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911.
Researchers interested in studying discrimination learning in primates have typically utilized variations in the Wisconsin General Test Apparatus (WGTA). In the present experiment, a new testing apparatus for the study of primate learning is proposed. In the video-task paradigm, rhesus monkeys (Macaca mulatta) respond to computer-generated stimuli by manipulating a joystick. Using this apparatus, discrimination learning-set data for 2 monkeys were obtained. Performance on Trial 2 exceeded 80% within 200 discrimination learning problems. These data illustrate the utility of the video-task paradigm in comparative research. Additionally, the efficient learning and rich data that were characteristic of this study suggest several advantages of the present testing paradigm over traditional WGTA testing.  相似文献   
912.
Some properties are discussed of regular polygons that may result from angular homeostatic processes in stable orbit. To characterize these homeostatic polygons we need to discuss the winding number, the sidedness (integer, fractional and irrational), multiplicity, envelopes, and density. A regular (i.e., equilateral, equiangular) polygon may be closed in one revolution about its unique center, in multiple revolutions, or not at all. A homeostatic polygon can be generated only if all vertices are included in a single polygon, which occurs if and only if the number of vertices and the number of revolutions required to complete the polygon are relatively prime. For the homeostatic polygon to have a finite number of sides (without repeating itself) the angle subtended by any two successive vertices at the center must be a rational multiple of 2. Biological implications of these properties are illustrated.  相似文献   
913.
914.
In three experiments, musically trained and untrained adults listened to three repetitions of a 5-note melodic sequence followed by a final melody with either the same tune as those preceding it or differing in one position by one semitone. In Experiment 1, ability to recognize the final sequence was examined as a function of redundancy at the levels of musical structurein a sequence, contour complexity of transpositions in a trial, and trial context in a session. Within a sequence, tones were related as the major or augmented triad; within a trial, the four sequences began on successively higher notes (simple macrocontour) or on randomly selected notes (complex macrocontour); and within a session, trials were either blocked (all major or all augmented) or mixed (major and augmented randomly selected). Performance was superior for major melodies, for systematic transpositions within a trial (simple macrocontours), for blocked trials, and for musically trained listeners. In Experiment 2, we examined further the effect of macrocontour. Performance on simple macrocontours exceeded that on complex, and excluded the possibility that repetition of the 20-note sequences provided the entire benefit of systematic transposition in Experiment 1. The effect of musical structure (major/augmented) was also replicated. In Experiment 3, listeners provided structure ratings of ascending 20-note sequences fromExperiment 2. Ratings onsame trials were higher than those on correspondingdifferent trials, in contrast to performance scores for augmentedsame anddifferent trials in previous experiments. The concept of functional uncertainty was proposed to account for recognition difficulties on augmented same trials. The significant effects of redundancy on all the levels examined confirm the utility of the information-processing framework for thestudy of melodic sequence perception.  相似文献   
915.
916.
A sample of physician-referred chronic insomniacs was randomly allocated to either progressive relaxation, stimulus control, paradoxical intention, placebo or no treatment conditions. Treatment process and outcome were investigated in terms of mean and standard deviation (night to night variability) measures of sleep pattern and sleep quality. Only active treatments were associated with significant improvement, but the nature of treatment gains varied. In particular, stimulus control improved sleep pattern, whereas relaxation affected perception of sleep quality. All improvements were maintained at 17 month follow-up. Results are discussed with reference to previous research and guidelines are given for clinical practice.  相似文献   
917.
918.
919.
Affective quality of family relations and adolescent identity exploration   总被引:1,自引:0,他引:1  
D R Papini  R A Sebby  S Clark 《Adolescence》1989,24(94):457-466
The purpose of this study was to examine the relationship between adolescent pubertal status, the affective quality of family relations, and the early adolescent's exploration of a sense of ego identity. Fifty-one intact families with adolescents in the seventh grade agreed to participate. Each family member completed a battery of questionnaires designed to assess familial adaptation to pubertal growth and identity exploration. The results reveal that the affective quality of parent-adolescent relationships and the pubertal status of the adolescent appear to influence the adolescent's exploration of ego identity. The need to establish the functional significance of familial adaptation to adolescent pubertal growth for identity development is discussed.  相似文献   
920.
Material is presented from the case history of a patient whose interest in spelunking (cave exploration) was found to be an unconscious expression of a type of counterclaustrophobia. Both oedipal and preoedipal determinants of the claustrophobic anxieties are delineated. Of particular note in this instance is the testicular element in the genesis of the patient's claustrophobia. His confusion of the movements of his testicles into his inguinal canals during childhood defecation with the movements of the feces themselves lent an special intensity to his fear of being flushed away from the mother by an expulsive anal birth from the claustrum. Childhood anxiety aroused when his testicles would become trapped in the inguinal canals was an important forerunner of the adult fear of being trapped in confined spaces. A counterphobic element of the spelunking per se was his enjoyment in hanging suspended by a rope in caves. In this manner, he was able to act out (by virtue of his body-testicle equation) his identification with, and control over, the disappearing testicles in the setting of a claustrophilic union with the mother.  相似文献   
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