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31.
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   
32.
M S Jay  C J Graham  C Flowers 《Adolescence》1989,24(94):467-472
This study profiles the characteristics of adolescent suicide attempters and the treatment they received in a pediatric emergency room (ER). A retrospective chart review of 4,072 adolescents seen in the ER at a children's hospital (CH) from July 1984 to June 1985 was undertaken. Twenty-seven adolescents who had deliberately injured themselves were identified. The average age was 14 years 7 months (range 11-19 years). Fifty-two percent of the patients were white and 78% were female. Ingestion was the most common method (78%), followed by attempted hanging (11%), and wrist laceration (7%). After evaluation by a pediatrician in the ER, 30% of the patients were treated and released, 11% were transferred directly to a psychiatric hospital, and 59% were admitted to the CH, with an average hospital stay of 1.88 days. Once hospitalized, consultations from psychiatry (81%), social service (50%), psychology (19%), and neurology (6%) were obtained. At the time of discharge from either the ER or CH, the patients had a variety of plans for ongoing care, with 52% being referred to outpatient counseling, 37% being transferred to a psychiatric hospital, and 11% having no documented plan for ongoing care. These results demonstrate that the evaluation of suicidal adolescents cared for in a pediatric facility may be episodic and suggest the need for a comprehensive program to approach the problem.  相似文献   
33.
The relationship between interpersonal behaviour variables has been shown to be defined by a circular ordering, or circumplex, within the framework of a two-dimensional space. It is proposed that Cleckley's criteria of psychopathy represent one axis of this system, hostility vs warmth. It is also proposed that these criteria alone are not sufficient to identify a homogeneous group of deviant persons. Observer ratings of the behaviour of institutionalized mentally-disordered offenders were obtained for Cleckley's criteria and for behavioural dimensions of impulsive aggression and sociability. Cleckley's criteria were found to describe a unitary dimension whose relationship to other variables was consistent with the circumplex model. Cluster analysis of the ratings identified two distinct groups of high scorers on Cleckey's criteria, who were also significantly differentiated by self-report personality variables. Only one of these groups showed the combination of lack of warmth or affection and lack of behavioural control which several investigators consider necessary to define psychopathy. Relationships among individual rating items and some of the personality variables closely approximated the expected circular ordering. Reference to this interpersonal circumplex appears to reconcile some of the differences in current conceptualizations of psychopathic personality.  相似文献   
34.
While many studies have attempted to produce hypertension through the use of various environmental Stressors, few have succeeded in producing chronic elevations in blood pressure beyond levels considered to be borderline hypertensive (140–160 mm Hg systolic). The problem with most studies stems from the use of genetically normotensive animals and the selection of Stressors to which animals readily adapt. A new approach is suggested, which recognizes the role of genetics in human essential hypertension. Animals with one hypertensive parent do not develop spontaneous hypertension but show a more sensitive cardiovascular response to environmental Stressors than animals with normotensive parents. Preliminary studies revealed that animals with a mixed genetic history of hypertension develop spontaneous borderline hypertension. When subjected to shock-shock conflict, these borderline hypertensive rats (BHR) developed permanent hypertension that failed to abate even after a ten-week, shock-free recovery period. The hypertension was accompanied by elevated heart weight to body weight ratios and by significant cardiac pathology. Subsequent work has demonstrated that these animals also become hypertensive when fed a high-sodium diet. Finally, in a series of exercise studies, we found that BHRs subjected to a shock stressor were protected against stress-induced hypertension if they exercised daily. The potential of this model for studies of the mechanisms by which environmental variables produce permanent hypertension is discussed.  相似文献   
35.
The development and psychometric investigation of the Perceived Support Network Inventory (PSNI), a measure of perceived social support, is described. A group of 146 introductory psychology students participated in a test-retest study design that collected reliability, internal consistency, and construct, convergent, and discriminant validity data on the scale. In addition, a contrast group of 28 Counseling Center clients was administered the PSNI. Test-retest reliability of the PSNI total score and subscale scores ranged from .72 to .88. Internal consistency for the PSNI was .77. Construct validity estimates ranged from .21 to .57. Convergent validity estimates varied from -.25 to .20. Discriminant validity estimates varied from -.11 to .19. Sample differences between introductory psychology student mean PSNI total and subscale scores and Counseling Center client mean PSNI total and subscale scores proved significant. Recommendations for subsequent research and future application are offered.  相似文献   
36.
It is argued that knowing-how (to perform) is not dependent on knowing that (knowing propositions about performance). Existing evidence allows any benefits from metacognitive training to be attributed to generalization training, not to the announcement of rules. Rules may encourage the subject to learn new tasks, but these tasks must be learned in the contexts of eventual application.  相似文献   
37.
In laboratory rats (as in humans) a low-intensity tone that precedes a high-intensity burst of noise by approximately 100 ms can reduce the amplitude of the startle reaction elicited by the burst of noise. A series of four experiments with rats investigated the relation between the inhibitory effects of tonal frequency change and the length of the silent period (gap) preceding it. The major findings were the following: (a) A gap in an otherwise continuous pure tone inhibited startle when the gap occurred approximately 100 ms prior to the noise burst. (b) Although an increase in gap duration increased the inhibition afforded by the gap, the maximum inhibition was yielded by gaps of 100 ms and greater; this maximum was equivalent to the inhibition yielded by the presentation of a postgap tone alone. (c) A shift in tonal frequency across a 10-ms gap yielded more inhibition than did the same gap with no frequency shift; again the shift yielded equivalent inhibition to the presentation of the postgap tone alone. (d) An increase in the frequency shift increased inhibition when the shift occurred across a 10-ms gap, but not when the shift occurred across a 100-ms gap.  相似文献   
38.
During October and November of 1983, three subsamples were selected from three schools in Mesa, Arizona: 34 students in 6th grade, 34 students in 8th grade, and 34 students in 10th grade. A battery of Piagetian-type tasks were individually and randomly administered to each subject. Seven tasks examined projective spatial conceptual abilities, and three tasks examined Euclidean abilities. The same battery of tasks was again administered to the same subjects during November and December of 1984 when all the subjects were in the next grade, that is, 7th, 9th, and 11th. Because of attrition, the number of students tested during the second year were 33, 30, and 28, respectively. To test for significant differences between grade levels, a chi-square one-sample procedure was used. Out of a possible 50 tasks, significant differences were detected in 36 (72%). Those findings, along with an examination of the percentage of students passing each task, support the notion of sequential development of spatial conceptual abilities.  相似文献   
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