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911.
In Experiment 1 six monkeys were tested with discriminative relations that were backward relative to their training in a 0-second conditional (“symbolic”) matching procedure. Although there was some indication of backward associations, the evidence was generally weak, and statistical evaluations did not reach conventional significance levels. Unlike children, who show backward associations to the point of symmetry, monkeys and pigeons display at best only weak and transient backward associations. In Experiment 2 associative transitivity was assessed across two sets of conditional matching tasks. All four monkeys tested demonstrated strong transitivity. In contrast, in Experiment 3 there was no evidence of transitivity in three pigeons tested under conditions closely comparable to those of Experiment 2. These results may identify some key features of interspecies differences and contribute to analyses of serial learning in animals.  相似文献   
912.
Flicker fusion frequencies of 48 healthy controls and of 35 alcoholics were measured to detect possible associations between flicker fusion and signs of nonspecific brain damage, the aim of the study. FFF was statistically significantly lower in patients addicted to alcohol than in healthy subjects. Lower flicker fusion frequencies were associated with the severeness of organic psychosis as rated psychopathologically. The hypothesis that addiction to alcohol is a sign of diffuse, nonspecific, organic brain damage was discussed.  相似文献   
913.
Locomotor activity of male, albino rats (25, 90, and 200 days old at the start of the experiment) was measured in conditions of light and dark. Continuous and pulsed noises of 50, 60, 70, 80 and 90 dB were presented under each illumination condition. While noise intensity altered activity of all age groups, it interacted with illumination and age, resulting in different sensory-dependent patterns of activity in each age group. The results are interpreted in terms of arousal theory and potential functional development of CNS structures regulating the effects of ambient sensory input on behavior.  相似文献   
914.
Correlations were calculated between the Token Test of Language Development (Token) and scores of the Wechsler Intelligence Scale for Children--Revised (WISC-R) based on responses from 38 Caucasian children (23 boys and 15 girls) of a semi-rural Northeastern Ohio school district. The relatively low Pearson correlations (.25 to .47) between the standard scores in the Token test and WISC-R IQs are discussed in relation to ability and achievement.  相似文献   
915.
The Safety Locus of Control Scale was designed to predict employees' accidents and injuries. Internal scorers think they should assume personal responsibility for their safety, and they believe they can take preventive steps to avoid accidents. External scorers assume little personal responsibility for prevention of accidents. Instead, they place more blame on factors outside their control, such as luck or chance. This study showed that the safety scale was effective in differentiating between groups with varying accident histories, which supports the criterion-related validity of the scale.  相似文献   
916.
Plasma concentrations of imipramine and amitriptyline and their desmethylated metabolites were measured in 20 children being treated for major depressive illness 2 wk. and 5 to 10 wk. after achieving drug dosages of 2.25 mg/kg body weight. At 2 wk. all children had exhibited clinical improvement, but by 10 wk. 4 of the 10 children treated with imipramine and 5 of the 10 children treated with amitriptyline had experienced clinical relapse of depressive symptoms. Tricyclic antidepressant plasma concentrations and ratios were comparable in the subgroups of children who maintained their clinical improvement and those who relapsed. There was no evidence of a systematic decline in plasma tricyclic antidepressant concentrations in those children who relapsed.  相似文献   
917.
The subjects were 16 college students assessed as having normal, uncorrected visual abilities. Each subject responded to the appearance of each of five variously colored ball sections as they were introduced into the subjects' visual field. Analysis indicated that colors with luminance values greater than 70 CD/M2 (black, blue, green) were detected further in the horizontal peripheral plane than were colors possessing values less than 36 CD/M2 (red, purple).  相似文献   
918.
Subjects in a prior study of complex learning often experienced difficulty in mastering the task because of an apparent reluctance to release one perceptual field and reconstrue the task on a higher cognitive level. It was hypothesized that were this the correct explanation, the faster learners would be more field independent on a measure of field dependence, since independence has been defined in terms of ease in releasing one's attention from the immediate perceptual field. This hypothesis was tested with 22 undergraduate subjects for whom Group Embedded Figures Test scores were correlated with the number of trials to completion on the complex learning task. A moderate but significant correlation supported the hypothesis.  相似文献   
919.
A property of attitudes, namely, the fact that attitudes select facts, is used to comment upon a paper on handedness and career choice.  相似文献   
920.
Effects of presentation complexity on rapid-sequential reading   总被引:1,自引:0,他引:1  
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