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101.
102.
The peak procedure was used in two experiments to study pigeons' ability to time multimodal events. In the first experiment, birds were trained to time a single event consisting of a 9-s tone or light followed by a 21-s fixed interval associated with a signal of light or tone (signal of the other modality). On occasional empty trials, different lengths of the first signal were followed by a long period of the second signal. Peak response times as a function of the duration of the first signal were linear and had a slope of close to one in all birds. This indicates that the birds were timing only the second signal. In a second experiment, two complex events were used in training. One consisted of a 9-s tone or light followed by a 21-s fixed interval associated with a light or tone. The other consisted of a 21-s tone or light followed by a 9-s fixed interval associated with a light or tone. Different durations of the first signal were again used on empty trials. Peak response times as a function of the duration of the first signal were again linear in all birds. The slope of the function was less than one but greater than zero for 3 birds. This indicates that these birds were partly timing the entire complex event of 30-s duration and partly timing only the second signal of the event. A model is proposed in which the bird takes as a criterion for timing a weighted average of different target criteria. Comparisons with the performance of rats are made.  相似文献   
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There is increased evidence that infants who receive poor quality social stimulation from their primary caregiver are at risk for later developmental difficulties. This paper describes a preventive intervention for mother-infant dyads exhibiting impaired patterns of social interaction. An impaired relationship with the primary caregiver has been found to be associated with social and emotional deficits in early childhood as well as with significant psychopathology in adulthood. The intervention consisted of group treatment of mothers and their infants. Each group session has 4 subsections which, together, were directed towards improving the mothers' ability to relate in a stimulating and nurturant manner to their children. Types of intervention included didactic instruction, modeling, and interpretation of the infant's behavior. Qualitative data suggested that the group intervention has positive effects on the mother-infant dyads.  相似文献   
106.
Estimates of the probability of various outcomes associated with treatment for kidney failure were made by chronic dialysis patients, dialysis patients awaiting transplant, successful transplant patients, and unsuccessful transplant patients back on dialysis. The latter two groups can be considered a natural experiment testing the impact of personal experience on population predictions. Consistent with the law of small numbers and the availability heuristic, successful transplant patients gave higher estimates of the population success rate for transplantation than unsuccessful transplant patients gave.  相似文献   
107.
The present study investigated (i) the conditions under which the proximal cause of an event affects judgments of a distal cause, (ii) the capacities persons need to be held responsible for their actions, and (iii) the relationship between judgments of causation, blame, and restitution. Subjects read about situations in which an initial act, in combination with a later behavior by a second person, produced harm. The age and mental state of the second person were varied. It was found that cause and blame assigned to the initial action was greater when the second person was a child or mentally disturbed, as compared to a sane adult. Causal and moral responsibility were related to the understanding, reasoning capacity, and ability to control behavior of the person judged. Finally, support was obtained for an entailment model of the relations between judgments of causation, blame, and restitution.  相似文献   
108.
Relative outcomes in social commerce with peers are potent determinants of cognitions and behavior in young children. Although there has been considerable attention given to the behavioral consequences of social comparisons following the receipt of rewards, there has been less concern with cognitive or affective consequences. Additionally, little is known about the accrued effects of multiple social comparison experiences that may be consistent or inconsistent with one another. In the present study, young children received a constant level of reward but the amount they saw a peer receive was varied. There were two sequences of reward distribution, and in a given sequence children received either the same number of rewards as the peer (=), more (+), or fewer (?). In a 3 × 3 factorial design all possible combinations occurred. A negative inequality in reward distribution, no matter where it fell in a sequence, made children sad and inclined children to distribute fewer rewards to peers. When a sequence contained an initial experience of positive inequality, children decreased subsequent levels of self-reward. Experiencing a comparison that revealed a negative inequality in reward distribution also disrupted children's accuracy in appraising the overall distribution of rewards: even when an initial negative inequality was completely offset by an equivalent experience of positive inequality, children inaccurately concluded that they had received fewer rewards than their peers.  相似文献   
109.
John M. McMaster 《Sex roles》1985,13(7-8):393-403
A structured questionnaire based on Rest's Defining Issues Test format was adopted to investigate the reasons used by 50 Black African males and 50 Black African females to explain their degree of acceptance of sex-role reversals. Both males and females showed little acceptance of sex-role reversals. The organization of the reasons they used to explain their degree of acceptance of sex-role reversals was most parsimoniously explained by Rest's complex stage model rather than the model suggested by Ullian, which is based on Piagetian stage criteria.  相似文献   
110.
Immediately after their first use of the dissecting room, 45 preclinical medical students rated their enthusiasm and reluctance at seven points along a time sequence encompassing their experience from the night before to the completion of their first dissection. A second group of 42 preclinical medical students carried out the same ratings in real time. A naive group of 24 psychology students were asked to imagine a first visit to the dissecting room and rate their imagined feelings in the same way. Gradients for reluctance for the two experimental groups rose to maxima at the point of entering the dissecting room. The reluctance gradient for the naive group and the enthusiasm gradients for all three groups, prior to this point, were zero. These are discussed as negative and positive motivational gradients that meet the predictions of approach/avoidance theory (Miller, 1959).  相似文献   
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