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31.
Human fetal cardiac responses (36-39 weeks gestational age) to brief, repeated vocal stimuli (male or female voice uttering the same sentence), given at 90-95 dB SPL ex utero (around 20-30 dB less in utero) during a state of low fetal heart rate (FHR) variability, were examined using highly conservative statistical criteria taking into account each subject's prestimulus FHR variability. Subjects exposed to either of the two stimuli displayed significantly more decelerative heart rate (HR) changes compared to control subjects receiving no stimulation. The decelerative changes started during the first seconds following the onset of stimulation and reached their amplitude peak within 10 or 20 sec, depending on the subject. The directions—HR acceleration or deceleration—and the amplitude of the response depended on prestimulus HR variability only, not on prestimulus level. No major difference was found between the effects of the two voices. The data are compared to previous studies demonstrating fetal decelerative changes to acoustic stimuli of less than 105 dB SPL. The choice of an objective criterion to define an HR response and the possible orienting response nature of the decelerative change are discussed.  相似文献   
32.
Teams are playing an increasingly important role in the workplace. However, reviews of the team performance literature have suggested that there are serious deficiencies in our understanding of team processes and performance (e.g., Dyer, 1984). These difficulties may be attributable, in part, to the lack of laboratory methodologies to investigate team performance. This paper describes the use of low-fidelity simulations as a potentially useful paradigm for researching team coordination and performance. This paradigm is advantageous in that it offers relatively high levels of experimental control and task representation at a low cost.  相似文献   
33.
Little research has been conducted on Loevinger's Washington University Sentence Completion Test of Ego Development in adult psychiatric outpatients. The measure is a promising method of assessing a construct of personality and character functioning that should be useful in research on psychopathology and in choosing treatment modalities. The data presented in this study address the question of the psychometric adequacy of the measure in this segment of the subject population. Specifically, estimates of interrater reliability, internal consistency, and test-retest reliability are presented for a sample of 42 adult outpatients. In addition, the relationship between total protocol ratings and item sum scores is explored.  相似文献   
34.
Two individuals with severe mental retardation, employed by a janitorial supply company, were taught to use self-instruction in combination with multiple exemplar training to solve work-related problems. Use of the combined strategy resulted in generalization of the effects of independent variables, as well as generalization to nontrained problems. Use of the strategy is discussed in terms of promoting independent performance among supported employees.  相似文献   
35.
Ethical considerations in the use of computers in psychological testing and assessment are discussed. Particular attention is given to existing ethics and standards that provide guidance to users of computerized test interpretation and report-writing programs. Issues covering professional accountability and confidentiality are also discussed as they relate to computer-assisted assessment. Areas of appropriate use of computers in testing and assessment are suggested, including test scoring, the analysis of scores, and generating remedial recommendations. Findings are summarized and several guidelines are suggested for users of computers in testing and assessment.  相似文献   
36.
A Weiss 《Adolescence》1985,20(80):763-774
This study compared the symptomatology and diagnoses of adopted and nonadopted adolescents in a psychiatric hospital. Data were gathered from the hospital charts of adolescents who already had been discharged from the hospital. Contrary to expectations, adoptees were no more likely than nonadoptees to have received personality disorder diagnoses, nor were they more likely to be hospitalized as the result of antisocial behavior. However, in comparison with nonadopted adolescents, the adopted adolescents were younger upon admission to the hospital, significantly less often diagnosed psychotic, and significantly more often diagnosed adjustment reaction. It was suggested that adopted adolescents may be less likely than nonadopted adolescents to require severe or prolonged pathology in order to be admitted to a psychiatric hospital. It was also suggested that the antisocial symptomatology so frequently observed in adopted children in mental health settings does not account for the hospitalizations of those receiving inpatient treatment.  相似文献   
37.
Optimal timing and the Weber function   总被引:1,自引:0,他引:1  
  相似文献   
38.
Cultural differences in the predictors of depression   总被引:1,自引:0,他引:1  
This study examined a number of psychosocial factors thought likely to contribute to depression among ethnic Korean and Caucasian students. As hypothesized, Koreans (n = 61) were more depressed than Caucasians (n = 69). Stepwise multiple regression analysis revealed different models for predicting depression in the two groups. Value orientations, a neglected element in the prevailing stress paradigm, contributed substantially to variation in depression, especially among Koreans. Two measures of parental values and three coping strategies accounted for a striking 44% of the variance in Korean youths' depression. Perceived parental traditionalism, the strongest predictor, was associated with higher depression; and perceived parental modernism, with lower depression. For Caucasians, in contrast, only 13% of the variance in depression could be accounted for; and the two significant predictors were academic stress and respondents' own modern values (the latter associated with fewer symptoms). The findings of this study argue for greater attention to the importance of values in studying adaptation to stress.  相似文献   
39.
Mechanisms underlying satiation of feeding behavior of the mollusc Aplysia   总被引:1,自引:0,他引:1  
Animals filled almost to satiation by nonnutritive bulk do not satiate when they ingest a small amount of seaweed. This suggests that satiation is not triggered by chemostimulation of an anteriorly located "hot spot." Inflation of a balloon placed in the gut of the animal results in satiation as reflected in a number of different parameters of feeding behavior. The suppressive effect of a relatively brief inflation is rapidly and fully reversible, although repeated inflation and deflation appeared to produce slowly reversible or irreversible effects. The parameters of the changes in feeding during gut inflation are comparable to those of normal animals that are slowly fed individual pieces of food. The inflation volume needed to satiate the animal is a function of the rate of inflation--more rapid inflations requiring larger volumes. Cutting of the esophageal nerves results in a significant increase in the volume needed to satiate the animals, but nevertheless they eventually cease feeding and generally do not show a burst gut. The evidence indicates that the satiation that eventually occurs in nerve-sectioned animals, at least in part, is due to depression of feeding following very prolonged sensory stimulation. The data suggest that for a rapidly consumed meal, satiation results primarily due to distension-related gut signals conveyed by the esophageal nerves, whereas for very slowly consumed meals, the former factor interacts with a process associated with sensory stimulation, such as receptor adaptation. The current results indicate that balloon distension can serve as a reasonable stimulus in experiments in simplified preparations in which the nervous system can be studied.  相似文献   
40.
The present study was conducted to examine the hypothesis that compliant chronically ill patients, typically described as adjusted, reinforce more positive social environments using behavioral controls than noncompliant patients, typically described as maladjusted. Specifically, it is hypothesized that diet-compliant chronic hemodialysis patients emit significnatly more active involvement-in-treatment behaviors and more social behaviors than diet-noncompliant chronic hemodialysis patients. Subjects, who ranged in age from 30 to 77 years, were outpatients at a kidney center. Behavioral observations were conducted to assess the occurrence or frequency of (1) four involvement-in-treatment behaviors that are routinely taught to all patients and (2) two social behaviors, which were patient verbalizations and smiles. The results showed that compliant patients emitted significantly more involvement-in-treatment behaviors and smiles than noncompliant patients. Results support the proposed control framework that compliant, in contrast to non-compliant, chronically ill patients have recourse through positive behavioral controls when adjusting to the stresses of illness. It was proposed that through these controls, compliant patients reinforce positive environments rather than simply respond to life circumstances as given.  相似文献   
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