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911.
Administered the Indian adaptation of the Rosenzweig P-F Study to 144 Scheduled Caste (SC) adolescent and 158 young adult male Indians. The results show that SC adolescents scored significantly higher on ego-defensive (ED) and extragressive (EA) and lower on need-persistive (NP), introgressive (IA) and imgressive (MA) reactions as compared to the Non-Scheduled caste (Non-SC) adolescents while there was no significant difference on any reaction among SC and Non-SC young adults. SC adolescents scored higher on NP and lower on obstacle-dominance (OD) reaction as compared to the SC young adults. Non-SC young adults were higher on EA, ED, and OD and lower on IA and NP as compared to those of adolescents. The pattern of reactions was ED-EA-NP-IA-MA-OD among adolescents and ED-EA-IA-NP-MA-OD among young adults of both the castes.  相似文献   
912.
An attempt was made to test the hypothesis that the Egocentricity Index (Exner, 1974), a ratio which incorporates pair and reflection responses, is related to self-esteem. Sixty criminal defendants referred for psychiatric evaluation were routinely administered the Rorschach. After all other testing was completed the subjects were asked to complete the Coopersmith Self-esteem Inventory. Results found no significant relationships between the Egocentricity Index and self-esteem as measured by the Coopersmith. It was recommended that the Egocentricity Index not be used as a measure of self-esteem until research evidence to support its use in this manner is provided.  相似文献   
913.
Alcohol and social behavior II: the helpful drunkard   总被引:2,自引:0,他引:2  
Can alcohol make people more helpful, and if so, how? We hypothesized that alcohol would increase helping when, if the person were sober, the helping response would be under high inhibitory conflict--that is, when it would be affected by strong instigating and inhibiting pressures. Alcohol's damage to inhibitory processing should then allow instigating pressures to have more influence on the response, increasing helping. We expected that under low inhibitory conflict, when either or both of these response pressures would be weak under sobriety, alcohol would have little effect on helping. In two experiments we examined this reasoning. In Study 1, a mild dose of alcohol increased helping among high-conflict subjects pressured to help with a task they did not like, but did not increase helping among low-conflict subjects who either liked the task or were weakly pressured to help. In Study 2, a somewhat stronger dose of alcohol increased helping among all high-conflict subjects pressured to help with an undesirable task, yet again had no effect among low-conflict subjects weakly pressured to help. These studies provided an experimental demonstration of the role of inhibitory response conflict in mediating alcohol's social effects, and show that this process generalizes to prosocial behavior. Additional evidence from both experiments helped to rule out alternative explanations concerning drinking expectancies, alcohol's ability to enhance mood, and its ability to make the task more bearable.  相似文献   
914.
Historically, women and minority group members have been underrepresented in the professions and in better paying, high-status jobs. Even when they have been admitted to such positions, these underrepresented persons often have been the only member of their social category: a token. Previous field and laboratory research has shown that "tokens" attract disproportionate attention and are either evaluated unfairly or evaluated on the basis of their normal reactions to differential treatment by majority group members. We tested the possibilities of whether tokens might suffer more cognitive deficits than would nontokens, and whether they do so even when they are treated no differently. College students were led to believe that they were sharing their views on everyday topics with three other students (actually videotaped confederates), who were either all of the student's own sex or all of the opposite sex. In a later memory test, token participants remembered fewer of the opinions that they and the three other students had expressed than did nontokens. Observers, in contrast, remembered more of what token subjects said than what the three other students said. Theoretical and public policy implications are discussed.  相似文献   
915.
Models are sometimes developed on the premise that there are no differences between two or more conditions regardless of experimental manipulation. This article argues that unless a very sensitive experiment (or series of experiments) was conducted, such conclusions are often premature. Design and statistical factors such as alpha level, variability, sample size, and treatment effect are all determinants of the sensitivity of the experiment. It is sometimes the case that an experiment produces differences between means and yet the null hypothesis is not rejected because of high variability within experimental conditions or because too few subjects were used. Unless the probability of detecting a difference between groups is known, it would seem unwise to conclude that no difference exists. Judgment on the model should be suspended. Examples are taken from the mass-spring and pulse-step models fro voluntary movement control to illustrate the problem.  相似文献   
916.
A detailed kinematic and electromyographic (EMG) analysis of single degree of freedom timing responses is reported to (a) determine the coherence of kinematic and EMG variability to the reduced timing error variability exhibited with amplitude increments within a given criterion movement time and (b) understand the temporal organization of various movement parameters in simple responses. The data reveal that the variability of kinematic (time to peak acceleration, duration of acceleration phase, time to peak deceleration) and EMG (duration of agonist burst, duration of antagonist burst, time to antagonist burst) timing parameters decreased with increments of average velocity in a manner consistent with the variable timing error. In addition, the coefficient of variation for peak acceleration, peak deceleration, and integrated EMG of the agonist burst followed the same trend. Increasing average movement velocity also led to decreases in premotor and motor reaction times. Overall, the findings suggest a strong coherence between the variability of response outcome, kinematic, and EMG parameters.  相似文献   
917.
This study was designed to identify the phase of rapid aimed movements responsible for hand differences in motor skill, and to evaluate potential differences between the hands in accommodating to greater accuracy demands. In both experiments, an accelerometer mounted on a stylus allowed key changes in acceleration to be used to partition the movement into phases. In Experiment 1, slower left hand movement times were attributable primarily to a terminal homing-in phase, especially as target size decreased. Since error rates varied as a function of hand and target size, speed-accuracy trade-offs may have occurred. Experiment 2 rigidly controlled error rate and confirmed the major hand difference to occur in the latter phase of the movement where error correction is presumed. Although less pronounced, adjustments were made in the earlier movement phases as well. Accommodation to greater accuracy demands involved moving the stylus closer to the target before decelerating to engage in error correction. This adjustment to gain enhanced precision was more pronounced in the left hand.  相似文献   
918.
The role played by reflex pathways in the production of movement has been a significant issue for motor control theorists interested in a wide variety of motor behaviors. From studies of locomotion and chewing, it appears that gains in reflex pathways can be altered so that activity in these pathways does not produce destabilizing responses during movement. In speech production, recent experimental evidence has been interpreted to suggest that autogenetic lip reflexes (perioral reflexes) are suppressed during sustained phonation or speech production. The present study was conducted to assess the effects of phonation, direction of movement, and ongoing speech production on reflex responses of lip muscles. The present results suggest, in contrast to earlier work, that this reflex pathway is not suppressed or absent because the amplitude of the observed response depends upon the activation levels of the various muscles of the lower lip and, therefore, indirectly on the nature of the gesture the subject is instructed to produce.  相似文献   
919.
We show that self-ratings by 141 undergraduates on 17 items form a circumplex that closely agrees with Conte and Plutchik's (1981) circumplex of personality traits. The order of items on a circumplex, generated by self-ratings following a here-and-now instruction set, scarcely differs from that of a circumplex representing the same ratings averaged over a 2-week period. The configuration becomes more elliptical as one moves from the state-like measures (here-and-now ratings) to pure trait measures (averages), but measurement bias is shown to be the most probable cause of the distortion. Allowing for the limitations of small samples of items and raters, the findings show that the circumplex model represents a valid theoretical construct and does not arise from measurement error or from an illusory implicit personality theory.  相似文献   
920.
Conditioned placebo responses   总被引:4,自引:0,他引:4  
Following earlier animal research, we attempt to condition placebo effects in human subjects. Four groups of 8 voluntary subjects were told that the experimenters would test a powerful new analgesic cream over three sessions by assessing its ability to reduce experimentally induced pain. The analgesic cream was, in fact, a placebo. In the first session all subjects were tested with and without the cream to assess their placebo response. In the second session, to condition two groups (with differing stimulation levels) to experience pain relief in response to the placebo, we repeatedly paired a reduction in nocioceptive stimulation with placebo administration. (Subjects were unaware that stimulation levels were manipulated). To condition the other two groups (with different stimulation levels) to experience an exacerbation of the pain, we paired an increase in nocioceptive stimulation with placebo administration. In the third session, all subjects were again tested for placebo response. Results suggested that placebo responses are conditionable in the laboratory in both a positive and negative direction. The clinical implications of a learning theory of placebo behavior are discussed.  相似文献   
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