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251.
A decade of research and services for homeless mentally ill persons. Where do we stand? 总被引:4,自引:0,他引:4
Over the past decade, researchers have documented the range of needs and devised new methods for increasing our understanding of the homeless severely mentally ill population. Clinicians have developed an appreciation of the difficulty and complexity of effectively treating this population, and policymakers have become increasingly aware of the barriers to developing services and housing. In this article, the progress-to-date in research, the evolution of new service approaches, and the development of federal, state, and local policies to meet the needs of homeless mentally ill individuals are assessed. The many challenges that remain are also considered. 相似文献
252.
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
253.
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
254.
Manifestations, acquisition and diagnostic categories of dental fear in a self-referred population 总被引:2,自引:0,他引:2
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
255.
Resolving Ethical Dilemmas in Management: Experimental Investigations of Values, Accountability, and Choice 总被引:3,自引:0,他引:3
Arthur P. Brief Janet M. Dukerich Lucinda I. Doran 《Journal of applied social psychology》1991,21(5):380-396
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
256.
In two experiments, the accuracy with which subjects detected a conjunction of features was examined as a function of the spacing between items and the goodness of the axis along which they were located. In each array, two items were arranged along a vertical, a horizontal, or a diagonal axis. Based on the well-established oblique effect, the vertical and horizontal axes were considered to be good global patterns and the diagonals were considered to be poor. In Experiment 1, the two items in an array could be two horizontal lines, two vertical lines, a vertical and a horizontal line, or a plus sign with one of the single lines. In Experiment 2, a positive- and a negative-diagonal line were used as the individual features, and an "X" was used as the conjunction. The results from Experiment 1 indicated that global goodness influenced only the rate of illusory conjunctions, and not of feature errors. Illusory conjunctions of vertical and horizontal line segments were more likely to occur in vertical and horizontal arrangements. The results from Experiment 2 revealed a reversal of the effect of global goodness on the rate of illusory conjunctions: Illusory conjunctions of negative- and positive-diagonal line segments were more likely to occur in diagonal arrangements. The results of both experiments taken together showed the existence of an important and new factor that influences the likelihood that features of shape will be conjoined: the ease with which line segments conjoin when they are translated along their extent toward each other. In both experiments, greater spacing between items produced more feature-identification errors and fewer feature-integration errors than did less spacing. 相似文献
257.
W I Grossman 《The Psychoanalytic quarterly》1991,60(1):22-52
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
258.
The effect of flumazenil on acquisition, retention, and retrieval of spatial information. 总被引:1,自引:0,他引:1
J D Brioni M P Arolfo D Jerusalinsky J H Medina I Izquierdo 《Behavioral and neural biology》1991,56(3):329-335
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
259.
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
260.
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