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31.
A model of childhood hyperkinesis, using the Telomian-beagle hybrid dog, is described, demonstrating the interactions of genetics and separation in the development of this syndrome and in the favorable responses of some of these dogs to amphetamine. This work represents the collaboration of three laboratories, utilizing chiefly methods of inhibitory training. Inducing separation distress enhanced the resistance to inhibitory training and the favorable responses to amphetamine.  相似文献   
32.
The discrimination learning of the /r/ and /l/ sounds in a single 1-h session by Japanese college students who had received little or no English conversation training was examined. About half of the subjects exhibited significant improvement after this brief amount of training. A three-state Markov model with the unconditioned, intermediate, and conditioned states was applied as a first approximation of the learning of the liquid pairs, learning which is characterized as two-stage all-or-none conditioning. Also found in the study was a significant correlation between the ability to perceive the liquids and the ability to read English as assessed by a cloze procedure. This correlation is interreted in light of general theory on phoneme awareness.  相似文献   
33.
An account ofsame-different discriminations that is based upon a continuous-flow model of visual information processing (C. W. Eriksen & Schultz, 1979) and response competition and inhibition between the responses by which the subject signifies his judgment is presented. We show that a response signifyingsame will on the average be executed faster due to less priming or incipient activation of the competing response,different. In the experiment, the subjects matched letters on the basis of physical identity. The degree of priming ofdifferent responses on same trials and ofsame responses ondifferent trials was manipulated by an extraneous noise letter placed in the display. Latency for judgments onsame trials increased as the feature overlap of noise and target letters decreased. Latencies were shorter ondifferent trials when the noise letter was dissimilar to either target letter than when the noise letter was the same as one of the targets. These results were consistent with the response-competition interpretation.  相似文献   
34.
35.
When head-movement parallax functioned as the sole veridical distance cue during exposure to spectacles that altered the eyes’ oculomotor adjustments, sizable adaptation was obtained. This result showed that a discrimination of the distances of 60 and 30 cm can be based on head-movement parallax. Using adaptation in demonstrating that head-movement parallax can serve as a distance cue circumvents the problem that the presence of accommodation normally presents when such a demonstration is attempted. The usual contamination of head-movement parallax with accommodation is avoided, because accommodation is altered by the spectacles and does pot function as a veridical cue along with head-movement parallax.  相似文献   
36.
In Experiment 1, it is shown that during reading the eye makes larger saccades near long words than near short words. The effects are reduced when the subject’s peripheral vision is diminished by the use of a moving “window” centered on the subject’s fixation point, outside of which letters are replaced by Xs. In Experiment 2, it is shown that even if linguistic predictions are kept constant, the eye tends to make longer jumps when approaching THE than when approaching a three-letter verb. This “THE-skipping” effect is weaker if THE is compared with an auxiliary (HAD, WAS, or ARE) than if it is compared with a less frequently occurring verb (ATE, RAN, MET). It follows that knowledge of the lexicon can combine with information from peripheral vision fast enough to influence saccade size from moment to moment.  相似文献   
37.
The experiment was designed to test differential predictions derived from dual-coding and depth-of-processing hypotheses. Subjects under incidental memory instructions free recalled a list of 36 test events, each presented twice. Within the list, an equal number of events were assigned to structural, phonemic, and semantic processing conditions. Separate groups of subjects were tested with a list of pictures, concrete words, or abstract words. Results indicated that retention of concrete words increased as a direct function of the processing-task variable (structural < phonemic 相似文献   
38.
When temporal auditory acuity is estimated using time-reversed click pairs, the asymmetry of temporal masking may influence the results. To investigate this hypothesis, we first established normal-hearing listeners’ psychometric functions for the discrimination of time-reversed click pairs. An attempt to relate listeners’ performances in click-pair discrimination to their performances in forward and backward masking tasks was unsuccessful, probably due to the presence of spectral artifact in the temporal masking paradigms. We then investigated listeners’ abilities to discriminate time-reversed click pairs in which the intensity of the lower level click in one pair was altered. This alteration was introduced at random in order to minimize the influence of spectral artifact. Our results suggest that the course of temporal masking influenced the discriminability of the modified click pairs. Thus, the discrimination of time-reversed click pairs may yield a biased estimate of auditory temporal acuity.  相似文献   
39.
Eight volunteers maintained on daily methadone participated in a classical conditioning procedure to determine which if any of the elements of narcotic withdrawal could be conditioned. The unconditioned stimulus was the injection of a small dose of naloxone. The unconditioned response was a brief precipitated withdrawal syndrome. The conditioning stimulus was a tone, odor, and injection of saline. Conditioning was successful in the pilot study in 5 of 8 subjects. The conditioned response consisted of tearing, yawning, lacrimation, systolic blood pressure increase, respiratory irregularities and subjective feelings of narcotic withdrawal sickness (nausea, muscle aches, chills). A second group of 8 subjects showed, in addition to the above, evidence of conditioning of heart rate, respiratory rate and skin temperature decrease. These laboratory findings support the clinical reports of a conditioned withdrawal syndrome and suggest ways to improve treatment results by detecting and extinguishing or modifying conditioned responses.  相似文献   
40.
大学生的成就动机和成功恐惧研究   总被引:36,自引:0,他引:36  
运用成就动机问卷和投射测验研究了大学生的成就动机和成功恐惧。结果表明 ,大学生的成功恐惧有四种 ,分别与人际、家庭、学业和事业有关。由投射测验引起的成功恐惧有明显的性别差异和专业差异。成就动机、追求成功的动机与成功恐惧负相关显著 ,避免失败的动机与成功恐惧正相关显著。  相似文献   
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