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251.
An experiment is reported designed to test the hypothesis that female rats might discriminate between males that differed in the quantity of odor deposited by scent marking. Male odor donors were selected by prior screening for high or low rates of scent marking in an open arena. Females were then tested to determine whether they showed any preference for males that marked at a high rate. It was found that female rats did discriminate, but that they preferred to remain near males selected for low rates of scent marking.  相似文献   
252.
Preprogramming vs. on-line control in simple movement sequences   总被引:1,自引:0,他引:1  
In the present experiment the acceleration traces produced during a repetitive arm extension/flexion movement were measured in addition to the RT required to initiate such a movement. The speed at which this task was completed as well as the number of extension/flexion segments were varied to allow for either preprogramming or on-line control. Evidence from the acceleration traces and the RT data suggested that the movements completed as quickly as possible were preprogrammed; whereas, those completed more slowly were controlled on-line. Furthermore, the topologies of the power spectral density functions from the acceleration traces of each type of movement displayed characteristics typical of these forms of control.  相似文献   
253.
A modified form of Nathanson and Becker's (1983) Health Belief Model Questionnaire and other measures designed to assess cognitive processing were administered to low-income black adolescent female clients of an inner-city comprehensive health care clinic. The purpose of the study was to explore determinants of sexual activity and contraceptive use. Subjects were classified as not sexually active (n = 50), sexually active/noncontracepting (n = 20), or sexually active/contracepting (n = 72). Not sexually active subjects tended to be younger, more career motivated, to have a father at home, to be more influenced by family values, and to have more conservative attitudes regarding adolescent sexuality than did sexually active subjects. Sexually active/noncontracepting subjects tended to report fewer benefits and more barriers to the use of contraception. Level of cognitive processing did not differ among the three groups, but was at a lower-than-expected level for age. Finally, inconsistent contraceptive use was common to both sexually active groups.  相似文献   
254.
As an essential contributor to the scientific understanding of mental health and illness, psychology continues to be the leading discipline receiving National Institute of Mental Health (NIMH) research support. Future behavioral science research initiatives at NIMH are likely to emphasize cognitive science, behavioral genetics, behavioral patterns and physiological systems, and personality, motivation, emotion, and interpersonal processes. Although prognostication is particularly risky in times of transition such as the present, advocacy efforts focused on mental-illness-related research are most likely to help the NIMH and the field if they avoid polarization and factionalization by providing equal encouragement for studies of biological aspects, of behavioral aspects, and of their interaction.  相似文献   
255.
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   
256.
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   
257.
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   
258.
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   
259.
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   
260.
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   
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