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991.
This research was concerned with the effects of different classes of cues on the ability of toads (Bufo marinus) to learn an escape task, discrimination learning, in a T-maze. The cues were either a black or white brightness cue, a right or left position cue, or combinations of brightness and position cues. The toads were given a .6-A shock until they made the correct response. Results suggested that toads are capable of learning a discrimination task based on either a position or brightness cue. However, the rate of learning was influenced by strong aversion to the white arm when escaping from an aversive stimulus. No particular preference for either brightness or position cues was found independent of this aversion.  相似文献   
992.
The present studies assessed the degree of stimulus control exerted by S+ and S? without confoundings of stimulus novelty and stimulus ambiguity. In Experiment 1, rats were trained on two intercurrent simultaneous discrimination problems with nine times more training given on one than the other. Then the animals were given transfer tests with re-paired stimuli. The results showed that S? exerts greater stimulus control than S+ in a two-choice simultaneous discrimination. Experiment 2 provided a test of the possibility that the relative degree of control by S? varies with different amounts of training. Three groups were trained on two intercurrent simultaneous discrimination problems; each group was given 7, 11, or 15 times more training on one problem than the other. Then transfer tests were given with re-paired stimuli. Again the results showed that S? exerts greater stimulus control than S+ in a two-choice simultaneous discrimination.  相似文献   
993.
A direct comparison was made of the reliability and validity of the standard Matching Familiar Figures Test (MFF) to a recent longer version of the task (MFF20). Subjects comprised two samples of learning-disabled children, matched on age, sex, IQ, and SES. The Salkind and Wright (1977) formulation was used to generate continuous data, and IQ was statistically controlled. Internal reliability estimates showed the MFF20 to be more consistent that the standard version on both error and latency scores. Validity was addressed by comparing the two versions of the task in their ability to predict cognitive and behavioral skills of conceptual relevance to impulsivity. Results indicated that the MFF20 is a more sensitive predictor of academic achievement and attention as observed in a natural setting than is the standard version of the task.This study was supported by a contract (300-77-0495) from the Bureau of Education for the Handicapped, Office of Education, for the University of Virginia Learning Disabilities Research Institute. The authors would like to express appreciation to the school officials who generously assisted in the present study: Elizabeth Bailey, Thomas Cox, Charles Dempsey, Julian King.  相似文献   
994.
The form of the memory representation for visual patterns consisting of a few line segments was investigated with three tasks. One task was the reproduction of remembered patterns using pencil and paper. The order in which the subparts of those patterns were reproduced was used to make suggestions about possible memory representations for the patterns. The second task involved rating the “goodness” of subparts of the patterns. These ratings were also interpreted as reflecting the underlying representations of the patterns. In the third task, the time required to recognize that a small pattern was part of a larger remembered pattern was used as further evidence about the memory representations of the patterns. The results from all three tasks are consistent with the theory that the memory representations are tree structures. Methods for deriving and comparing tree structures are discussed.  相似文献   
995.
The behavioral symptoms of a population of children with speech and language disorders (with a mean age of approximately 6 years) were studied with a teacher and a parent questionnaire. A factor analysis produced similar factors for both questionnaires: Hyperactivity-Conduct, Affect, and Language. An Asocial factor was also found with the teacher questionnaire. The factors of this study were in good agreement with the general factors of Aggression and Withdrawal found in other quantitative studies. Mean factor score profiles were reported for this unique population of children.The authors would like to thank Dr. Donald Guthrie for his statistical consultation and Dr. Howard Grey for the use of his patient population.  相似文献   
996.
In a study of 105 same-sex twin pairs, ages 7 to 10 years, maternal ratings on 23 bipolar scales yielded six factors designated as compliant morality, applied cognitive, sociability, emotionality, tough-mindedness, and activity-distractibility. Analyses by twin pairs (68 identical, 37 fraternal) indicated that correlations for identical pairs were significantly higher than fraternal pairs on all but one factor: tough-mindedness. Profile analyses for the six factors indicated that the profiles of scores across the factors were more concordant for the identical twin pairs. Correlations obtained from the individual scales produced differences between the identical and fraternal twin pairs as well. Overall, the data suggested that several components and the total organization of those components of personality and temperament are genetically influenced.  相似文献   
997.
Subsequent to success or failure experience, 48 subjects attempted a psychomotor task in order to escape or avoid an aversive stimulus (tone). Their attempts at solving the task over 24 trials were made in the presence of subject-experimenters each of whom had expectancies instilled regarding the solution to the task. The job of the subject-experimenters was to “offer information” on every third trials as the subjects attempted to solve the task. It was hypothesized that the expectancies of the subject-experimenters would be communicated to the subjects via periodic comments, that these expectancies would differentially affect the subjects' performance on the task, and that prior experience on a similar task would differentially affect subjects' performances on the task. The results demonstrated that the expectancies instilled in the subject-experimenters were communicated and influenced the performances of subjects as predicted. It appears that consistency with respect to the expectancies communicated played a major role in producing significant effects. Prior experience failed to produce significant differences on task performance, a finding conflicting with that of D.S. Hiroto (Journal of Experimental Psychology, 1974, 102, 187–193). The results are discussed from the perspective of using the overt, explicit communication of expectancies as a means for exploring the illusive phenomenon of the experimenter expectancy effect.  相似文献   
998.
The generality of the recognition failure phenomenon was the primary basis for the present research. It was hypothesized that the phenomenon obtains whenever an insufficient degree of compatibility exists between the task demands at recognition and those present during study. Experiments 1 and 2 demonstrated that, despite a recognition task that was incompatible to conditions of encoding, subjects could actively reconstruct aspects of the initial situation, and hence recognition failure was minimized. It was assumed that the stimulus material — categorized word pairs — facilitated this reconstructive process. Experiment 3 was designed specifically to examine further the reconstructive process as well as recognition failure. The results indicated that (a) the nature of this process could be mathematically predicted, and (b) subjects seldom failed to recognize words they recalled. The results of the present study strongly suggest an important boundary condition of the phenomenon of recognition failure. Moreover, Tulving and Wiseman's (1975) quadratic function could not predict accurately the obtained magnitude of recognition failure.  相似文献   
999.
1000.
A follow-up was made of the welfare payments received by AFDC clients who had received job-finding counseling. At the 6th-month follow-up, welfare payments had been reduced by about one-half for the Job Club clients vs 15% for the control group.  相似文献   
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