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961.
Sidman M Wynne CK Maguire RW Barnes T 《Journal of the experimental analysis of behavior》1989,52(3):261-274
Three adult subjects were taught a set of two-choice simultaneous discriminations, with three positive and three negative stimuli; all possible combinations of positive and negative stimuli yielded nine different pairs. The discriminations were repeatedly reversed and rereversed, the former positive stimuli becoming negative and the former negative stimuli becoming positive. With all subjects, a reversal of the contingencies for one pair of stimuli became sufficient to change their responses to all of the other pairs. The reversals had produced functional stimulus classes. Then, all subjects showed conditional discriminations emerging between members of a functional class; given a sample from one class and comparisons from both classes, they selected the comparison that was in the same class as the sample. Next, 2 of the subjects showed that the within-class conditional relations possessed the symmetric and transitive properties of equivalence relations; after having been taught to relate new stimuli to existing class members, the subjects then matched other class members to the new stimuli. Subsequent tests of two-choice discriminations showed that the conditional discriminations had transferred functional class membership to the new stimuli. The 3rd subject, who did not show equivalence relations among functional class members, was also found to have lost the within-class conditional relations after the equivalence tests. 相似文献
962.
The purpose of this study was to determine whether backward walking represented a simple temporal reversal of forward walking and, hence, could be controlled by a reversed cycling of the same group of neurons. Electromyographic (EMG), joint angle, joint moment, and joint muscle power patterns were compared for forward and backward walking, in 6 subjects. The joint angle patterns with the time-base of the backward walking reversed were similar, with the exception of the ankle. The moment patterns were similar except for the knee, whereas the joint muscle powers were almost reversed-polarity images of each other. This suggests that somewhat similar muscle activation patterns could be used to produce both modes of locomotion, but the temporal cycling of muscle contraction would be reversed: Concentric muscle activity in forward walking would become eccentric activity in backward walking, and visa versa. The EMG results generally supported these findings. 相似文献
963.
Newell KM 《Journal of motor behavior》1989,21(1):92-96
One of the significant limitations of the motor control and skill acquisition domain is that the theories, models, and hypotheses are, in most cases, task specific. Many lines of theorizing fail to hold up under even small changes in task constraints, although clearly the field does have some robust phenomena. It is proposed that a broader consideration of the role of task constraints, which is grounded in the methodology of nonlinear dynamics, may help to formulate a more general action theory of coordination and control. 相似文献
964.
Ulrich BD 《Journal of motor behavior》1989,21(4):392-408
Upright locomotion has been, perhaps, the most studied of all human motor behaviors. The acquisition of this motor milestone has been of major interest to developmentalists from the motor as well as the cognitive domains. Until recently, developmentalists have chosen a nonexperimental approach, opting instead to describe the motor behaviors that precede walking, assigning them precursor status, and attributing the sequence solely to maturation of the nervous system. In this paper, I will discuss evidence that suggests that we may better understand this and other aspects of motor development by viewing them from the theoretical perspective of nonlinear and complex dynamical systems. Focus will be on the availability of a coordinated and alternating stepping pattern throughout much of the first year of life. Factors that influence the expression of and variability in this movement pattern will also be discussed. In addition, I will address the need to understand the development of control of pattern formations as well as their coordination, and I will discuss one approach that may provide some insight; that is, to study the modulations and patterns of muscle and other forces underlying limb movements. 相似文献
965.
D L Schacter J F Kihlstrom L C Kihlstrom M B Berren 《Journal of abnormal psychology》1989,98(4):508-514
Previous research on multiple personality disorder (MPD) has been concerned with between-personalities amnesia, and little attention has been paid to within-personality memory function. This study examined the autobiographical memory of a multiple personality patient, I.C., with cueing procedures that have proven useful in previous studies of normal and abnormal memory. Results indicated that I.C. was able to retrieve autobiographical episodes from the recent past, although her performance differed in several respects from that of matched controls. The study also revealed a striking deficit in I.C.'s autobiographical memory for childhood: She was unable to recall a single episode from prior to the age of 10 in response to various retrieval cues, whereas control subjects had no difficulty recalling numerous childhood episodes. This phenomenon of extended childhood amnesia has not been reported previously in studies of MPD. 相似文献
966.
Examined relapse rates in those individuals who have experienced an episode of unipolar depression as a function of the number of previous episodes, gender, age at onset of the episode (less than 40 vs. greater than 40), time since a previous episode, and depression level at time of interview. From of 6,742 participants, 2,046 were interviewed; of these, 1,130 had at least one, 513 reported a second and 173 reported a third episode. The probability for relapse was positively related to number of previous episodes, being female, depression level at time of interview, but not to age at onset (less than 40 vs. greater than 40). Women were also more likely to have more severe episodes. Participants with elevated depression symptoms reported a greater number of previous episodes. Following the first episode, there was a decline in hazard rate for men but not women; following the second episode, there was no change in vulnerability for men; for women, the results were ambiguous. 相似文献
967.
Painting Group Portraits: Studying Life Outcomes for Aggressive and Withdrawn Children 总被引:1,自引:0,他引:1
Aggression and social withdrawal have long been of interest to personality psychologists. The present article presents a longitudinal study of the development of children selected from a community sample who were high on aggression and withdrawal. The selection of outcome variables is discussed, and outcomes during adolescence are described. For both males and females, high aggressiveness was predictive of low intelligence, poor school achievement, and psychiatric problems. For females, high aggressiveness was also predictive of general health problems. High social withdrawal was predictive of poor school achievement. Females who were high on withdrawal also had an elevated rate of abortions. Individuals who were high on both aggression and withdrawal had relatively poor social competence, had general problems with behavior, had low intelligence, and were performing poorly in school. 相似文献
968.
969.
Agreeable fancy or disagreeable truth? Reconciling self-enhancement and self-verification 总被引:6,自引:0,他引:6
Three studies asked why people sometimes seek positive feedback (self-enhance) and sometimes seek subjectively accurate feedback (self-verify). Consistent with self-enhancement theory, people with low self-esteem as well as those with high self-esteem indicated that they preferred feedback pertaining to their positive rather than negative self-views. Consistent with self-verification theory, the very people who sought favorable feedback pertaining to their positive self-conceptions sought unfavorable feedback pertaining to their negative self-views, regardless of their level of global self-esteem. Apparently, although all people prefer to seek feedback regarding their positive self-views, when they seek feedback regarding their negative self-views, they seek unfavorable feedback. Whether people self-enhance or self-verify thus seems to be determined by the positivity of the relevant self-conceptions rather than their level of self-esteem or the type of person they are. 相似文献
970.
Evidence for terror management theory: I. The effects of mortality salience on reactions to those who violate or uphold cultural values 总被引:8,自引:0,他引:8
A Rosenblatt J Greenberg S Solomon T Pyszczynski D Lyon 《Journal of personality and social psychology》1989,57(4):681-690
On the basis of terror management theory, it was hypothesized that when mortality is made salient, Ss would respond especially positively toward those who uphold cultural values and especially negatively toward those who violate cultural values. In Experiment 1, judges recommended especially harsh bonds for a prostitute when mortality was made salient. Experiment 2 replicated this finding with student Ss and demonstrated that it occurs only among Ss with relatively negative attitudes toward prostitution. Experiment 3 demonstrated that mortality salience also leads to larger reward recommendations for a hero who upheld cultural values. Experiments 4 and 5 showed that the mortality salience effect does not result from heightened self-awareness or physiological arousal. Experiment 6 replicated the punishment effect with a different mortality salience manipulation. Implications for the role of fear of death in social behavior are discussed. 相似文献