, towards a more conceptual approach to information searching. In the first year, the practicum was taught in a traditional lecture/hands-on format. In the second year, the lecture was replaced by a World Wide Web-based tutorial (http:@www.welch.jhu.edu/Education/tutorials/pra cticum.html). To our knowledge, this is the first Web-based resource intended to teach students about appropriate use of search technology. Comparison of student evaluations showed no difference in attitude toward the two versions of the practicum, and observation of student performance suggested similar levels of proficiency. We conclude that placing these educational materials on the Web (1) makes us practice what we preach; (2) is as effective as traditional teaching methods; and (3) gives students a resource for reinforcement learning.

Computer Communication Networks↗

Effects of entorhinal cortex lesion on learning behavior and on hippocampus in the rat.

The initial stage of Alzheimer's disease is characterized by a neuropathological change in the entorhinal cortex. In a previous study it was shown that rats with excitotoxic lesion of entorhinal cortex showed an impaired acquisition of passive and active avoidance responses. In this study a rat with excitotoxic lesion of the entorhinal cortex was tested for 'more operant' behavioral learning (i.e., positive reinforcement operant learning). The hippocampus was also examined histologically as acetylcholinesterase-stained sections, and as synaptophysin immunostained sections and examined biochemically by liquid chromatography. Eight weeks after operation, the bilateral entorhinal cortex lesioned rats showed an impaired acquisition of positive reinforcement operant learning. The lesioned side of unilateral entorhinal cortex lesioned rats showed a decrease of acetylcholinesterase-positive fibers in the CA3, the dentate gyrus, and of synaptophysin-positive substances in the CA3. Biochemical study showed a decreased level of acetylcholine in the CA3, and in the dentate gyrus. The histological and biochemical findings are interpreted as indicating that the entorhinal cortex of the rat provides the major extrinsic synaptic input to the hippocampal formation via the circuit which serves as a relay passage through the dentate gyrus and via direct projections into the hippocampus. Behavioral findings confirmed the importance of the entorhinal cortex in memory acquisition and indicated that rats with a partial neuronal loss in the entorhinal cortex may be a useful model for the memory disturbance of Alzheimer's disease.

Acetylcholine↗

The nature of reinforcement in cerebellar learning.

In a now classic study, W. J. Brogden and W. H. Gantt (1942, American Journal of Physiology, 119, 277-278) demonstrated that movements (limbs, head, eyelid) elicited by direct electrical stimulation of certain regions of the cerebellum (particularly the ansiform lobe) could be trained to respond to neutral auditory or visual conditioned stimuli with appropriate pairing. In recent work we have replicated these results in detail and presented considerable evidence that the reinforcing or "teaching" pathway so activated for the learning of discrete movements is the inferior olive-climbing fiber projection system to the cerebellum. Very strong evidence now indicates that the memory traces for this "skilled response" learning are formed and stored in the cerebellum. The climbing fiber system and inhibitory pathway from the interpositus nucleus to the inferior olive appear to form a neural instantiation of the Resorla-Wagner formulation of classical conditioning and accounts for the "cognitive" phenomenon of blocking. It is concluded that reinforcement in this form of learning is not due simply to contiguity/contingency or to unconditioned stimulus aversiveness, per se, but rather to activation of a particular brain circuit, here the climbing fiber system, a circumstance that may apply to other forms of learning, with other reinforcement circuits, as well.

Animals↗

Specific features of learning with nociceptive electrical reinforcement in rats of different genetic strains: role of brain neurotransmitter systems.

The interaction between neurotransmitter systems and opioid system in rats of different strains was studied during learning and emotional stress. The interaction between noradrenergic, serotoninergic, and opioid systems in the brain is the main neurochemical mechanism underlying learning reinforced by nociceptive electrical stimulation, which determine individual differences in the rate and type of learning.

Animals↗

[Effects of bilateral amygdalectomy on levers pressing for food reward in the rabbit (author's transl)].

Effects for continuous reinforcement (CRF) learning and differential reinforcement of low rate (DRL) learning for food in the rabbit by bilateral amygdalectomy were examined with the Skinner box. There was no changes in general behaviour and no impediment of CRF learning. But the completion of DRL learning was delayed by amygdalectomy. In the stage of completion of DRL learning there was no difference of total number of the reinforcement and the lever pressing between the control group and amygdalectmized group. But there was the impediment of DRL learning by the analysis of frequency distribution of inter-response time and of transition probability matrix in the amygdalectimized group. We thought that this impediment of DRL learning was due to the impediment of selection of decision of lever pressing action. The memory of the preamygdalectomy was maintained well after amygdalectomy.

Amygdala↗

Learning, using natural reinforcements, in insect preparations that permit cellular neuronal analysis.

A general paradigm is described that permits testing the ability of an arthropod to learn (by operant conditioning) to alter the position of a single leg segment in order to relate to behaviorally appropriate reinforcement. The paradigm was designed so that intracellular recording from identified neurons involved would be possible during the training of a locust or grasshopper, for which extensive neuron maps are available. As a prelude to such studies, electromyograms were made from the antagonistic muscles that move the conditioned limb, which in the present experiments was the tibia of the metathoracic leg. Negative (aversive) reinforcement was provided by a loud sound/vibration and positive (reward) reinforcement by food in the form of sugar-water or fresh-growing grass. In the aversive reinforcement experiments the sound, which reflexly caused flexion, was on continually except when the tibia of one hind leg was voluntarily placed in an electronically set position "window" displaced, in extension, away from the preferred position. In feeding experiments, food was brought automatically to the mouth by a motor-driven arm when the tibia was held within a position window set away from the preferred position in either extension or flexion. Whole or headless insects learned to turn off the sound permanently, except for sporadic brief interruptions, by tonic shifting of tibial position. Insects learned to bring food to the mouth by modifying the plateau phase of a position displacement lasting for a few minutes, that was found to occur from time to time also in controls. In aversive learning, minimum times to turn off the sound were 22 sec for the easiest position and 4 min for the most difficult. The longest time in the easiest position was 1 min 40 sec and in the most difficult 39 min; excluding measurement for individuals that did not learn. In reward learning, the minimum time in the easiest position was just under 1 min, and 12 min in the most difficult position. The longest times were about 8 hr regardless of difficulty.

Animals↗