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41.
Effortful and automatic memory task performances were examined in 36 schizophrenic patients and 18 normal control Ss. Tasks included free recall, recognition, and frequency estimation. Patients demonstrated impairment in recall, in recognition, in semantic encoding, and in frequency estimation. Deficits were observed across tasks despite differences in attentional demands. The results suggest a basic compromise of memory function, which is consistent with recent neuroimaging evidence of structural or physiological abnormalities in frontal and temporal lobe structures in schizophrenia.  相似文献   
42.
Thinking through uncertainty: nonconsequential reasoning and choice.   总被引:1,自引:0,他引:1  
When thinking under uncertainty, people often do not consider appropriately each of the relevant branches of a decision tree, as required by consequentialism. As a result they sometimes violate Savage's sure-thing principle. In the Prisoner's Dilemma game, for example, many subjects compete when they know that the opponent has competed and when they know that the opponent has cooperated, but cooperate when they do not know the opponent's response. Newcomb's Problem and Wason's selection task are also interpreted as manifestations of nonconsequential decision making and reasoning. The causes and implications of such behavior, and the notion of quasi-magical thinking, are discussed.  相似文献   
43.
The intent of this study is to apply a cross-level design to examine the influence of contextual factors upon individuals' performance. The results support the hypothesis that peer group characteristics predict individual performance beyond individual characteristics. The implications for using a cross-level approach to study the effects of contextual variables on individual-level phenomena are discussed.  相似文献   
44.
This article addresses the relationship between religious affiliation and a very specific form of firearms ownership, that is, handgun ownership. Literature is reviewed relative to explanations of gun ownership. A test of the hypothesized relationship between religious affiliation and handgun ownership demonstrated a statistically significant ( p < 0.03) association. Protestants were found to have a disproportionately high level of handgun ownership compared to other religious groups. Speculation for this finding is reviewed relative to other recent research on this topic.  相似文献   
45.
This article comments on a recent article by Heatherton, Herman, and Polivy (1991) in which they suggest that ego threats are a prerequisite to affectively induced disinhibition of food intake in restrained eaters and current dieters. In contrast, the present review suggests that mood induction procedures that involve no apparent threat (e.g., viewing a frightening film) can also prompt disinhibition in restrained eaters. Thus, any mood induction procedure that does not directly physically threaten the S may disinhibit restrained eaters. It is concluded that recommendations to focus future research on ego threats are premature and may serve to obscure the mechanisms by which changes in affective state influence food intake in dieters.  相似文献   
46.
This article describes the different reactions to emergency warning messages among residents living within a 3-km radius of a hazardous chemical complex and by people living at least 10 km from an industrial site in France, Greece, and the Netherlands. Belief in warning, primary and secondary appraisal, emotional response, and adherence to normal routine were assessed by conducting face-to-face interviews in which a four-phase scenario simulating a credible industrial accident was presented. The results showed that respondents who did not reside in the neighborhood of the hazardous site were, in general, more inclined to trust the warning messages than respondents who resided in the neighborhood were. With the exception of primary appraisal, the warning phases evoked very distinct reactions in the respondents from all three countries with regard to warning belief, secondary appraisal, emotional response, and adherence to normal routine.  相似文献   
47.
In the first experiment, 4 pigeons were each presented with a recurring sequence of four key colors followed by the delivery of grain (block clock). Once the rate of pecking had stabilized, three of the colors were replaced, during different series of sessions, by a darkening of the key. The rate of pecking was reduced within those segments of the interval between deliveries of food during which the key was dark; when the key was dark during the final portion of the interval, rates were reduced throughout the entire interval. In the second experiment, 3 new pigeons were exposed to a different sequence of colors, and the final stimulus was replaced in successive conditions by a novel color, a darkened key, and a restoration of the original color. The data indicated that darkening the key had a more severe, more extensive, and more persistent effect than did a mere change in color. These results suggest that it may be fruitful to conceptualize the autoshaping procedure as a special version of the block clock in which pecking is suppressed throughout the greater part of the interval by darkening the key. In the final condition, the same stimulus appeared in each of the last three portions of the interval. The rate of pecking was lower during the last two portions than when distinctive colors were presented, with the peak rate now appearing in the fifth of seven equal temporal components.  相似文献   
48.
This article describes further evidence for a new neural network theory of biological motion perception. The theory clarifies why parallel streams V1----V2, V1----MT, and V1----V2----MT exist for static form and motion form processing among the areas V1, V2, and MT of visual cortex. The theory suggests that the static form system (Static BCS) generates emergent boundary segmentations whose outputs are insensitive to direction-of-contrast and to direction-of-motion, whereas the motion form system (Motion BCS) generates emergent boundary segmentations whose outputs are insensitive to direction-of-contrast but sensitive to direction-of-motion. The theory is used to explain classical and recent data about short-range and long-range apparent motion percepts that have not yet been explained by alternative models. These data include beta motion, split motion, gamma motion and reverse-contrast gamma motion, delta motion, and visual inertia. Also included are the transition from group motion to element motion in response to a Ternus display as the interstimulus interval (ISI) decreases; group motion in response to a reverse-contrast Ternus display even at short ISIs; speed-up of motion velocity as interflash distance increases or flash duration decreases; dependence of the transition from element motion to group motion on stimulus duration and size, various classical dependencies between flash duration, spatial separation, ISI, and motion threshold known as Korte's laws; dependence of motion strength on stimulus orientation and spatial frequency; short-range and long-range form-color interactions; and binocular interactions of flashes to different eyes.  相似文献   
49.
The influence of a videotape, shown in a hospital admitting room, on patients' state anxiety and concerns about hospitalization was assessed in a preliminary study. For both state anxiety and specific concerns regarding hospitalization the pretest scores on each variable accounted for the preponderance of the variance in the posttest scores. In both instances, the intervention and the interaction of the intervention with the pretest scores accounted for less than 1% of variance in the outcome. While finding small effects to be significant for such a small sample (N = 93) is unlikely, the sample size was adequate to detect medium to large effects. More important was the fact that 73.33% of the videotape intervention group indicated that they did not watch the video, which leads us to the conclusion that this intervention as tested is not worthwhile.  相似文献   
50.
This study was designed to investigate the comparability of the original MMPI (1950) and the MMPI-2 (1989) with a psychiatric patient population. 34 male and 3 female patients, shortly after admission to one of two acute psychiatry units, completed the old and revised versions of the MMPI. Paired t tests indicated but scant differences for raw scores, while many more differences were found among T scores for validity, clinical, and supplemental scales. Analyses, however, showed all scales on the two forms to be highly correlated. Analysis of the high-point and two-point codes across the two administrations also showed relative stability, although the proportion of Scales 2 (Depression) and 8 (Schizophrenia) decreased, while those for Scales 6 (Paranoia) and 7 (Psychasthenia) increased markedly in the MMPI-2 protocols. Examination of each version's discriminability among mood- and thought-disordered subsamples suggested that the MMPI provides slightly better delineation between diagnostic classes. Discriminant function analyses showed that there were essentially no differences between the two forms in the accurate classification of clinical and nonclinical groups. The findings reported here provide support for the MMPI-2; despite modification, the newer form retains the advantages of the original MMPI. Differences found here may be unique to psychiatric patients and their patterns of MMPI/MMPI-2 equivalence and may not generalize to other special populations.  相似文献   
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