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991.
Lever pressing in rats was maintained by continuous and intermittent schedules of food while defecation was monitored. In Experiment 1, reinforcement densities were matched across variable-ratio and variable-interval schedules for three pairs of rats. Defecation occurred in all 3 rats on the variable-ratio schedule and in all 3 rats on the yoked variable-interval schedule. In Experiment 2, fixed-ratio and fixed-interval schedules with similar reinforcement densities maintained lever pressing. Defecation occurred in 3 of 4 rats on the fixed-ratio schedule and in 4 of 4 rats on the fixed-interval schedule. Almost no defecation occurred during continuous reinforcement in either experiment. These results demonstrate that defecation may occur during both ratio and interval schedules and that the inter-reinforcement interval is more important than the behavioral requirements of the schedule in generating schedule-induced defecation.  相似文献   
992.
In November 1990 the National Institute of Mental Health (NIMH) convened a special conference of over 100 scientists and leaders to outline specific strategies and research initiatives that should be developed to implement the recently released National Plan for Research on Child and Adolescent Mental Disorders.Participants included journal editors, educators from psychology and psychiatry, representatives from private foundations, and leaders of research program areas in public funding agencies. Critical knowledge gaps were identified in five areas of child and adolescent psychopathology, including depression, attention deficit hyperactivity disorder, conduct disorder, the anxiety disorders, and the developmental disorders. For each of these areas, special emphasis was placed on developing new ideas and obtaining critical input from other areas of investigation. This report summarizes the identified research gaps and recommends research initiatives to implement the National Plan, as outlined by the conference participants.  相似文献   
993.
There have been continuing concerns about the extent to which maternal depression may influence maternal reports of child behavior. To examine this issue, a series of structural equation models of the relationships between maternal depression and errors in maternal reports of child behavior was proposed and tested. These models assumed that (a) maternal depression was unrelated to maternal reporting behavior; (b) maternal depression causally influenced maternal reporting accuracy; (c) maternal depression was correlated with reporting accuracy. These models were fitted to data on maternal depression and multipleinformant (mother, teacher, child) reports of conduct disorder and attention deficit behaviors for a birth cohort of 12 and 13yearold New Zealand children. The results of model fitting suggested the presence of small to moderate correlations (@#@ r=+.13 to+.40) between maternal depression and maternal reporting errors, indicating the presence of a tendency for increasing maternal depression to be associated with a tendency for mothers to overreport child behavior problems. However, independently of any effects of maternal depression on maternal reporting errors there was evidence of small but significant associations (r=.10 to .17; p<.05)between maternal depression and child conduct disorder and attention deficit behaviors.This research was funded by grants from the Health Research Council of New Zealand.  相似文献   
994.
Memory & Cognition - The use of different types of partial temporal information is shown to affect dating accuracy and the distribution of errors in event dating. Several different types of...  相似文献   
995.
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997.
This study examines how gender is related to self-evaluations of information to discuss current social and political issues. The sample is one of predominantly white (96%) college graduates. Using alumni samples, we look at how members of four classes that span 20 years evaluate their knowledge to hold conversations on a variety of public affairs issues ranging from the Strategic Defense Initiative to government funding of abortion. We find gender differences, with men perceiving themselves more knowledgeable in conversations and women less so. We raise the possibility that they are “doing gender.” The implications of these findings are explored.  相似文献   
998.
A series of experiments on intersensory facilitation demonstrates that non-informative sound of low to moderate intensity (30/80 dB) facilitates the reaction to a visual stimulus. By manipulating the preprocessing and perceptual stages of the visual signals, it appears that auditory intensity reduces choice reaction time independently from the positive influence of the intensity and duration of the visual imperative signal, but interacts with the effect of stimulus degradation. Degraded stimuli take more profit of the sound than intact stimuli. Besides a short-term activation effect, originated by accessories of the auditory modality, on the motor adjustment stage (cf. Sanders 1983), the results suggest that the accessory influences the stage of feature extraction.  相似文献   
999.
C M Shelton  D P McAdams 《Adolescence》1990,25(100):923-943
Current interest in moral theorizing has been dominated by Kohlberg's cognitive-developmental view. Haan (1982) has challenged psychology's reliance on this rationalistic focus and has argued for a rethinking of morality's meaning in accord with everyday human experience. In light of this challenge, the present study gives both theoretical and empirical support to the advancement of a morality for everyday life. Specifically, a new measure called the Visions of Morality Scale (VMS) is reported. The VMS is sensitive to three dimensions which are necessary for an everyday morality: (1) a human constitutive component which is universally experienced by all human beings (empathy); (2) the inclusion of a behavioral component which reflects actual behavior (pro-social inclinations); and (3) a view of morality that is multilevel (private, interpersonal, and social). A brief sketch of the VMS is provided. Results are presented from a study of 181 high school students which relate the VMS to empathy and political orientation. Highly significant relationships were found among morality, political orientation, and empathy. In addition, results revealed numerous sex differences. Finally, the implications of an everyday morality are discussed.  相似文献   
1000.
Previous research on homeless adolescents has largely ignored the distinction between those who have left home on their own volition (runaways), and those who have been forced to leave (throwaways). Fifty-two homeless adolescents in Brisbane, Australia, were assessed to compare male and female runaways and throwaways for social adjustment and symptomatology. Differences for social adjustment (antisocial tendencies and aggression) and symptomatology (social isolation and depression) were predicted. Results indicated that male runaways were significantly more hostile than male throwaways (p less than .001), and significantly more socially isolated than female runaways (p less than .025). Female throwaways, however, were significantly more hostile than male throwaways (p less than .025) and female runaways (p less than .025). Yet homeless males overall had a significantly stronger urge to act out hostility than homeless females (p less than .025). In addition, female throwaways were significantly more antisocial than male throwaways (p less than .001). There were no significant differences for depression. A theory of inner social control (Hirschi, 1969), postulating absence of bonding in earlier socialization, was supported.  相似文献   
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