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261.
Base-rate effects in category learning: a comparison of parallel network and memory storage-retrieval models 总被引:1,自引:0,他引:1
W K Estes J A Campbell N Hatsopoulos J B Hurwitz 《Journal of experimental psychology. Learning, memory, and cognition》1989,15(4):556-571
Exemplar-memory and adaptive network models were compared in application to category learning data, with special attention to base rate effects on learning and transfer performance. Subjects classified symptom charts of hypothetical patients into disease categories, with informative feedback on learning trials and with the feedback either given or withheld on test trials that followed each fourth of the learning series. The network model proved notably accurate and uniformly superior to the exemplar model in accounting for the detailed course of learning; both the parallel, interactive aspect of the network model and its particular learning algorithm contribute to this superiority. During learning, subjects' performance reflected both category base rates and feature (symptom) probabilities in a nearly optimal manner, a result predicted by both models, though more accurately by the network model. However, under some test conditions, the data showed substantial base-rate neglect, in agreement with Gluck and Bower (1988b). 相似文献
262.
Recall by expert medical practitioners and novices as a record of processing attention 总被引:1,自引:0,他引:1
G R Norman L R Brooks S W Allen 《Journal of experimental psychology. Learning, memory, and cognition》1989,15(6):1166-1174
Using recall of clinical protocols as a measure of expertise in medicine has yielded disappointingly small effects. Experiments using recall of clinical laboratory data are presented to provide an explanation. In one experiment, subjects either deliberately memorized or first diagnosed and then were incidentally asked for memory. With incidental instructions, experts recalled over twice as much data as did students, but with memorization instructions, student performance approximated that of experts. Experts also showed a large advantage over students in incidental recall of data that were not relevant to the problem solution. These results suggest that expert processing in this "discrete, independent inputs" domain requires effortful analysis with minimal reliance on default values, rather than relatively effortless pattern perception reported in highly visual areas of expertise. For this area, intentional memory is a misleading measure of expertise. However, incidental memory is a valuable measure of processing during diagnosis. 相似文献
263.
Age differences in memory performance were studied in a probability sample of a cross-section of 1,491 adults living in the Detroit metropolitan area, with an oversample of those age 60 and older. Both a recall and a recognition measure were adapted to the survey context by querying respondents about the nature of the questions asked in an immediately preceding interview. Subjective memory assessment was also measured, using global memory ratings performed by the respondent, his or her spouse, and the interviewer. A clear, age-related decline in memory performance was found in this population sample. Subjective memory assessment also declined across age groups, but the relation was weaker. On the basis of multiple regression analyses of the recognition measure and the respondent's self-rated memory, which were judged to have the best measurement qualities, a substantial part of these age differences can be accounted for by differences in sociodemographic composition between age groups, by cognitive functioning and physical health. 相似文献
264.
Relationship of severity of dementia to caregiving stressors 总被引:4,自引:0,他引:4
In studies of individual differences and longitudinal changes in stress and coping among dementia caregivers, assessing severity of patient impairment is critically important. It is proposed that with the progression of dementia, cognitive impairment may steadily increase, but other stressful behavioral symptoms peak at various stages of dementia. Cross-sectional data from 49 caregiving families and longitudinal follow-up data from 48 families suggest that instrumental self-care deficits begin early in dementia, and basic self-care deficits increase with dementia severity, but that many distressing behavioral symptoms decrease in late dementia. Assessments of dementia patient severity should be multidimensional, and increases and decreases in various dementia patient stressors over time should be considered as factors influencing caregiver coping. 相似文献
265.
Models of event causation and affective processes were used to design an experimental intervention for older adults. Ss were 2 at-risk populations, recently disabled and recently bereaved, each with matched nonrisk controls. Ss were randomly assigned to a placebo-contact group, a no-contact control group, or a 4-session, 10-week intervention focused on enhancing perceived control. Dependent variables assessed were personal mastery, psychological well-being and distress, positive and negative affect, and measures of daily events and activities. The intervention was nested within a 16-month longitudinal assessment of stress and adaptation processes in a large sample of community residents. The intervention had mixed effects on reports of personal mastery, but it significantly increased engagement in desirable activities and significantly decreased psychological distress and negative affect. Effects tended to be short-lived, however. Effects of the intervention tended to be particularly significant for the disabled group. 相似文献
266.
Frontal lobe dysfunction and memory impairment in patients with chronic progressive multiple sclerosis 总被引:2,自引:0,他引:2
Deficits in semantic encoding have been described in patients with frontal lobe disease who also show memory impairments. As a group, patients with multiple sclerosis (MS) exhibit memory impairment, fail to make effective use of semantic encoding to aid memory, and perform poorly on verbal fluency and concept formation tests which are sensitive to frontal lobe damage. In the present study the semantic encoding capacity of MS patients was measured using a modification of Wicken's release from proactive interference (PI) paradigm. Individual patients varied considerably in the severity of their impairments on verbal fluency, verbal recognition memory and on Wisconsin Card Sorting Task, but even patients who evidenced both memory impairment and signs of frontal lobe dysfunction showed normal release from PI after a categorical shift. Memory disturbances in MS are unlikely to result from an incapacity for semantic encoding, which seems preserved in MS, but may arise instead from deficits in processing information rapidly. 相似文献
267.
268.
M T Phelps W A Roberts 《Journal of comparative psychology (Washington, D.C. : 1983)》1989,103(4):326-338
We studied central-place foraging in rats (Rattus norvegicus) by placing food items that varied in size and weight at the ends of a 4-arm radial maze. In Experiments 1-3, rats increasingly tended to carry food to the center of the maze as the size of those items increased. Very large food items often were hoarded in the center. Rats consumed food faster on the arms than in the center, and rats traveled faster when carrying food than when not. Blocking arm entrances increased travel time between the center and the arms and decreased food carrying at every item weight except the largest. In Experiments 4-6, important conditions that influence the degree of food-carrying behavior were discovered; these were the intersection of maze arms, the presence of a conspecific, and the use of open vs. closed maze arms. 相似文献
269.
This paper addresses the use of the weekly written summary with patients in group psychotherapy. In an effort to stimulate group process and effect cotherapist communication, the authors instituted this group recording in an ongoing psychodynamically oriented mixed adult group. While the utilization of this device did, in fact, stimulate the group process and became an important part of the group's life, the therapists additionally saw significant effects upon their working alliance. These included increased focused dialogue upon group dynamics, more purposeful planning for group interventions, and heightened awareness of the significance of interventions in the group.Ms. Bosman-Clark is formerly Clinical Instructor, Department of Psychiatry, Baylor College of Medicine. 相似文献
270.