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To examine the developmental significance of mirrow self-recognition in early childhood, a cross-sectional study with 55 Down's syndrome children was conducted. When their image is altered by rouge on the nose, normal infants by 22 months indicate self-recognition by touching their noses while looking in the mirror. Only a small percentage of Down's syndrome children touched their noses by this age, confirming the expected lag in this development. However, those young Down's syndrome infants with near-normal development quotient did manifest the reaction. In general, when developmental age was equated, the Down's syndrome children showed parallel development to normal children. 相似文献
95.
In an attempt to clarify the chronological relationship between identity and equivalence conservation, normal preschool-aged children (experiment 1) were exposed to brief videotape demonstrations of a model conserving identity and equivalence, identity only, equivalence only, or neither. Subsequent performances indicate that identity was easier to accelerate than equivalence, and training in both identity and equivalence appeared to be most effective in accelerating conservation. Trainable mentally retarded (TMR) children were then exposed to either the identity-equivalence-conserving or control model (experiment 2). This population, which some have argued remains at a preoperational level of functioning, was more likely to conserve identity than equivalence. In addition, conservation in the training group increased following training, though these gains were not maintained over a 3-week retention interval. 相似文献
96.
First-grade males performed a 30-min visual vigilance task under 5 conditions of auditory background stimulation. The 5 conditions consisted of (1) continuous conversation, in which subjects listened to a tape of conversation spliced so that there were no intervals of silence lasting longer than 3 sec; (2) continuous reverse, in which subjects heard the continuous conversation tape played in reverse; (3) intermittent conversation, in which subjects heard alternating segments of conversation and silence; (4) intermittent reverse, in which subjects heard alternating segments of reverse conversation and silence; and (5) silence control. Compared with silence or continuous stimulation, intermittent stimulation produced better detection regardless of whether or not it was meaningful. High achievers made more correct detections than low achievers, but only in the second and third time periods. Few subjects made errors of commission. 相似文献
97.
Victor D Hopper 《Endeavour》1978,2(3):121-126
Measurement of vertical and horizontal wind velocity is of great importance in many contexts, such as investigation of air pollution, weather forecasting, and air-traffic control. In recent years continuously recording acoustic sounders have been developed which give reliable results at reasonable cost: some 200 are now in use in at least 15 countries. 相似文献
98.
D P Biklen 《American annals of the deaf》1975,120(4):382-386
99.
Georges D. Szakasits 《Research Policy》1974,3(1):18-28
The article deals with the results achieved by the adoption of the SAPPHO method (developed by the Science Policy Research Unit of Sussex University) to the conditions of the Hungarian electronics industry. The results coincide to a great extent with those established in the course of the survey made in England, although there are some significant differences. 相似文献
100.