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41.
The influences of sex, age, and conversational, partner (mother vs. stranger) on eye contact during verbalizations were examined in a longitudinal study of 33 children at 2 and 4 years of age. A free-play sample was obtained of each child interacting with mother and with a male or female experimenter. The amount of eye contact in conjunction with verbalization was analyzed. Significant main effects were found for sex (females engaged in a higher percent of eye contact than males) and conversational partner (more eye contact while speaking exhibited to experimenter than to mother). There was an interaction between age and conversational partner, in that mother received more and experimenter relatively less percent of eye contact during verbalizations as children got older. Notably, there was no main effect for age. These results revealed sex differences at an age (2–2 1/2 years) and in a context (free-play setting) not previously studied, demonstrating the robustness of the effect. Further, age findings seem indicative of unique developmental trends for eye contact during verbalizations for the ages between 2 and 4 years.Mount Saint Vicent University  相似文献   
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43.
The possibility that rats can navigate in the Morris water maze by reducing the difference between the memorized platform scene and the current sensory input was tested in nine blind rats. A computerized videosystem monitored the rats' movements in the pool and converted the rat-target distance into tones the frequency of which increased in 64 equal steps from 120 Hz at 128 cm to 7680 Hz at 0 cm. During 15 days of training to find a fixed platform position from different starting points (12 trials per day) average escape latencies decreased from 39.0 to 25.4 s. The performance significantly deteriorated when the acoustic distance signalization was omitted and/or when the target position was changed form trial to trial. It is concluded that blind rats solved the task by simultaneously employing search strategy based on position responses, mapping using acoustic background beacons, and distance reduction navigation. It is argued that the various strategies are additive and that their relative significance depends of the conditions of the experiment.  相似文献   
44.
Previous theories of intrinsic motivation have traditionally ignored the experiential or subjective aspects of engagement in intrinsically and extrinsically motivated tasks. Part of the reason for the lack of research in this area was our ignorance of which emotions to study. Data are presented here from two studies designed to produce the first systematic evidence of changes in basic emotional states during task engagement. Our findings suggest that intrinsic and extrinsic tasks can be differentiated according to the emotional changes subjects retrospectively report about their engagement with these tasks, and point the way to future research incorporating emotion as an important variable to consider.The first author was supported in part by a Minority Fellowship administered by the American Psychological Association under a Clinical Training Grant from the National Institute of Mental Health (5 T01 MH13833), and by a Regents Fellowship from the University of California, Berkeley.  相似文献   
45.
Action sentences     
David Widerker 《Erkenntnis》1988,28(2):269-291
I would like to thank Eddy Zemach, Jonathan Stavi, Julius Moravcsik and Dov Gabbay for some very good discussions on the logical form of action sentences. Also, I am indebted to an anonymous referee of Erkenntnis for some very helpful comments on an earlier draft of this paper.  相似文献   
46.
In a study of air traffic controllers, religious differences are found in the way Type A behavior is associated with several health status indicators. Associations between the Jenkins Activity Survey (JAS) and physical illness incidence, health-promotive behavior, diastolic and systolic blood pressure, subjective distress and impulse control problems, and alcohol consumption are examined by religious attendance, religious affiliation, and change in affiliation. Findings confirm that Type A does not vary significantly by religion. However, there are several significant findings between Type A and various health indicators. Type A is associated with illness incidence, overall and more strongly in several religion, subgroups. Type A and alcohol consumption are related positively in Protestants and converts, and negatively in churchgoing Catholics. Type A is related to impulse control problems in churchgoing Protestants and to subjective distress in churchgoing Catholics. Finally, in individuals with weak or no religious ties, Type A is associated with lower blood pressure. This last finding suggests that in some people (for example, the irreligious or unchurched), the coronary-prone behavior pattern may have cardiovascular effects which are salutary in at least one respect.The authors wish to thank Dr. Kyriakos S. Markides and Laura A. Ray for their assistance with this study. Address requests for reprints to Dr. Levin at the Institute of Gerontology, 300 North Ingalls, Ann Arbor, MI 48109.  相似文献   
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48.
Past research on delinquency and crime has provided convincing data about correlates but not about causes, because it has been largely cross-sectional in design. Whereas cross-sectional research focuses on variations between subjects, longitudinal research can provide information about changes within subjects, which are more important for causes, prevention, and treatment. Many of the most important results in criminology have been obtained in longitudinal or experimental studies, and the major studies of these types are reviewed here. It is now desirable to combine the two methods in a new coordinated program of longitudinal studies including experimental interventions or quasi-experimental analyses. Such projects could study several overlapping cohorts, extend from birth to adulthood, have frequent data collection, and obtain data from a variety of sources about many different types of antisocial behavior.  相似文献   
49.
After outlining the predominant approaches which currently inform student counselling a case is made for adopting a developmental systemic paradigm, locating individual difficulties within the context of a family dilemma. The view is taken that family systems thinking and individual approaches can be complementary and that systemic work need not be restricted to formal family therapy and the technology this implies.  相似文献   
50.
This article presents a simulation-based tutorial system for exploring parallel distributed processing (PDP) models of information processing. The system consists of software and an accompanying handbook. The intent of the package is to make the ideas underlying PDP accessible and to disseminate some of the main simulation programs that we have developed. This article presents excerpts from the handbook that describe the approach taken, the organization of the handbook, and the software that comes with it. An example is given that illustrates the approach we have taken to teaching PDP, which involves presentation of relevant mathematical background, together with tutorial exercises that make use of the simulation programs.  相似文献   
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