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251.
I A Friedman 《Adolescence》1991,26(104):967-976
This study explored the concerns of Israeli adolescents, who grow up in a socially, politically, and economically highly stressed environment. Ninth- and eleventh-grade students (N = 1,645) completed a questionnaire in which they indicated three important problems they had recently experienced. Content analysis identified six major categories of concerns (listed in descending order of occurrence): studies and career, social "I," personal "I," existential issues, army or national service, and health and drugs. Younger adolescents were found to be more concerned with problems involving studies and career and with issues pertaining to the social "I"; older adolescents were more concerned with existential issues and army or national service. Boys were more concerned with existential issues, army or national service, studies and career, and the social "I." Girls were more concerned with issues pertaining to the personal "I." Three major sources of advice were identified: friends, parents, and brothers/sisters.  相似文献   
252.
The concept of invariant relative timing has typically been associated with the concept of a generalized motor programme. The present study approaches the phenomenon of invariant relative timing from the perspective of learning. The underlying question of concern for this study was, "What is learned." The specific question was whether relative timing is one of the essential properties of movement that is learned during skill acquisition. In the present experiment, subjects were given extensive practice in learning to track and reproduce a criterion waveform using a joystick control for their response. In order to test whether subjects learn the relative timing of a movement, they were transferred to tracking waveforms that were identical to the criterion in terms of relative timing, but different in terms of absolute timing. Measurements were taken on all waveforms in two conditions: (a) in a pursuit tracking condition where subjects were temporally constrained by the stimulus, and (b) in a reproduction condition where subjects' timing was not constrained. The outcome from both conditions gives support to the idea that humans learn invariant relative timing during the acquisition of a motor skill.  相似文献   
253.
This study aimed to clarify how manifestations and acquisition relate to diagnostic categories of dental fear in a population of self-referred dental fear patients, since diagnostic criteria specifically related to dental fear have not been validated. DSM III-R diagnostic criteria for phobias were used to compare with four existing dental fear diagnostic categories, referred to as the Seattle system. Subjects were 208 persons with dental fear who were telephone interviewed, of whom a subsample of 155 responded to a mailed Dental Anxiety Scale (DAS), State-Trait Anxiety Inventory and a modified FSS-II Geer Fear Scale (GFS). Personal interviews and a Dental Beliefs Scale of perceived trust and social interaction with dentists were also used to evaluate a subsample of 80 patients selected by sex and high dental fear. Results showed that the majority of the 80 patients (66%), suffered from social embarrassment about their dental fear problem and their inability to do something about it. The largest cause of their fear (84%) was reported to be traumatic dental experiences, especially in childhood (70%). A minority of patients (16%) could not isolate traumatic experiences and had a history of general fearfulness or anxiety. Analysis of GFS data for the 155 subjects showed that fear of snakes and injuries were highest among women; heights and injections among men. Fear of blood was rarely reported. Spearman correlations between GFS individual items and DAS scores indicated functional independence between dental fear and common fears such as blood, injections and enclosures in most cases. Only in specific types of dental fear did these results support Rachman and Lopatka's contention that fears are thought to summate.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
254.
Hypotheses regarding the effects of personal values and accountability on the resolution of ethical dilemmas in management were formulated and tested experimentally with a sample of 135 M.B.A. students. Personal values were found to be related to how subjects chose to resolve an ethical dilemma presented to them; but, as expected, this relationship did not hold when subjects were made to feel accountable to another for their choices. Accountability, unexpectedly, however, did not have a main effect on choices. This lack of an effect tentatively was attributed to the inexplicitness of the accountability manipulations. In a second and third experiment, support for the importance of explicitness in accountability research was obtained. The theoretical and practical implications of the findings from all three experiments were discussed.  相似文献   
255.
Traumatized infants and children may exhibit syndromes of aggressive, pain-seeking, and self-destructive behavior resembling the so-called sadomasochism seen in adults. Three hypotheses are offered to account for the repetition of sadomasochistic phenomena in childhood and later character disorders: 1) pain and painful affects are sources of aggression; 2) the need to control aggression plays an important role in the development of psychic structure; 3) child abuse and trauma impair the ability to use fantasy for the mastery of impulses. Difficulty in expression and control of aggression are central issues in character disorders.  相似文献   
256.
The effect of flumazenil, a benzodiazepine-receptor antagonist, was evaluated in a spatial-reference memory procedure in a water maze. Flumazenil (1.0, 3.0, and 10.0 mg/kg, ip) did not modify acquisition of spatial information. Retention was similar between control and experimental rats 24 h after the training phase, as all groups showed bias to the target quadrant in a free swim trial. However, 10 days later, only flumazenil-injected rats (3.0 mg/kg) showed bias to the target quadrant. Flumazenil did not affect retrieval of spatial information in a group of well-trained rats. These results suggest that a benzodiazepine-receptor mediated endogenous mechanism is activated during learning of spatial tasks and that its blockade facilitates retention of spatial information.  相似文献   
257.
To begin studying the neural basis of higher-order decision-making in Aplysia fasciata, we examined individual bouts of behavior in various conditions of access to food and/or mates. We then determined rules governing transitions between bouts. The data indicate that a single intermediate condition, moving in place, may be centrally related to transitions between behaviors. In all conditions, over 85% of all transitions between behaviors were via moving in place. Moving in place tended to precede and follow other categories of activity (crawling, swimming, immobile), and feeding. Also, moving in place apparently represents a fixed proportion of all bouts of behavior. In each condition, moving in place represented approximately 40% of all bouts, while the number of bouts of other behaviors varied markedly. After a bout of moving in place there was a strong tendency for the animal to return to the behavior performed before moving in place. Additional preferred sequences of behavior were also seen. Courtship tended to precede mating, and crawling preceded swimming.  相似文献   
258.
The presence of other Aplysia in the environment increases the time spent feeding. This finding is consistent with the hypothesis that a common arousal mechanism modulates feeding and reproductive behaviors. The arousal level is presumably increased by pheromones released by additional animals.  相似文献   
259.
Taking the integrated viewpoints of causal theory of reference, cognitive science and the notion of correspondence principles from physics, this paper addresses the problems of creativity, the nature of visual imagery and the manner in which science progresses.  相似文献   
260.
Attractiveness ratings of 50 children aged 12–38 months were investigated in relation to adult socializing agents' behavior toward the children in their homes and play groups and their attitudes toward the children. Attractiveness scores were derived from 43 judges' ratings of facial photographs of the children. The same children were observed in play groups with female care givers; 40 of them were also observed in their homes with their parents. Play-group care givers rated the children for likability, tractability, and peer relations. Parents rated their attitudes toward giving routine care to their child. Attractiveness scores were not correlated with any adult attitude measures. Girls' attractiveness scores were positively correlated with their attempts to communicate in home and play group, and with mothers', fathers', and care givers' instructional responses, but negatively correlated with passive behavior in the home and with mothers' positive reactions. Boys' attractiveness scores were negatively correlated with passive behavior in the play group; no other significant correlations were found in the data for boys.  相似文献   
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