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951.
Relative effectiveness of three stimulus variables for locating a moving sound source 总被引:1,自引:0,他引:1
A study is reported in which it is shown that observers can use at least three types of acoustic variables that indicate reliably when a moving sound source is passing: interaural temporal differences, the Doppler effect, and amplitude change. Each of these variables was presented in isolation and each was successful in indicating when a (stimulated) moving sound source passed an observer. These three variables were put into competition (with each indicating that closest passage occurred at a different time) in an effort to determine their relative importance. It was found that amplitude change dominated interaural temporal differences which, in turn, dominated the Doppler effect stimulus variable. The results are discussed in terms of two interpretations. First, it is possible that subjects based their judgements on the potential discriminability of each stimulus variable. However, because the stimuli used involved easily discriminable changes, subjects may instead have based their judgements on the independence of a stimulus variable from different environmental situation conditions. The dominance ordering obtained supports the second interpretation. 相似文献
952.
G. V. Caprara T. Gargaro C. Pastorelli M. Prezza P. Renzi A. Zelli 《Personality and individual differences》1987,8(6)
After inducing hostility toward a confederate by threatening subjects' self-esteem, subjects were then given the opportunity either to deliver shocks (Experiment 1) or to withhold rewards (Experiment 2) from their confederate. Physiological measures were taken prior to the hostility induction, shortly after the induction and, finally, after the opportunity to aggress. Measures of individual differences relating to aggressive behavior were also considered. While the experimental manipulation was the best predictor in the ‘withholding rewards’ condition, measures of dissipation-rumination tendencies and emotional vulnerability were the best predictors in the ‘shock administration’ condition. In both conditions, systolic blood pressure seemed to reflect differences in arousal as a function of the hostility induction procedure, while subjects in the withhold rewards procedure also showed a decrease in systolic pressure after having an opportunity to aggress toward the confederate. It was concluded that not only is the withholding of rewards a more ethically acceptable procedure than shock administration, but it is also more likely to reflect experimental rather than individual difference affects. 相似文献
953.
J C Bartlett M A Gernsbacher R E Till 《Journal of experimental psychology. Learning, memory, and cognition》1987,13(1):27-35
In a study of recognition memory for pictures, we observed an asymmetry in classifying test items as "same" versus "different" in left-right orientation: Identical copies of previously viewed items were classified more accurately than left-right reversals of those items. Response bias could not explain this asymmetry, and, moreover, correct "same" and "different" classifications were independently manipulable: Whereas repetition of input pictures (one vs. two presentations) affected primarily correct "same" classifications, retention interval (3 hr vs. 1 week) affected primarily correct "different" classifications. In addition, repetition but not retention interval affected judgments that previously seen pictures (both identical and reversed) were "old". These and additional findings supported a dual-process hypothesis that links "same" classifications to high familiarity, and "different" classifications to conscious sampling of images of previously viewed pictures. 相似文献
954.
Stephen M. Williams 《Current Psychology》1987,6(2):148-154
Previous experimental investigation of the effects of repeating an unfamiliar stimulus suggests that mere exposure breeds
attraction (e.g., Zajonc, 1968). On the other hand, correlational work with naturally occurring stimuli such as names, music,
or landscapes suggests that there is also an overexposure effect: the preference function does rise with familiarity at first
but then reaches a turning point and diminishes. The study (N=72) demonstrates this inverted-U relationship in an experimental setting. The stimuli were synthetic nonsense speech, permitting
exact control of exposure durations and interstimulus intervals. The critical factors for demonstrating the effect are probably
(1) the inclusion of a large number of repetitions, and (2) blocked repetition of each stimulus in a homogeneous sequence
not interspersed with other more or less frequent stimuli. 相似文献
955.
Sixteen student volunteers were administered a placebo and 50 mg. of chlorpromazine in tablet form, on separate occasions,
two hours before testing. The three tests measured dichotic listening performance, lateral eye movements while answering questions
about spatial location and verbal meaning, and lateralized facial expression while relating pleasant and unpleasant life incidents.
Results showed that chlorpromazine increased the number of trials showing an ear advantage in dichotic listening. Chlorpromazine
reduced lateral and increased vertical eye movements in response to the questions about spatial location and verbal meaning.
Under the placebo both negative and positive emotions were expressed more in the left face. Although chlorpromazine did not
affect this lateralization of negative emotions, the expression of positive emotions occurred equally often on the two sides
of the face under chlorpromazine. Results may be related to an effect of chlorpromazine on the asymmetrical dopamine pathways
of the brain. It is suggested that the findings may be related to a left hemisphere deficit in schizophrenia. 相似文献
956.
957.
Orlando J. Andy M.D. 《Integrative psychological & behavioral science》1987,22(4):132-144
Chronic pain consisting of anesthesia dolorosa secondary to bilateral interruption of the trigeminal nerves is presented as a brain stem reticular denervation syndrome. Electrothalamograms revealed fast frequency discharges in the mesothalamic prerubral and centermedian reticular formation. Mesothalamic electrical stimulation attenuated the discharges. Pain and other symptoms presumably of brainstem origin also were attenuated or abolished by therapeutic electrical stimulation twice daily. It is postulated that brain stem-represented behavioral generators are implicated by the reticular discharges in order to produce the complex symptomatology. Consequently the symptom complex is collectively identified as a brainstem “mini-discharge” syndrome. A theoretical discussion is presented to defend the thesis that reticular denervation-induced low threshold discharge system accounts for the episodic states of pain, dyskinesia, mood, and memory disturbances. 相似文献
958.
The present study examined observers’ ability to discriminate canonical and dynamically anomalous collisions that were presented in either frictionless or frictional systems. Whereas previous research has provided qualitative demonstrations that dynamic information can be extracted from visual events, the current study provides a parametric assessment of observers’ sensitivity to dynamic invariants. Our findings indicate that observers are competent when viewing both familiar, terrestrial (frictional) systems and unfamiliar but computationally simpler, 0-G (frictionless) systems. Thus, our sensitivity to these dynamic invariants in visual events is robust in natural systems whose dynamic properties differ from those of the environment in which we evolved and developed. 相似文献
959.
A questionnaire monitoring occupational aspiration, ethnic identification, adolescent experience, and self-esteem was administered to a large sample of Indian and Anglo-Saxon British male and female adolescents attending school in the West Midlands. The relationship between these variables and differences between the four groups were consistent with predictions derived from the social identity approach to intergroup relations and group behaviour (Tajfel & Turner, 1979). Indian males were found to possess a social mobility belief structure that mediates high occupational aspirations and keeness to marry out of their ethnic group. In contrast, Indian females were found to possess a social change belief structure associated with acceptance of the status quo and lower aspirations. Males and Anglo-Saxons reported higher self-esteem than females or Indians. The adolescent experience findings were less clear, but were consistent with the general interpretation of the data that the differences in intersex relations and gender-related experiences are contingent on ethnicity. 相似文献
960.
Dermot M. Bowler 《Behavior research methods》1987,19(4):377-379
A suite of programs is described that enables an Apple II+ microcomputer to control slide projectors and shutters as a two-field projection tachistoscope. This system is portable and allows more precise exposure timings and more complex visual stimuli to be used than are possible with earlier systems. 相似文献