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881.
Alternate monocular and binocular exposure to complementary stimulation can yield opposite but coexisting aftereffects that are contingent on whether the test display is viewed with one eye or two eyes. The motion aftereffect was studied by adapting each eye separately to a contracting spiral and both eyes together to an expanding spiral. The stationary test spiral subsequently appeared to be expanding when viewed monocularly, but to be contracting when it was seen with both eyes open. With respect to the McCollough effect, after monocular exposure to red-vertical and green-horizontal gratings and binocular exposure to red-horizontal and green-vertical gratings, the appearance of the color of the test gratings when viewed with one eye was different from that when viewed with both eyes. Opposite, coexisting aftereffects induced by complementary stimulation can be interpreted as evidence that there are unique binocular aspects to visual function.  相似文献   
882.
It is well established that human observers respond more quickly to visual targets that appear in expected locations than they do to ones in unexpected locations. These variations in simple reaction time have been attributed to a covert alignment of an attentional mechanism to the expected target location. The present experiments investigated the influence of strength of signal and strength of subject’s positional expectancy on the magnitude of this attentional effect. In the first experiment, target luminance was varied over a range of three log units, and it was found that the effects of luminance were essentially additive with the effect of the positional expectancy (i.e., the attention effect). The second experiment found that the magnitude of visual attention interacts with the information value of the precue used to create the spatial expectancy, although, once again, luminance had additive effects. The resuls are interpreted as indicating that, rather than influencing early visual processing, the act of attending to a spatial location operates fairly late in the detection process.  相似文献   
883.
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   
884.
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   
885.
886.
A sample of delinquent and nondelinquent male adolescents was assessed with respect to locus of control and intellectual achievement responsibility. Data were also gathered concerning age, family size, birth order, socioeconomic status, race, and school grade. Results were subjected to a multivariate analysis and showed support for a multidimensional model of locus of control. There was no difference in expectancy of control for negative academic events between delinquents and nondelinquents. In general, birth order and delinquency were the two most important determinants of locus of control. Results are discussed in terms of previous literature on locus of control with particular consideration paid to expectations of control.  相似文献   
887.
The present study examined some previously reported relationships between drug use by adolescents and perceived attitudes and behaviors of their parents. An anonymous questionnaire was administered to the student body of an inner-city secondary school for difficult students. Relationships between parental use of drugs and adolescent use of the same drugs were moderate and roughly equivalent across drugs. However, parental use of marijuana was strongly related to the adolescent's use of other, harder drugs such as opiates, cocaine, amphetamines, and barbiturates. This finding is explained within the framework of Kandel's postulated stages of drug initiation. It points to a need for further study of parental influences, which may be increasingly problematic as more individuals who have grown up in our marijuana-accepting society become parents of adolescents.  相似文献   
888.
The authors recently proposed that adverse effects of material rewards on Wechsler subscale performance may be the result of a reward-produced developmental regression. The present study further explores that idea through an attempt to replicate earlier findings with adults and to extend the inquiry to children. Selected Wechsler subscales were administered to 32 subjects at each of three ages (5, 10, and 18 years) under either reward or nonreward conditions. Subscales were chosen to represent both algorithmic and heuristic types of tasks. Reward and nonreward groups (8 males and 8 females per group at each age) were matched initially on age and ability. For adults, consistent with earlier findings, reward had an adverse effect on performance on the heuristic subscales and tended to facilitate performance on the algorithmic subscales. However, rewards generally had no effect at the fourth-grade level and had a reverse effect at the nursery school level, i.e., rewards facilitated heuristic and hampered algorithmic performance. These findings appear to be more consistent with an explanation based on developmental regression than on any available alternative mechanism.  相似文献   
889.
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   
890.
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