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991.
Thirty-two mother-father-infant triads participated in a study to examine whether parents' responsiveness to their own infant's distress was affected by the infant's birth order and gender. After separating from their 10- to 11-month-old baby, one parent from each family (16 mothers and 16 fathers) was selected to hear cries that were attributed to the child. Consistent with previous findings regarding physiological reactions to crying and observations of caretaking behavior, first-time parents gave quicker and more frequent attention to their infants than did multiporous parents. Speedy intervention was related to the amount of caretaking responsibilities that parents reported they assumed and to the age at which parents believed that their infant first recognized them. The results demonstrate the importance of caretaking for promoting parental sensitivity to infant signals.  相似文献   
992.
Considering the findings that schizophrenics have been found to show relatively slow reaction times (RTs), and often do not benefit from ordinarily helpful information (e.g. a warning signal), the present study investigated the relationship between these variables and psychoticism (P). One hundred and three male Ss were administered a questionnaire which provides a measure of P. In addition, all Ss were tested on an RT task under unsignalled (i.e. no warning signal) and signalled conditions. The results showed that the expected improvement in reaction speed with a warning signal was of a lesser magnitude for those high on P. Furthermore, the difference was due to the faster RTs for high P scorers in the unsignalled condition. The data suggest that high P scorers are like schizophrenics in that they show less benefit from a warning signal, but are dissimilar in terms of reaction speed in an unsignalled task.  相似文献   
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996.
Cornell University Medical College, Westchester Division, The New York Hospital, White Plains, New York It is well established that there is a complex timekeeping mechanism in the human brain. This mechanism is associated with a variety of physiological and psychological rhythms having a period of about a day, and thus referred to as circadian rhythms. The circadian system has recently been modeled in terms of two underlying oscillators, one much more resistant to changes in routine than the other. These oscillators are considered to be endogenous, that is, internal to the organism, and not reliant for their existence upon changes in the person’s environment or general behavior. They thus continue to run even when the sleep/wake cycle is suspended, as in sustained operations. Thus, by their very nature, sustained operations require the individual to override the inputs that are coming from his or her circadian system (especially the indication that sleep is required). The aim of this paper is to provide a background to the area of circadian rhythms research, including a section on the methodology, so that the impact of the circadian system on sustained operations can be better understood.  相似文献   
997.
Expectancy theory concepts were used to predict (a) the attractiveness of, (b) the amount of effort directed toward entering, and (c) the eventual choice of a job in relatively big and small work organizations. It was found, among a group of graduating seniors from a technical college, that antecedent perceptions regarding organizational size (expectancy, valence, instrumentality) were significantly related to the relative attractiveness of different-sized organizations and the number of job interviews taken with relatively big and small companies. In addition, economically tied extrinsic outcomes were seen as more readily attainable in big organizations, whereas certain intrinsic outcomes were perceived to be more easily obtained in small organizations.  相似文献   
998.
Lane has argued that kantowitz and Knight incorrectly predicted an interaction between primary and secondary task difficulty for the variable-allocation model of attention. It is shown that such an interaction is indeed obtained if task-performance difficulty is defined in terms of capacity and only reasonable transformations of data are permitted. This interaction holds for any set of monotonic resource operating characteristics.  相似文献   
999.
The study examined the effects of providing six levels of research information to 270 classroom subjects on the data obtained from three different cognitive tasks. The effects of the three tasks on the subjects' academic self-concepts were also investigated. No significant differences were found among the six levels of information for each of the three tasks. On the logical task a significant linear relationship was found supporting previous research which indicates that the more information that is given to research subjects, the more negative the results. There were no significant differences on self-concept scores across the three tasks used. Overall, the implementation of ethical principles had little effect on data collected in classroom settings, indicating support for implementation. This data did indicate, however, that providing more information than required under the ethical principles can result in data bias on a specific task.  相似文献   
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This research compared the retention of nouns, adjectives and verbs of sentences. A model of the structure underlying the retention of sentences and in which deep structure constituent propositions are hierarchically related, was used to make predictions concerning the retention of these word classes. The model was not supported by the data and it was determined that latencies to recognize the words of a previously presented sentence were the same for all classes of words. This result indicated that for recognition (but not necessarily for other memory tasks), each word of a sentence is seperately or equally accessible (as long as inter-word imagery is the same). However, a further experiment showed that, although word class is not a variable, the image-arousing capacity of a word is. Latencies and error rates were much lower for high-imagery words than for low-imagery ones. The findings on error rates in recognizing words were interesting and pointed to a different model where the meaning representations and syntatic functions of words have an active role in sentence retention.  相似文献   
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