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201.
Rats were trained in a three-alternative spatial delayed matching-to-sample task in a starburst maze. Samples consisted of rewarded forced choices of one arm, and retention was indicated by rats’ returning to that arm after a 90-sec delay. If a rat made an error on its first choice, it was returned to the start compartment and allowed a second choice. Unlike in previous experiments with this task, all three arms were available during the animals’ second choices. The rats tended to perseverate in their second choices by returning to the arm that they had erroneously visited on their first choice. In Experiment 1, the accuracy of second choices following first-choice errors was below chance during the first block of sessions, when a 90-sec delay intervened between the first choice and the second choice, and at chance during the second block of sessions, when a short (5–6 see) delay intervened between first and second choices. In Experiment 2, long-delay and short-delay sessions were randomly presented to naive subjects. Similar results were obtained. In both experiments, the tendency to repeat the erroneous first choice was greater when long delays separated the two choices than when short delays were used. The results suggest that rats make their first-choice errors because they erroneously encode or remember the location of the sample and that they base their second choices on the same erroneous-memory. The increase in perseveration at long delays implies some kind of rehearsal-like mechanism that slows forgetting of the memory controlling the first choice. 相似文献
202.
About 16,000 babies each year will be identified with hearing loss by age 3 months once universal newborn hearing screening becomes a reality. Identification of hearing loss in infancy, followed by appropriate intervention by age 6 months, can result in normal language development, regardless of degree of hearing loss. As the average age of identification of hearing loss moves downward toward 2 months, children with hearing loss will enter the educational system earlier and with language skills commensurate with those of their hearing peers. In order to provide appropriate services to children with hearing loss and their families, early interventionists will need to forge links to health care providers involved in universal newborn hearing screening programs, to have specialized training in deafness and hearing loss, and to have expertise in providing services to very young children and to children with hearing loss in the broad range from mild to profound. 相似文献
203.
Veronique M. Boscart Lynn McCleary Paul Stolee Linda Sheiban Taucar Jessica Wilhelm Keia Johnson 《Educational gerontology》2020,46(8):461-472
ABSTRACT Nursing Assistants (NAs) are the largest workforce in nursing homes, but often lack adequate preparation for their role. The Living Classroom (LC) is an integrated learning approach, whereby a NA program is delivered in a nursing home (NH) in collaboration with a community college. This paper describes the implementation and evaluation of the LC. Mixed methods were used to gather data from 48 NA students, 5 faculty, and 42 NH staff over 30 weeks. Students, faculty, and nursing home staff described the LC as a positive learning experience. Students’ gerontological knowledge increased over time (p = .0012). Students reported very positive relationships with program mentors and NH residents. The LC provides a unique approach to prepare NAs to work in nursing homes. This model could expand to other educational programs with a gerontology focus. 相似文献
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Rats were exposed twice in a rotated sequence to a series of six mazes, consisting of hexagonal alleys, balanced for different alley length and structural complexity. Locomotor activity increased with alley length and decreased with structural complexity of the mazes. Locomotion became less stereotyped with increased experience, showing an increasing number of turns, less constant velocity, loss of the initial preference for outward leading alleys and weakening of the forward tendency at reentry from side alleys into hexagonal alleys. In contrast to these qualitative changes of locomotion, the amount of activity remained almost unchanged throughout the experiment. The results suggest that these increases in locomotion complexity depend upon complex interactions between experience and stimulus content of the mazes. 相似文献
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The paper describes the design and use of a studio system which arose out of the need to give demonstrations of experimental procedures to practical classes of up to 150 students. Since the requirements could be specified in some detail it was possible to use novel methods of working which turned out to be very efficient and economical. 相似文献
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