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21.
An overview is presented of a pilot psychoendocrine study of PTSD inpatients in comparison with several subgroups of schizophrenic and affective disorder patients. Using a hormonal profile including Cortisol, norepinephrine, epinephrine, testosterone, and thyroxine, it was found that the mean values for the PTSD group were at or near the extreme end of the range for every hormone measured, i.e., relatively low for Cortisol and high for the remaining hormones. The possible clinical meaning of these findings is considered in the light of prior psychoendocrine research on chronic stress. The hormonal alterations in PTSD appear to be persistent and suggest the possibility of being linked largely to traits or character structure, perhaps particularly to cognitive variables related to defense and coping mechanisms, as reviewed in detail for each hormonal system. There appears to be a potential for a fruitful union between the traumatic stress and psychoendocrine fields and some future strategies for developing and strengthening such a union are suggested.  相似文献   
22.
The essay examines the argument advanced by E.D. Hirsch, Jr., for instituting ‘cultural literacy’ as a fundamental priority of schools. A number of confusions and equivocations in Hirsch's reasoning are identified, and the propensity of his project to indoctrinate is exposed. Among the features of Hirsch's argument shown to be troubling are his shifting construal of ‘language’, his inconsistency about the requirements of cultural literacy, and his uncritical relation to traditional images of the American past and present. The upshot is to raise the question why Hirsch's project has elicited wide support and praise.  相似文献   
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ABSTRACT It has been hypothesized that individuals who are high on the attribute of self-criticism are particularly vulnerable to failure stress. To test this hypothesis, we examined the relationship between self-criticism and changes in plasma homovanillic acid (HVA; the metabolite of dopamine) and emotion during exposure to an induced-failure task. Participants consisted of 21 women. Plasma HVA and emotion were assessed at three time points: baseline (T1), during stress exposure (T2), and 40 minutes after cessation of the stressor (T3). We found that self-criticism was significantly and positively related to changes in plasma HVA during stress exposure. In addition, the personality attribute was significantly and positively related to subjective ratings of stress and changes in scores on the Confusion-Bewilderment scale of the Profile of Mood States during the task. To our knowledge, this is the first study to report that self-criticism is related to stress-induced changes in biochemistry.  相似文献   
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How can we explain that an assertion on something perceived can be understood in the same manner by somebody who cannot perceive that scene? This problem bases the interest in computational linguistics in how listener modeling could possibly be harmonized with reference semantics. Mental images substituting real perception appear as a way out. The architecture of the listener model has to be adapted to the creation and use of such pictorial data structures. Furthermore, the relation between the latter and a verbal (i. e., propositional) representation must be understood. The resulting architecture of a listener model with reference semantics can be employed to solve communicational problems from three general classes in a better way, as is demonstrated by an example implementation.  相似文献   
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The present studies assessed the degree of stimulus control exerted by S+ and S? without confoundings of stimulus novelty and stimulus ambiguity. In Experiment 1, rats were trained on two intercurrent simultaneous discrimination problems with nine times more training given on one than the other. Then the animals were given transfer tests with re-paired stimuli. The results showed that S? exerts greater stimulus control than S+ in a two-choice simultaneous discrimination. Experiment 2 provided a test of the possibility that the relative degree of control by S? varies with different amounts of training. Three groups were trained on two intercurrent simultaneous discrimination problems; each group was given 7, 11, or 15 times more training on one problem than the other. Then transfer tests were given with re-paired stimuli. Again the results showed that S? exerts greater stimulus control than S+ in a two-choice simultaneous discrimination.  相似文献   
28.
Three experiments address the question of whether end-effects (the advantage for the first and last letters in multi-letter arrays) are due to sensory or cognitive factors. The basic strategy used was to compare letters with symbol stimuli that do not lend themselves to top-down processing. Serial position functions using central fixation were obtained in the first experiment for letters, digits, and symbols. End-effects were present with both letters and digits, indicating that processes limited to word recognition cannot be responsible for end-effects. Five-symbol arrays, however, yielded U-shaped reaction time functions, with poorest performance at the initial and terminal positions. The effects of array size and retinal placement were investigated with letters and symbols in a second experiment. Multi-letter and symbol arrays differed primarily in that letters showed end-effects that were independent of retinal placement, whereas symbols did not. The conclusion that multi-letter and symbol arrays are not processed in the same way was tested in a third experiment. Using a paradigm that eliminated processing order as a variable, the experiment obtained identical effects of ordinal position within an array for letters, digits, and symbols. It is concluded that sensory factors cannot provide a viable account of letter end-effects and that letter and nonletter comparisons can improve our understanding of the sensory and cognitive factors involved in letter perception.  相似文献   
29.
Observers searched for a single precued word or its nonword anagram under conditions of rapid serial visual presentation (RSVP). A word advantage was found over a wide range of presentation rates (32-160 msec/frame), under yes-no as well as forced choice conditions, and with both one or two input “channels.” These results suggest that word superiority in word detection occurs at a perceptual locus.  相似文献   
30.
Rhesus monkeys were raised with dogs or inanimate surrogates in outdoor cages which provided them with complex, highly varied visual surroundings. Visual responsiveness to a variety of colored transparencies was investigated in three experiments, completed when the monkeys were between 18 and 30 mo old. Results indicated that the frequency and duration of looking at slides was significantly higher for dog-raised than for inanimate-surrogate-raised monkeys and that dog-raised monkeys were much more responsive to the novelty, complexity, ansal were obtained during the final experiment. Heart rate, vocalization, and changes in plasma cortisol were higher for monkeys raised with dogs. The frequency of most self-directed behaviors, however, was higher for monkeys raised with inanimate surrogates. Differences between rearing groups can only be the result of contrasts in attributes of the substitute mothers.  相似文献   
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