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981.
One of the central hypotheses of learned helplessness theory is that exposure to noncontingency produces a reduced ability to perceive response-outcome relations (the postulated "cognitive deficit"). To test this hypothesis, subjects were exposed to a typical helplessness induction task and then asked to make judgments of the amount of control their responses exerted over a designated outcome (the onset of a light). Support for the postulated cognitive deficit would be found if subjects who experienced the induction underestimated the relation between their responses and outcomes. The results, however, demonstrated that induction subjects (n = 30) made higher and more accurate judgments of control than subjects in a no-treatment control group (n = 30). This finding clearly fails to support the postulated cognitive deficit and highlights the need for other direct tests of the basic hypotheses of helplessness theory.  相似文献   
982.
The present study attempts to correct design weaknesses in earlier studies which assessed the use of early memories (EMs) in identifying psychopathology in children. A new EM scoring system, the CEMSS, was developed to provide an objective, comprehensive analysis of the reported EMs. Subjects were 64 boys, SES IV and V, 8 through 12 years old from four diagnostic groups--Delinquent, Hyperactive, Somatic Complaints, and Schizoid. Overall, the CEMSS provided an effective means to distinguish the diagnostic groups, p less than or equal to .01. The results suggest that content variables best distinguished the type of presenting psychopathology, whereas an earlier study found that structural EM variables most reliably identified the degree of psychopathology.  相似文献   
983.
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   
984.
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   
985.
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   
986.
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   
987.
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   
988.
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   
989.
The growth of stability: postural control from a development perspective   总被引:5,自引:0,他引:5  
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   
990.
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   
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