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41.
A running-wheel-movement-detection system is described for use with an IBM-compatible system and a serial mouse. It is an adaptation of a system developed for use on a Commodore 64. The IBM-compatible system provides obvious advantages in speed, memory, data storage, and programming ease over the earlier Commodore 64 system.  相似文献   
42.
Two experiments addressed the influences of harmonic relations, melody location, and relative frequency height on the perceptual organization of multivoiced music. In Experiment 1, listeners detected pitch changes in multivoiced piano music. Harmonically related pitch changes and those in the middle-frequency range were least noticeable. All pitch changes were noticeable in the high-frequency voice containing the melody (the most important voice), suggesting that melody can dominate harmonic relations. However, the presence of upper partials in the piano timbre used may have accounted for the harmonic effects. Experiment 2 employed pure sine tones, and replicated the effects of Experiment 1. In addition, the influence of the high-frequency melody on the noticeability of harmonically related pitches was lessened by the presence of a second melody. These findings suggest that harmonic, melodic, and relative frequency height relationships among voices interact in the perceptual organization of multivoiced music.  相似文献   
43.
Changeover behavior and preference in concurrent schedules   总被引:2,自引:2,他引:0       下载免费PDF全文
Pigeons were trained on a multiple schedule of reinforcement in which separate concurrent schedules occurred in each of two components. Key pecking was reinforced with milo. During one component, a variable-interval 40-s schedule was concurrent with a variable-interval 20-s schedule; during the other component, a variable-interval 40-s schedule was concurrent with a variable-interval 80-s schedule. During probe tests, the stimuli correlated with the two variable-interval 40-s schedules were presented simultaneously to assess preference, measured by the relative response rates to the two stimuli. In Experiment 1, the concurrently available variable-interval 20-s schedule operated normally; that is, reinforcer availability was not signaled. Following this baseline training, relative response rate during the probes favored the variable-interval 40-s alternative that had been paired with the lower valued schedule (i.e., with the variable-interval 80-s schedule). In Experiment 2, a signal for reinforcer availability was added to the high-value alternative (i.e., to the variable-interval 20-s schedule), thus reducing the rate of key pecking maintained by that schedule but leaving the reinforcement rate unchanged. Following that baseline training, relative response rates during probes favored the variable-interval 40-s alternative that had been paired with the higher valued schedule. The reversal in the pattern of preference implies that the pattern of changeover behavior established during training, and not reinforcement rate, determined the preference patterns obtained on the probe tests.  相似文献   
44.
We studied the course of aggressive behavior in an epidemiologically defined sample of first graders with and without comorbid anxious symptoms. Our primary purpose in doing so was to understand whether the stability of aggression in young children was attenuated or strengthened in the presence of comorbid anxiety. Previous studies of older children and adolescents had produced equivocal findings in this regard. Data on anxious symptoms were obtained through an interview of the children, whereas aggressive behavior was assessed through the use of a teacher interview and peer nominations. Assessments were performed in the fall and spring of first grade. In contrast to children classified as aggressive alone in the fall of first grade, boys and girls classified as aggressive and anxious in the fall of first grade were significantly more likely to be classified as aggressive in the spring in terms of teacher ratings and/or peer nominations of aggression. Thus our findings suggest that the link between early and later aggression may be strengthened in the presence of comorbid anxious symptoms, rather than attenuated. Future studies are needed to identify the mechanisms by which the course of aggression is influenced by the presence of comorbid anxiety.The writing of this paper was supported by the following National Institute of Mental Health grants: Epidemiologic Prevention Center for Early Risk Behavior (P50 MH38725); Periodic Outcome of Two Preventive Trials (1RO1 MH42968). The authors would like to thank the Baltimore Public City School System and the children and parents who participated in this study.  相似文献   
45.
A 15-year-old-boy was referred on account of a fluency disorder that was not thought to be stuttering. The problems of the lack of an adequate definition of cluttering are discussed along with the inherent problems of providing a wide-based assessment of this client group. Assessments were conducted on the motoric, linguistic, and intellectual abilities of this client, and the findings are discussed.  相似文献   
46.
This study tested predictions concerning the associations between children's nonparental care experiences and emotion regulation. It involved 53 participants (21 girls and 32 boys) of preschool age and their mothers. The children's care experiences ranged from those who were raised exclusively at home to those who had nonparental care experience beginning in early infancy. The participants were observed in a laboratory playroom, and their mothers were asked to complete questionnaires regarding their children's care histories and their current care situations. The children with extensive nonparental care backgrounds were found to be more likely to use self-directed emotion regulation behaviors when faced with a mildly frustrating situation. In the same situation, the children who had experienced minimal nonparental care were found to be more likely to use other-directed emotion regulation behaviors. Additionally, the children who had experienced care settings with large numbers of children in each care group or who had experienced many caregiver changes were more likely to use self-directed emotion regulation behaviors, whereas those who had experienced settings with smaller care groups and fewer caregiver changes were more likely to use other-directed emotion regulation behaviors.  相似文献   
47.
This study compared the effectiveness and efficiency of simultaneous prompting with and without error correction during daily probe sessions in teaching science vocabulary words. The teacher presented the vocabulary word definitions as instructive feedback during training sessions. Five 16–17 year old students with disabilities participated in an adapted alternating treatments design that evaluated the simultaneous prompting strategy, error correction and instructive feedback. Instruction occurred in a group format using choral responding. The results indicate that (a) all students learned to read the vocabulary words, (b) simultaneous prompting with error correction was slightly more efficient for three of the five subjects in learning the targeted words, and four of the five students made fewer errors in this condition, (c) all students preferred simultaneous prompting with error correction over simultaneous prompting without error correction, (d) words mastered in both conditions generalized equally, (e) there were minimal differences between the two conditions in the collected maintenance data, and (e) students experienced only minimal improvement in their ability to define vocabulary words (instructive feedback). Discussion focuses on issues for further research and implications for instructional practice with simultaneous prompting, error correction and instructive feedback.  相似文献   
48.
49.
In two experiments, the pattern of persistence of negative priming effects across delay intervals of 500 and 2,500 msec was assessed using a within-subjects, random sequencing of delays. Neill and Valdes (1992; Neill, Valdes, Terry, & Gorfein, 1992) have argued that a within-subject experimental design is required for decay of negative priming to be seen, in contrast to results reported elsewhere (e.g., Tipper, Weaver, Cameron, Brehaut, & Bastedo, 1991) showing stable negative priming effects across delays. In neither experiment was substantial evidence of decay detected, raising questions for the notion that suppression necessarily declines across brief temporal intervals and for the assertion that episodic retrieval is the sole source of negative priming.  相似文献   
50.
Prominence of the brain's right-hemisphere information processing and intensity of dream experience are two theoretically related constructs that have been proposed as important psychological aspects of REM sleep. Either view is consistent with the prediction that the effect of REM deprivation will depend in part on the nature of cognitive activity that is initiated at the onset of each REM period and that "substitutes" for the interrupted REM process. In the present study, the effect of REM deprivation was more striking for female subjects given a digits task than for female subjects given a fantasy-reporting task during awakening used to induce REM deprivation for the first 6 hours of the night. High neuroticism appeared to exaggerate the effect. No corresponding pattern was observed for the male subjects. These preliminary finding may be exaggerated by cognitive activity that is functionally incongruent with those processes. The results also raise interesting questions about individual differences.  相似文献   
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