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941.
The effects of salience on 4- and 6-year-old children's ability to classify multiplicatively was investigated. A rank-ordered salience hierachy consisting of 3 dimensions was first assessed for each S. Several weeks later half the Ss of each age group were presented with a series of 9 3 times 3 matrix problems consisting of values from 2 dimensions ranked high in salience. The remaining half received identically structured matrices consisting of values from 1 highly salient dimension and of others from a dimension ranked low in salience. The goal in each problem was to select that compound stimulus from a set of alternatives that appropriately filled an empty cell in the matrix. Prior to the matrix problems, half the Ss in each matrix condition received sensitization training designed to increase the salience of the relevant dimensions in the matrix problems. The results showed that the pre-assessed salience of the relevant dimensions affected matrix solution in that more accurate performance was associated with those problems with both relevant dimensions relatively high in salience than those with one high and one low. Although the older Ss solved more problems, the evidence for coordination in the younger Ss was clear. No effects of sensitization training were found. 相似文献
942.
943.
To study sensitivity to radial location of an odor source, 20 human newborns, ranging from 16 to 130 hours of age, were presented with a small amount of ammonium hydroxide. The odor source was placed near the nose slightly to the left or right of midline, with its position randomized over repeated trails. Direction of headturn with respect to the odor location and diffuse motor activity were scored from the videotape recordings of the newborns' behavior. It was found that as a group, the newborns turned away from the odor source more frequently than they turned toward it. The tendency to turn away from the odor was stronger in infants who displayed less motor activity after the response. Newborns also exhibited a right bias in the direction of the head movements. It is concluded that a spatially appropriate avoidance response is present in the neonate and that the newborn is innately sensitive to the radial location of an odor. 相似文献
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947.
Interaction and learning: Theorizing on the art of teaching 总被引:1,自引:0,他引:1
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950.
Mechanisms of the relation between perinatal problems, early childhood illness, and psychopathology in late childhood and adolescence 总被引:6,自引:0,他引:6
Data on perinatal and early childhood somatic and psychological risk factors of a random sample of children were gathered in early to middle childhood and employed to examine the long-term risk of emotional and behavioral problems of late childhood and adolescence. 3 issues were addressed: First, can syndromic specificity of such effects be identified on scaled and diagnostic measures of syndromes? Second, are these effects attributable to excess risk of low-income children for both perinatal and later childhood problems? Third, are the intervening mechanisms identifiable as intellectual impairment, vulnerability to poor health, poor maternal caretaking, maternal rejection, or maternal stress associated with marital problems? Findings indicated that elevated risk was present for all syndromes, both at the scale level and at the diagnostic level. None of the examined intervening mechanisms fully accounted for the effects of early risks. 相似文献