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31.
The effectiveness of a 5-s constant time-delay procedure to teach three chained food preparation behaviors to four moderately retarded adolescent students was evaluated within a multiple probe design across behaviors. Results indicate that the procedure was effective in teaching all four students to make a sandwich, boil a boil-in-bag item, and bake canned biscuits. The skills maintained with at least 85% accuracy over a 3-month period. Training generalized from the school to the home setting for the 2 subjects that completed generalization probe sessions. The percentage of errors across all skills and students was less than 9%.  相似文献   
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Six-hundred and thirteen girls and 601 boys in Zimbabwe completed the Junior Eysenck Personality Questionnaire (JEPQ). The reliability of the Neuroticism (N) and Social Desirability (L) factors was acceptable but the Psychoticism (P) and Extraversion (E) factors possessed modest reliability. While the factorial validity of the P, N and L scales was acceptable, the factorial validity of the E scale was poor. L scores were significantly correlated with N and P scores among girls and boys. Whereas Zimbabwean girls reported higher P scores than did Canadian girls, Zimbabwean boys reported lower P scores than did Canadian boys. Zimbabwean girls and boys reported lower E and N and higher P scores than their Canadian counterparts. This study provides broad support for Eysenck's basic personality model, but it does not support the use of this version of the JEPQ, and especially the E scale, among Zimbabwean children.  相似文献   
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The influences of sex, age, and conversational, partner (mother vs. stranger) on eye contact during verbalizations were examined in a longitudinal study of 33 children at 2 and 4 years of age. A free-play sample was obtained of each child interacting with mother and with a male or female experimenter. The amount of eye contact in conjunction with verbalization was analyzed. Significant main effects were found for sex (females engaged in a higher percent of eye contact than males) and conversational partner (more eye contact while speaking exhibited to experimenter than to mother). There was an interaction between age and conversational partner, in that mother received more and experimenter relatively less percent of eye contact during verbalizations as children got older. Notably, there was no main effect for age. These results revealed sex differences at an age (2–2 1/2 years) and in a context (free-play setting) not previously studied, demonstrating the robustness of the effect. Further, age findings seem indicative of unique developmental trends for eye contact during verbalizations for the ages between 2 and 4 years.Mount Saint Vicent University  相似文献   
37.
Orientation discrimination and cortical function in the human newborn   总被引:1,自引:0,他引:1  
A Slater  V Morison  M Somers 《Perception》1988,17(5):597-602
There is some controversy concerning whether or not the visual abilities of the newborn are mediated entirely through subcortical pathways or whether the visual cortex is functioning at birth. A critical test of cortical functioning is discrimination of orientation: orientation-selective neurons are found in the visual cortex but not in subcortical parts of the visual system. An experiment is described in which newborn infants were habituated to a square-wave grating oriented 45 degrees from vertical. After habituation, significant preferences for the novel, mirror-image, grating were found, a result which argues for some degree of visual cortical functioning at birth.  相似文献   
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Iconic memory, which was initially regarded as a unitary phenomenon, has since been subdivided into several components. In the present work we examined the joint effects of two such components (visible persistence and the visual analog representation) on performance in a partial report task. The display consisted of 15 alphabetic characters arranged around the perimeter of an imaginary circle on the face of an oscilloscope. The observer named the character singled out by a bar-probe. Two factors were varied: exposure duration of the array (10, 50, 100, 150, 200, 300, 400 or 500 ms) and duration of blank period (interstimulus interval, ISI) between the termination of the array and the onset of the probe (0, 50, 100, 150, or 200 ms). Performance was progressively impaired as both exposure duration and ISI were increased. The results were explained in terms of a probabilistic combinatorial model in which the timecourses of visible persistence and of the visual analog representation are regarded as time-locked to the onset and to the end of stimulation, respectively. The impairing effect of exposure duration was attributed to the relatively high spatial demands of the task that could be met optimally by information in visible persistence (which declines as a function of exposure duration), but less adequately by information in the visual analog representation. A second experiment, employing a task with lesser spatial demands, confirmed this interpretation.  相似文献   
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Previous theories of intrinsic motivation have traditionally ignored the experiential or subjective aspects of engagement in intrinsically and extrinsically motivated tasks. Part of the reason for the lack of research in this area was our ignorance of which emotions to study. Data are presented here from two studies designed to produce the first systematic evidence of changes in basic emotional states during task engagement. Our findings suggest that intrinsic and extrinsic tasks can be differentiated according to the emotional changes subjects retrospectively report about their engagement with these tasks, and point the way to future research incorporating emotion as an important variable to consider.The first author was supported in part by a Minority Fellowship administered by the American Psychological Association under a Clinical Training Grant from the National Institute of Mental Health (5 T01 MH13833), and by a Regents Fellowship from the University of California, Berkeley.  相似文献   
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