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61.
The number of active sweat glands (PSI), heart rate, systolic (SBP) and diastolic blood pressure (DBP) were assessed every 2 minutes in 109 male blood donors. Three measurements were taken at the beginning (adaptation phase), three later but before blood donation (baseline), one during the venous puncture (phase 3), three thereafter but still during donation (phase 4), and four after removal of the cannula (phase 5). Analysis of variance yielded significant differences between phases; PSI and SBP behaved similarly, decreasing from adaptation to baseline, rising during puncture, and decreasing again thereafter. Mean within-subject correlations between variables were significantly above 0. Between-subjects correlations were significantly negative for PSI and DBP. This is best explained by the influence of age on both variables. Correlations of PSI values as determined by three raters had a mean of 0.90. The study shows that the PSI is a very sensitive indicator of stress that is easily accessible also in field studies.  相似文献   
62.
An investigation was made into the extent and time course of anticipatory coarticulation in the speech of two normal and two anterior aphasic, German-speaking subjects. Both labial and velar coarticulation gestures were investigated. Subjects produced sentences containing target words contrasting in postconsonantal vowel rounding (e.g., [geli:ge]/[gely:gel]) and in nasality (e.g., [ti:de]/[ti:ne]). Speech kinematics were monitored by means of electromagnetic articulography. The data revealed that for correct productions, aphasic speakers' coarticulatory patterns were more highly variable than those of control subjects. These differences, however, were found chiefly for spatial displacement characteristics, while the temporal aspects of articulator movement necessary for anticipatory coarticulation appeared largely intact. Articulator mistiming did not appear to explain a small corpus of stop/nasal substitution errors produced by one of the aphasic speakers.  相似文献   
63.
Abstract— Three experiments reported here provide empirical support for the hypothesis derived from terror management theory that unconscious concerns about death motivate allegiance to cultural beliefs, Study 1, contrasted exposure to a subliminal death-related stimulus, a standard mortality-salience treatment, and a neutral subliminal stimulus, and found that both the subliminal and the standard reminder of mortality led to more favorable evaluations of people who praised subjects' cultural worldview and more unfavorable evaluations of those who challenged it Study 2, replicated this finding by comparing the effects of exposure to subliminal death stimuli and subliminal pain stimuli. Study 3, contrasted subliminal death stimuli, supraliminal death stimuli, and subliminal pain stimuli and found that only subliminal death stimuli produced these effects.  相似文献   
64.
Final-year nursing students (N= 96) described their anxieties about biohazards, not only in relation to the occupational context of a hospital ward, but also in relation to their general life context. These contexts were reported to vary in the extent to which they permitted control over exposure to the two particular biohazards chosen for study: human immunodeficiency virus (HIV) and hepatitis B virus (HBV). The data showed that nurses' anxiety about contracting HIV infection varied significantly across the two contexts, while anxiety about contracting HBV infection did not. In the general life context, anxiety about HIV was greater than anxiety about HBV for all subjects. This difference was significantly greater for those with incorrect knowledge about objective HIV seroconversion rates than for those with correct knowledge.  相似文献   
65.
66.
Behavior analytic evaluation instruments should benefit teacher education programs in assessing: (a) teacher and student interactions in practice teaching settings, and (b) the immediate and long range effects of the teacher training received. Though empirical substantiation remains scarce, such instruments may be designed to foster teacher trainee sensitivity to, and better control of, complex stimulus and response mechanisms which either impede or facilitate learning. This study analyzed one technologically driven Behavior Analysis Strategy and Taxonomy (BEST) and related Temporal Analysis System (TAS) (Hawkins, Sharpe, & Ray, 1994) currently used within one preservice teacher education program. A multiple probe design with experimental and control groups demonstrated the instruments' effects when used as an instructional feedback tool with teachers in training. Findings supported the instruments' use in terms of teacher and student behavior changes demonstrated for the experimental group as compared to a control group not exposed to the instrument. Implications of this technology when applied to teacher education are last described.  相似文献   
67.
This paper addresses a problem in reporting scientific research. The problem is how to distinguish between justifiable and unjustifiable data selection. Robert Millikan is notorious for an infamous remark that he used all his data when in fact he had used a selection. On this basis he has been accused of fraud. There is a tension here — historians and his defenders see his selection as understandable and legitimate, while current statements about the Responsible Conduct of Research imply his selection was illegitimate. This paper discusses two main issues that arise in assessing his conduct, whether he was intentionally misleading and whether he actually did mislead the scientific community about some facts of nature. It is argued that he was not intentionally misleading, and that it is unlikely that he misled the scientific community.  相似文献   
68.
We report on the use of our Sniffy program to teach operant conditioning to 900 introductory psychology students. The simulation is designed primarily to teach the principles of shaping and partial reinforcement in an operant chamber. Advanced features are provided for exploring modeling issues and the learning parameters of the model. Students observe the rat’s pretraining behaviors, shape barpressing, and explore the effects of partial reinforcement schedules on a cumulative record. Any of 30 actions can be trained to occur in specific locations in the Skinner box. This paper summarizes details about the software, interface, and instructional objectives.  相似文献   
69.
Musically trained and untrained subjects (N=30) were asked to synchronize their finger tapping with stimuli in auditory patterns. Each pattern comprised six successive tonal stimuli of the same duration, the first of which was accented by a different frequency. The duration of interstimulus onset intervals (ISIs) gradually increased or decreased in constant steps toward the end of the patterns. Four values of such steps were used in different trials: 20, 30, 45, and 60 msec. Various time-control mechanisms are hypothesized as being simultaneously responsible for subjects’ incorrect reproduction of the internal temporal ratios of the stimulus patterns. The mechanism of assimilation (of a central tendency) led subjects to enforce a regular (isochronous) structure on the patterns. The influence of other time-control mechanisms (distinction, subjective expression of an accent, sequential transfer) was expressed mainly in differences between intertap onset intervals (ITIs) and the corresponding ISIs at the beginning of the patterns. The duration of the first two ITIs was in the majority of the trials in an inverse ratio to the ratio of the respective ISIs. The distortions resulting from the timing mechanisms concerned were more pronounced in the performance of nonmusicians than in that of musicians.  相似文献   
70.
Estimates of temporal proximity (sometimes called time-to-collision) from random-dot flow patterns are shown to be based upon retinal speed, rather than upon changes in dot density. Neither the spatial nor the temporal gradient of motion is essential to the task, but estimates can be made from either alone. Performance is unaffected by the addition of rotational motion, suggesting that observers axe capable of extracting the radial component of motion, which contains all the relevant information, from complex stimuli.  相似文献   
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