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Observing responses of college students and children of different ages (4 to 5, 9 to 10, and 13 to 14 years) were studied using two-component schedules of reinforcement. Different frequencies or numbers of points were given in the components and points were backed by either money or instructions about getting points (e.g., “points are for the experimenter's information only”). Stimuli that were either correlated or uncorrelated with the components were contingent on presses on either of two concurrently available levers (observing responses). In each of three experiments, preferences for stimuli were consistent with the conditioned-reinforcement hypothesis of observing but inconsistent with the uncertainty-reduction hypothesis. Stimulus preferences were established, eliminated, or reversed by instructions about the significance of getting points not backed with money. Instructions to in effect ignore points with no monetary value eliminated stimulus preference provided that money was not associated with points in other conditions for the same subjects. Stimulus preferences were otherwise independent of monetary point value. Instructions that described reinforcement contingencies promoted more rapid adjustment to the contingencies than occurred without them, and preferences were less variable across sessions within subjects and were on the average more extreme. Although some results involving absolute rates of observing depended upon the age of subjects, stimulus preferences did not. The data suggest that the conditioned-reinforcement hypothesis of observing has considerable generality for humans in choice procedures in the laboratory. That monetary value of points did not affect preferences in a graded fashion is consistent with versions of the conditioned-reinforcement hypothesis which emphasize reduction in delay to reinforcement over other reinforcement parameters.  相似文献   
43.
The influence of perceived somatotype on stereotypes of behavior associated with body build was investigated among 160 male and 140 female Nigerian children in secondary school. In both groups, the perception of subjects' own physiques and discrepancy between their perceived and preferred physiques significantly explained the variance in the character trait scores attributed to body types. In general, the subjects attributed positive character traits to their perceived somatotypes and undesirable traits to the physiques with which they were dissatisfied. Thus, the perception of somatotype and discrepancy between perceived and preferred physique could significantly differentiate the character traits attributed to body build among male and female children.  相似文献   
44.
The effects on aggressive behavior, open-field activity, and pain threshold of bilateral microinjections of serotonin (20 micrograms) and quipazine (20 micrograms), the direct serotonergic receptor agonist, into the cortico-medial amygdala were investigated in Wistar rats. Both drugs significantly prolonged the attack latency in isolated killer rats (predatory aggression model), and suppressed the incidence of aggressive postures/attacks in shock-induced fighting test (affective aggression). The only difference in the open-field behavior was the lower number of central square entries in drug-treated compared to saline-injected rats. None of the substances produced any significant change in jump threshold. It is concluded that stimulation of serotonin receptors within the amygdala produces inhibition of affective and muricidal behavior in isolated rats. The effect does not seem to be dependent on changes in general activity and pain sensitivity.  相似文献   
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A modification in scoring the ABC Scale   总被引:1,自引:0,他引:1  
The scoring procedures for the Articulation of the Body-Concept (ABC) Scale to use with three-, four- and five-year-old children were modified to determine their degree of field-dependence-independence. A total of 300 children, who obtained a score of one or better on the ABC Scale, were administered the Preschool Embedded Figures Test (PEFT) and the ABC Scale. The ABC Scale was scored using its scoring procedures and the scoring procedures for the Goodenough-Harris Drawing Test (GHDT). Scores on the PEFT, ABC Scale and GHDT were correlated with each other. Correlations among all cognitive measures ranged from .88 to .99, which were high and statistically significant (p < .0001). Therefore, the scoring procedures for the GHDT can be substituted in scoring the ABC Scale in assessing young children's field-dependence-independence.  相似文献   
47.
The major purpose of this study was to investigate aphasic patients' STM for visual stimuli which are difficult to encode. The effect of a varied information rate and information load per item was tested, and so was the relation between primacy and recency scores. The investigation included memory both for content and for position. Each item group in the tests consisted of a time sequence of squares with internal grid lines and a dot in one of the cells. The location of the dot had to be remembered. Both the aphasic group and the control group included 24 persons matched for age. The aphasic group showed a somewhat lower overall score than the normal group. Apart from the interaction between groups and information load, no signifcant interactions were observed. However, there was a systematic tendency over tests towards a relatively lower recency score in the aphasic group.  相似文献   
48.
Microcomputer-assisted relaxation   总被引:1,自引:0,他引:1  
The present pilot study was designed to test the effectiveness of a microcomputer program developed by the authors to induce relaxation and focused attention, which are common to most clinical stress-reduction and hypnotic procedures. A nonclinical sample of 20 adults used the program on an APPLE IIc computer in two 30-min. sessions in a within-subjects design. Repeated measures analyses of variance showed significant decreases in the Spielberger State Anxiety Scale and on a visual analog anxiety scale. Limitations and implications of the study are discussed.  相似文献   
49.
This project studied the effects of weather variables and size of the population on minor and major violence rates within six prisons in the Kingston, Ontario, Canada area from January, 1980 through December, 1983. While weather variables have been studied in relation to mood changes within the general population, this study was the first to analyze the impact of weather variables on rates of violence within the prison setting using forward inclusion multiple regression. Analysis showed that population size consistently appeared positively correlated with assaults on other inmates among the male medium-security prisoners during the summer months. In the summer months, temperature tended to be positively related to some minor kinds of offenses, but in the winter months the relationship was negative. Humidity, rain, sunshine hours, snow, and snow on the ground were not consistently related to incidences of minor and major violence. Indices of geomagnetic disturbances had statistically significant inverse relationships with attempted suicide/self-inflicted injury rates among the male prisoners during the summer months. Over 12 months, wind was generally negatively correlated with incidences of major and minor violence among the male inmates. For 6-mo. periods, wind was generally positively correlated with violence rates during the winter months and negatively correlated during the summer months among the male inmates. The findings relating weather variables to violence rates in the women's prison were consistently in opposition to those found for male prisoners during the 4-yr. period.  相似文献   
50.
For four of six autistic children who underwent intensive behavioral treatment, the nature of their self-stimulatory behavior changed from initial lowlevel motor behaviors (such as rocking, spinning, twirling) to differing kinds of higher-level behaviors (such as lining of objects, echolalic speech, and preoccupation with spelling and numerical values). The children who changed to the highest levels of self-stimulatory behavior also showed the largest gains in treatment (as determined by IQ scores, school placement, etc.). The changes in self-stimulatory behaviors were attributed to the intense teaching of appropriate social behaviors and the explicit therapeutic suppression of low-level, self-stimulatory behaviors. The long-term therapeutic effects of changing from lower-to higher-level forms of self-stimulatory behavior were discussed.This study was supported by a grant from the National Institute of Mental Health (grant MH 11440). We want to express our thanks to the parents who allowed us to study their children. We gratefully acknowledge the assistance of Maria Audero with the design of the weighted measure, and Tracee Parker with the collection of the data.  相似文献   
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