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121.
The behavioral effects of d-amphetamine sulfate were studied in adult male stumptail macaques living within a large heterogeneous group in an outdoor enclosure. Among five subjects that received a range of doses (.01 to .3 mg/kg), d-amphetamine increased self-aggressive behavior and abnormal posturing in subjects that exhibited these types of behavior prior to drug administration, but it had no effect in subjects not exhibiting those activities in the absence of the drug. For the former subjects, the dose-effect curves for self-aggression were of an inverted U-shape analogous to the effect of d-amphetamine on schedule-controlled behavior. Over the range of doses studied, the curve for abnormal posturing was monotonic. The data indicate that d-amphetamine can have effects on untrained behavior in individual animals in a quasinatural environment that are qualitatively and quantitatively similar to the behavioral effects observed in other laboratory environments, and that d-amphetamine does not evoke or increase a behavioral response in individual subjects that do not exhibit the response in the absence of the drug.  相似文献   
122.
If spatial memory tasks are considered as foraging problems, it can be predicted that rats' difficulty in learning a win-stay task—revisiting part of a maze where food has recently been found—should be partly overcome if the food is not fully consumed at the first visit (nondepleted reward) rather than being all eaten (depleted reward). Three experiments confirmed and further analysed this result. Experiments 1 and 2 showed that it does not depend on the amount of food initially found; nor is win-stay performance affected by the amount of food actually eaten. Experiment 3 suggested that the effects of nondepleted reward are mainly due to the animals' being interrupted while eating, and very little to the fact that uneaten food is left behind. The results are discussed with regard to their implications for learning theory, and for the application of foraging theory to learning and memory experiments.  相似文献   
123.
Choice reaction latencies were measured at three different a priori probabilities for two stimulus alternatives. Unlike the results of some other studies, the mean latency of a given response was nearly the same whether the response was correct or incorrect. The discriminable stimuli were a 1000- or a 1700-Hz tone presented at 70 dB SPL. Latencies and standard deviations, based on about 17,000 observations, are reported for three observers. The data are compared with predictions of the optimum sequential model of Wald and Stone and two modifications of that random-walk model, one proposed by Link and Heath and the other proposed by Laming. Fast-guess analyses were also carried out. The three-parameter version of either the sequential or the modified random-walk models provided reasonably accurate predictions of the mean data for each observer. The parameters estimated by the fast-guess analysis were unrealistic. There are three obvious differences between this experiment and most previous choice reaction-time experiments. First is stimulus modality#x2014;we used an auditory signal, whereas most of the previous studies used a visual signal. Second, the observers practiced more in this experiment than in most previous experiments. Finally, there was a random foreperiod with a heavy penalty for anticipations. One or more of these factors is the probable reason for the discrepancy between our results and those of previous studies.  相似文献   
124.
A complex in-basket simulation and a paper-and-pencil scenario experiment were used to study relationships between organizational leadership and gender. Separate samples completed identical attitude instruments in the independent studies. Analysis revealed that substantially more of the total variance was accounted for in the simulation study than in the scenario investigation. Also, more overt, gender-based responses were observed in the scenario study. It was concluded that social simulation may tap a deeper level of psychological process and may elicit more subject involvement than typical experimental methods. Thus, the more complex procedures of the simulation, as compared to those of a typical method such as a scenario study, are justified in the study of organizational behavior.  相似文献   
125.
The discussions which follow rest on a distinction, first expounded by Husserl, between formal logic and formal ontology. The former concerns itself with (formal) meaning-structures; the latter with formal structures amongst objects and their parts. The paper attempts to show how, when formal ontological considerations are brought into play, contemporary extensionalist theories of part and whole, and above all the mereology of Leniewski, can be generalised to embrace not only relations between concrete objects and object-pieces, but also relations between what we shall call dependent parts or moments. A two-dimensional formal language is canvassed for the resultant ontological theory, a language which owes more to the tradition of Euler, Boole and Venn than to the quantifier-centred languages which have predominated amongst analytic philosophers since the time of Frege and Russell. Analytic philosophical arguments against moments, and against the entire project of a formal ontology, are considered and rejected. The paper concludes with a brief account of some applications of the theory presented.  相似文献   
126.
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   
127.
Male sexual fantasy: multidimensionality in content   总被引:2,自引:0,他引:2  
Sixty-six men provided ratings of the extent to which they regarded fantasies depicting nominated sexual activities as sexually arousing. A Male Sexual Fantasy Questionnaire (MSFQ) with five subscales was constructed following factor analysis of these ratings. The subscales yield separate scores for fantasies representing sensual, genital, public sex, sexual dominance-submission, and sexual aggression themes. Levels of penile tumescence recorded while men engaged in fantasies depicting content represented in the MSFQ correlated with the extent to which these men earlier had rated these same fantasies as sexually arousing. Since ratings on the MSFQ did not correlate substantially or consistently with scores on the Betts Questionnaire Upon Mental Imagery, the Imaginal Processes Inventory, and the Gordon Test of Visual Imagery Control, sexual fantasy may be mediated by processes different from those involved in non-sexual imagery and daydreaming. The need to validate use of the MSFQ in several clinical contexts is noted.  相似文献   
128.
Chronic illnesses such as rheumatoid arthritis (RA) have been linked to poor psychological adjustment, although individual differences in this relationship have been observed. This study examines the role of perceived competence as a mediator between RA and adjustment. Persons with RA (N= 208) were surveyed three times at 6-month intervals concerning several potential antecedents of adjustment (pain, psychosocial impairment, social support, and control beliefs), self-perceived level of competence, and level of adjustment (life satisfaction and depressive symptomatology). Within each observational period strong evidence was obtained for perceived competence as a mediator of adjustment. Longitudinally (across the year) the data were consistent with a mediational model, but strong evidence establishing mediation was not obtained. Implications of these findings, and the importance of examining the role of perceived competence in adaptation to chronic illness, are discussed.  相似文献   
129.
Children have difficulty learning to read alphabetic writing systems, in part, because they have difficulty segmenting spoken language into phonemes. Young children also have difficulty attending to the individual dimensions of visual objects. Thus, children's early difficulty in reading may be one sign of a general inability to selectively attend to the parts of any perceptual wholes. To explore this notion, children in kindergarten through fourth grade (Experiments 1, 3, and 4) and adults (Experiment 2) classified triads of spoken syllables and triads of visual objects. Classifying speech by common parts was positively related to reading and spelling ability (Experiments 1 and 4), but usually not to classifying visual stimuli by common parts under free classification instructions (Experiments 1 through 3). However, classification was more consistent across the visual and auditory modalities when the children were told to classify based on a shared constituent (Experiment 4). Regardless of instructions, performance on the visual tasks did not usually relate to reading and spelling skill. The ability to attend selectively to phonemes seems to be a "special" skill--one which may require specific experiences with language, such as those involved in learning to read an alphabetic writing system.  相似文献   
130.
Research in bulimia has flourished in recent years, and yet minimal attention has been devoted to explorations of the bulimic's basic personality organization. We utilized the Rorschach to differentiate between purging and nonpurging bulimics and controls. There were 15 subjects in each group. The Comprehensive System (Exner, 1986) was used for the scoring of the protocols. Statistically significant differences were not found between the two bulimia groups, but interesting trends were detected in the areas of depression, anger, and self-preoccupation. Results appear to be constrained by the low rate of purging behavior. Comparisons between the combined bulimia groups and the controls resulted in solidly characterizing the bulimics as displaying perceptual inaccuracies, disordered thinking, a vulnerability to interpersonal problems, a damaged self-image, and a pessimistic outlook. The strengths of the study were its use of the Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev. [DSM-III-R]; American Psychiatric Association, 1987) nonpatients bulimic subtypes and a control group that was comparable in terms of demographics. Future Rorschach studies with bulimics displaying higher frequencies of binging and purging behaviors are suggested.  相似文献   
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