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981.
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
982.
Adolescent self-disclosure and loneliness: private self-consciousness and parental influences 总被引:4,自引:0,他引:4
Using structural equation techniques, we tested a theoretical model designed to describe the causal relations existing among loneliness, self-disclosure to peers and parents, and specific antecedent variables. Participants were 350 high-school students who answered questions concerning themselves and their interpersonal relationships. Results generally indicated a good fit between the theoretical model and the observed relations. In addition to replicating the findings of previous studies concerning the relation between self-disclosure and loneliness, results also indicated an indirect relation between private self-consciousness and loneliness via peer self-disclosure; that is, high private self-conscious adolescents' greater willingness to self-disclose to peers resulted in their feeling less lonely. Results are discussed in terms of current theory in related fields. 相似文献
983.
S Strack P H Blaney R J Ganellen J C Coyne 《Journal of personality and social psychology》1985,49(4):1076-1085
Three studies are presented testing a model of the cognitive performance deficits shown in depression. The model proposes that such deficits occur as an interaction of expectancy and focus of attention variables, that is, in the presence of both low expectancy of success and high self-focus. Study 1 was a pilot study which documented that depressed undergraduates evidence poorer anagram performance, greater self-focus, and lower pretask expectancies than do nondepressed subjects. Study 2 showed that nondepressed undergraduates evidence performance deficits only when both expectancy is lowered and self-focus is increased. Study 3 suggested that depressed undergraduates' performance deficits are overcome either by lowering self-focus or by raising expectancy. Discussed are discrepancies between self-report and performance data, the relevance of these studies to the test anxiety literature, the need to integrate literature concerning the effects of depression, anxiety, and self-esteem on performance, and how the interactive roles of positive expectancy and focus of attention may be related to effective coping in a variety of situations. 相似文献
984.
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
985.
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
986.
This study compared central nervous system organizational processes underlying balance in children of three age groups: 15-31 months, 4-6 years, and 7-10 years, using a movable platform capable of antero-posterior (A-P) displacements or dorsi-plantar flexing rotations of the ankle joint. A servo system capable of linking platform rotations to A-P sway angle allowed disruption of ankle joint inputs, to test the effects of incongruent sensory inputs on response patterns. Surface electromyography was used to quantify latency and response patterns. Surface electromyography was used to quantify latency and amplitude of the gastrocnemius, hamstrings, tibialis anterior, and quadriceps muscle responses. Cinematography provided biomechanical analysis of the sway motion. Results demonstrated that while directionally specific response synergies are present in children under the age of six, structured organization of the synergies is not yet fully developed since variability in timing and amplitude relationships between proximal and distal muscles is high. Transition from immature to mature response patterns was not linear but stage-like with greatest variability in the 4- to 6- year-old children. Results from balance tests under altered sensory conditions (eyes closed and/or ankle joint inputs altered) suggested that: (a) with development a shift in controlling inputs to posture from visual dependence to more adult-like dependence on a combination of ankle joint and visual inputs occurred in the 4- to 6-year-old, and reached adult form in the 7- to 10-year-old age group. It is proposed that the age 4-6 is a transition period in the development of posture control. At this time the nervous system (a) uses visual-vestibular inputs to fine tune ankle-joint proprioception in preparation for its increased importance in posture control and (b) fine tunes the structural organization of the postural synergies themselves. 相似文献
987.
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
988.
Recent reaction time analysis of motor programming has utilized a precue stimulus that provides advance information about some or all of the attributes for the upcoming motor response. This kind of precue typically confounds the number of remaining stimuli with the motoric processes under investigation (Zelaznik, 1978). In Experiments 1 and 2 the precuing of hand, digit, and duration of a key press response was manipulated. A new precuing procedure was utilized that does not confound the number of stimuli with the motoric processes under investigation. The findings of Experiments 1 and 2 demonstrate that none of the advance information was helpful in reducing reaction time and as such, suggest that these features of movement are not selected in any particular order. Experiment 3 compared this new method of precuing to the other, traditional method. The results of this experiment suggested that there is parallel processing of the perceptual and motor mental operations in this reaction-time task, since there was an underadditive interaction between the number of stimulus response alternatives and the non-precued movement dimensions. This paper highlights problems inherent in the utilization of precursing methods to understand motor programming processes. It appears that a better understanding about the variables involved in movement control is necessary before examining the order of selection of those variables. 相似文献
989.
Evidence for extending the circumplex model of personality trait language to self-reported moods 总被引:1,自引:0,他引:1
G A Fisher D R Heise G W Bohrnstedt J F Lucke 《Journal of personality and social psychology》1985,49(1):233-242
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
990.
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