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901.
An analysis of some sensitizing agents in the pathogenesis of stress-induced gastric erosive disease
B. H. Natelson M. Ferrara-Ryan D. Creighton J. Yavorsky G. Curtis W. N. Tapp 《Integrative psychological & behavioral science》1984,19(4):195-199
Prior surgical implantation of a venous catheter sensitized rats to coldimmobilization stress. Three of six catheterized females succumbed during the stress. The remaining rats fell into two groups in terms of their core temperature at the end of the stress period: Male uncatheterized rats had higher temperatures than rats in the other three groups. No relation was found between catheter patency and magnitude of hypothermia. Degree of gastric disease paralleled the core temperature findings in that the male uncatheterized rats had significantly fewer gastric erosions than the rats in the other three groups. Additionally, a robust effect of gender was found with uncatheterized females showing more hypothermia and more gastric disease than uncatheterized males. A subsequent experiment was conducted to evaluate whether anesthesia or wearing the protective spring was responsible in part for the sensitization seen. Here, the gender difference was less although females consistently averaged lower core temperatures after stress than did males. Despite similar core temperatures after stress, females that were prepared with the protective spring apparatus developed more gastric disease than female controls or similarly treated males. Thus, the additional sensitization exhibited by females in the first experiment may relate to the fact that both catheterization and the taping procedure were sensitizers while only catheterization was a sensitizer for males. 相似文献
902.
S. Stefan Soltysik Thomas Nicholas W. Jeffrey Wilson 《Integrative psychological & behavioral science》1984,19(4):169-181
Respiratory rate, respiration amplitude, and vocal responses were recorded in cats of different ages during classic conditioning. Vocal responses to the conditional stimulus (CS) appeared first in 8-week-old kittens, and became prominent at older ages. An increase in respiration rate occurred after the onset of the CS in cats of all ages. Similarly, the decrease of respiration amplitude was observed at all ages, but only in 8-week-old and older subjects did this response resemble an adult pattern. In 4-week-old kittens the response was characterized by an early and brief peak, suggesting an alpha conditional response (CR). Clear and significant discrimination between a warning and a safety signal was present in both respiratory and vocal responses after the age of 8 weeks. 相似文献
903.
Jacquelyn Cranney Howard S. Hoffman Michelle E. Cohen 《Attention, perception & psychophysics》1984,35(2):165-172
When a relatively weak signal, such as a mild tone, precedes an intense reflex-eliciting stimulus by an appropriate interval (about 100 msec), the amplitude of the elicited reaction is often reduced. It was found that in student volunteers a brief gap in a steady pure tone that occurred 150 msec prior to a mild tap to the glabella (the flat region between the eyebrows) could inhibit the eyeblink elicited by the tap. It was also found that a shift in tonal frequency across a gap in a tone was more inhibitory than a gap with no frequency shift, but it was no more inhibitory than the onset of the short second tone alone. The final study determined the minimum amount of frequency shift required to produce an additional inhibitory effect above that of a gap alone. The findings are discussed in terms of various aspects of sensory processing. 相似文献
904.
Rebecca Logsdon Larry Hochhaus Harold L. Williams O.H. Rundell Dale Maxwell 《Acta psychologica》1984,55(2):179-193
An experiment which employed each of 18 subjects in four days of testing was used to examine acute secobarbital dose treatment effects on choice reaction time in a Cooper and Shepard (1973) character recognition task. Manipulations of visual stimulus degradation, character difficulty, 180 degree rotation, and mirror-image reversal were included in order to evaluate the hypothesis that the drug affects performance by disrupting early stimulus input processing. The results indicate significant increases in the effect of secobarbital on reaction time and errors under conditions of visual stimulus degradation. The effects of the drug, however, were not changed by 180 degree rotation of the target character or by the other task variables. The results were interpreted to indicate that secobarbital impairs performance primarily by placing selective stress on hypothetical early encoding activities and that later processing operations (associated with use of an internal representation of the target character) are not affected by the drug. Strengths and weaknesses of the two-stage model of visual stimulus processing are discussed and implications of the model for future drug research are indicated. 相似文献
905.
The relationship between the availability of visual information and attention demands during the production of a discrete motor act was examined. Subjects were required to move a linear slide a distance of 15 cm in both 150 and 600 msec conditions under three light manipulations, viz., light always on; light always terminated as movement began; or, subject was unsure as to whether light would stay on or terminate. A simple key press by the index finger of the opposite hand to a tone was used as a secondary task and a measure of attention demands. The light manipulation influenced attention demands on the rapid 150 msec movement such that more attention was demanded when the subject knew the light would terminate. No such attentional strategy differences were found with the slow 600 msec movement. These findings suggest that task constraints in the form of kinematic criteria, together with the perceived availability of visual information, contribute to determining attentional strategy in movement production. 相似文献
906.
W S Poland 《Journal of the American Psychoanalytic Association》1984,32(2):283-299
It is by the application of the principle of neutrality, born of his respect for the essential otherness of the patient, that the analyst focuses the dyadic analytic work in the service of the patient's growing self-analytic capacity. Thus, the general principle of neutrality is distinguished from the technical tactic of abstinence, the latter being a specific function utilized to facilitate and foster analytic regression. Neutrality can be defined as it applies to the major subfunctions of the analyst's work ego. Perception of the patient's intrapsychic processes (both empathically and cognitively) requires a neutrality of appearance on the analyst's part in order to minimize the distortion of the unfolding transference neurosis. Integration and understanding of the patient's communications require mastery and neutralization of the analyst's own internal processes in order to minimize countertransferential distortions. Appropriate interpretive intervention requires neutrality of action, i.e., mastery of impulses related to power, neutralizing them into the service of the analytic work; tact is defined as a specific psychoanalytic function in this regard. Collaborative ignorance is examined as a specific instance of false neutrality. In this an analytic guise serves to mask a countertransferential conflict. Neutrality serves as an overriding technical principle, not an imperative for perfectionism . Factors intrinsic to the analytic process also influence the application of this principle. 相似文献
907.
908.
909.
Traditional strategies for determining whether a reinforcer schedule enhances the occurrence of an activity are reviewed and critically evaluated. A basic assumption underlying these strategies is that it is possible to isolate the effect of reinforcer intermittency on schedule induction. It is concluded that this is not, in fact, possible. An alternative approach is proposed that emphasizes the inductive effects of the reinforcer schedule as a unit and the effects of particular aspects of the reinforcer schedule (e.g., interreinforcer interval, repetition of the reinforcer, reinforcer magnitude). 相似文献
910.