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281.
Much research on emotional facial expression employs posed expressions and expressive subjects. To test the generalizability of this research to more spontaneous expressions of both expressive and nonexpressive posers, subjects engaged in happy, sad, angry, and neutral imagery, and voluntarily posed happy, sad, and angry facial expressions while facial muscle activity (brow, cheek, and mouth regions) and autonomic activity (skin resistance and heart period) were recorded. Subjects were classified as expressive or nonexpressive on the basis of the intensity of their posed expressions. The posed and imagery-induced expressions were similar, but not identical. Brow activity present in the imagery-induced sad expressions was weak or absent in the posed ones. Both nonexpressive and expressive subjects demonstrated similar heart rate acceleration during emotional imagery and demonstrated similar posed and imagery-induced happy expressions, but nonexpressive subjects showed little facial activity during both their posed and imagery-induced sad and angry expressions. The implications of these findings are discussed. 相似文献
282.
Retrospective coding in pigeons' delayed matching-to-sample 总被引:2,自引:0,他引:2
P J Urcuioli T R Zentall 《Journal of experimental psychology. Animal behavior processes》1986,12(1):69-77
In this study we examined how coding processes in pigeons' delayed matching-to-sample were affected by the stimuli to be remembered. In Experiment 1, two groups of pigeons initially learned 0-delay matching-to-sample with identical comparison stimuli (vertical and horizontal lines) but with different sample stimuli (red and green hues or vertical and horizontal lines). Longer delays were then introduced between sample offset and comparison onset to assess whether pigeons were prospectively coding the same events (viz., the correct line comparisons) or retrospectively coding different events (viz., their respective sample stimuli). The hue-sample group matched more accurately and showed a slower rate of forgetting than the line-sample group. In Experiment 2, pigeons were trained with either hues or lines as both sample and comparison stimuli, or with hue samples and line comparisons or vice versa. Subsequent delay tests revealed that the hue-sample groups remembered more accurately and generally showed slower rates of forgetting than the line-sample groups. Comparison dimension had little or no effect on performance. Together, these data suggest that pigeons retrospectively code the samples in delayed matching-to-sample. 相似文献
283.
T R Zentall P Jackson-Smith J A Jagielo G B Nallan 《Journal of experimental psychology. Animal behavior processes》1986,12(2):153-159
Categorical coding is the tendency to respond similarly to discriminated stimuli. Past research indicates that pigeons can categorize colors according to at least three spectral regions. Two present experiments assessed the categorical coding of shapes and the existence of a higher order color category (all colors). Pigeons were trained on two independent tasks (matching-to-sample, and oddity-from-sample). One task involved red and a plus sign, the other a circle and green. On test trials one of the two comparison stimuli from one task was replaced by one of the stimuli from the other task. Differential performance based on which of the two stimuli from the other task was introduced suggested categorical coding rules. In Experiment 1 evidence for the categorical coding of sample shapes was found. Categorical color coding was also found; however, it was the comparison stimuli rather than the samples that were categorically coded. Experiment 2 replicated the categorical shape sample effect and ruled out the possibility that the particular colors used were responsible for the categorical coding of comparison stimuli. Overall, the results indicate that pigeons can develop categorical rules involving shapes and colors and that the color categories can be hierarchical. 相似文献
284.
Sex differences in the effects of gonadectomy on amphetamine-induced rotational behavior in rats 总被引:2,自引:0,他引:2
The effects of gonadectomy on amphetamine-induced rotational behavior were studied in male and female rats. Different systemic doses were used to produce equivalent brain concentrations of the drug in each group, thereby controlling for sex differences in the metabolism of amphetamine. Ovariectomy of female rats significantly attenuated amphetamine-induced rotation, whereas castration of males was without effect. The results support the idea that in females, the endogenous gonadal hormones facilitate functional activity in the mesostriatal dopamine system. 相似文献
285.
286.
Stress and coping in early adolescence: relationships to substance use in urban school samples 总被引:5,自引:0,他引:5
T A Wills 《Health psychology》1986,5(6):503-529
Measures of stress and coping were obtained from two cohorts of urban adolescents during the seventh- to eighth-grade period and were related to indices of cigarette smoking and alcohol use. Predictions were derived from a stress coping model of substance use. Stress was indexed by measures of subjective stress, recent events, and major life events; coping was assessed by behavior-based and intention-based methods. Concurrent and prospective analyses were consistent with predictions, indicating that stress was positively related to substance use, and four coping mechanisms (behavioral coping, cognitive coping, adult social support, and relaxation) were inversely related to substance use. Two types of predicted interactions, Stress X Coping and Positive X Negative Events, were found. Measures indexing peer support, distraction coping, and aggressive coping were positively related to substance use, independent of other predictors. Implications for substance use theory and prevention research are discussed. 相似文献
287.
T O Nelson R J Leonesio R S Landwehr L Narens 《Journal of experimental psychology. Learning, memory, and cognition》1986,12(2):279-287
Distinctions are drawn between different predictors of an individual's memory performance, with emphasis on the notion of privileged access to idiosyncratic knowledge. Research is reported in which undergraduates attempted to recall the answers to general-information questions, then made feeling-of-knowing judgments on nonrecalled items, and subsequently had a criterion test (relearning, perceptual identification, or one of two versions of recognition). For predicting an individual's criterion performance, the individual's own feeling-of-knowing predictions were intermediate between two kinds of normative predictions: The individual's feeling-of-knowing predictions were more accurate than predictions derived from normative feeling-of-knowing ratings but were less accurate than predictions derived from base-rate item difficulty (normative probabilities of correct recall). Subsidiary analyses showed that factors other than unreliability are responsible for the partial inaccuracy of the individual's feeling of knowing. Ramifications are discussed for possible ways to improve the accuracy of an individual's feeling-of-knowing predictions. 相似文献
288.
289.
Dating experiences, especially the type or stage of dating, have consistently been found to be related to premarital sexual behavior. Findings regarding the age at 1st date and sexual behavior have been less consistent. This paper examined the age at which dating began and the type of dating relationship as correlates of premarital sexual attitudes and behavior among mid-teen adolescents. The analyses were based on a sample of high school students (n=836), most of whom were between the ages of 15 and 18 when the surveys were conducted. Early dating, especially early steady dating, was related to permissive attitudes and to premarital sexual experience among both males and females. The relationship between early dating and intercourse experience was particulary strong among Mormons, a religious group which has institutionalized age 16 as the legitimate age to begin dating. 相似文献
290.
Inpatient Multimodal Therapy (imt) is a residential treatment program, lasting a maximum of 36 weeks, for patients with severe neurotic symptoms. A group of
44 chronic obsessive-compulsive patients and a group of 40 chronic phobic patients were treated in order to assess the outcome
and the process of treatment and to identify prognostic factors associated with the effect. At follow-up—on average, eight
months after discharge—it was found that 60% had improved, 32% had remained the same, and 8% had deteriorated, indicating
that, in general, the treatment was beneficial. That these effects were long-lasting is supported by the fact that, at follow-up,
78% of all patients were no longer receiving treatment, 18% were receiving outpatient or day treatment, and 4% were receiving
inpatient treatment. Phobic patients appear to have gained more from the multimodal approach than did obsessive-compulsive
patients, as indicated by the fact that the severity of symptoms decreased as they improved in rational thinking, assertiveness,
and arousal. By contrast, obsessive-compulsive patients relapsed more than phobic patients did. This was attributed to the
fact that the former gained less from the rational-emotive training, denied problems with assertiveness, and did not practice
the acquired relaxation skills. It further appeared that a favorable outcome could be induced in patients who (1) expressed
relatively mild symptoms in this otherwise severe group, (2) reported relatively few additional complaints, (3) could clearly
indicate interpersonal problems, and (4) did not use psychotropic drugs. These prognostic factors are so widespread that not
much weight can be ascribed to them. Yet they are useful for indication ofimt until better predictors are found. 相似文献