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241.
Subjects (N= 28) performing a complex disjunctive concept-formation task on a microcomputer were given the opportunity to seek help following failure to correctly identify concepts. The proportion of those seeking help was significantly greater when the source of help was the computer itself (86%) rather than another person (36%). Consistent with past research, those who did not ask for help gave reasons other than the potential negative social consequences of doing so. Self-report data and a systematic test for the presence of experimenter-induced demand ruled out several possible sources of confounding. The results have implications for designers of time-sharing and networked computer systems.  相似文献   
242.
Social status variables have been shown to influence attributional judgments, but their effects have been demonstrated almost entirely in experimental settings. The influence of such statuses in experimental settings may differ from their influence in natural settings. We examined the influence on attributional judgments of the status characteristics of both subjects and actors in conjunction with variations in the degree of “real world” characteristics of both subjects and social context. These comparisons were drawn through a partial replication of earlier research investigating the effects of a social status variable, victim sex, and a situational variable—type of assault—on attributions about an assault victim. The social status characteristic, victim sex, had less influence on attributions in an adult juror sample than in a student sample and testimony-related characteristics were more influential in the adult juror sample than in the student sample. Thus, the categories of variables that influence attributions appear to depend on the context of judgment and on the breadth of subjects' life experience. These findings are discussed and we conclude with the caution that careful identification of the differences produced by context and subject characteristics is necessary to support generalization of laboratory-based research.  相似文献   
243.
The relative importance of genetic and environmental factors for neuroticism, extraversion, impulsivity, and monotony avoidance were estimated in a sample of 99 monozygotic and 229 dizygotic pairs of twins reared apart (TRA) and a matched sample of 160 monozygotic and 212 dizygotic pairs of twins reared together (TRT). The average age was 58.6 (SD = 13.6); 72% of the twins were 50 or older. Model-fitting analyses verified the importance of genetic factors for all four measures; from 23% to 45% of the total variation was attributable to genetic sources. There was considerable evidence that these factors were operating in a nonadditive manner for extraversion and impulsivity. Shared environment accounted for less than 10% of the variance; some evidence for selective placement was found for neuroticism.  相似文献   
244.
A modification of the procedure originally used by Davidson, Suppes, and Siegel (1956) to measure subjective utility was used to study the influence of positive affect on individuals' perceived value (utility) functions. Results indicated, as expected, that persons in whom positive affect had been induced showed a more negative subjective utility for losses than did controls. This indicates that losses seem worse to people who are feeling happy than to those in a control condition. The subjective utility functions of the two groups did not differ as much, however, when people were considering potential gain. Thus, at least in the situation tested in this study, potential gains did not seem to be more appealing (nor less so) for affect subjects than they did for controls. These findings are discussed in relation to theoretical issues in decision making and work suggesting that positive affect can promote increased sensitivity to losses in situations of potential meaningful loss.  相似文献   
245.
We interviewed spinal-cord-injured, other handicapped, and nonhandicapped subjects to investigate the relation between the perception of autonomic arousal and experienced emotion. The three groups differed significantly on only one measure of affect intensity, with the spinal-cord-injured subjects more often reporting stronger fear in their lives now compared with the past. In addition, spinal-cord-injured subjects often described intense emotional experiences. Spinal-cord-injured subjects who differed in their level of autonomic feedback differed in intensity on several measures. Subjects with greater autonomic feedback tended to report more intense levels of negative emotions. The findings indicate that the perception of autonomic arousal may not be necessary for emotional experience. There were weak trends in our data, however, suggesting that the perception of arousal may enhance the experience of emotional intensity. The subjective well-being reports of the handicapped groups were comparable to those of nonhandicapped subjects, indicating successful coping with their disability.  相似文献   
246.
The recognition of threatening facial stimuli   总被引:1,自引:0,他引:1  
Two studies examined the information that defines a threatening facial display. The first study identified those facial characteristics that distinguish between representations of threatening and nonthreatening facial displays. Masks that presented either threatening or nonthreatening facial displays were obtained from a number of non-Western cultures and scored for the presence of those facial features that discriminated between such displays in the drawings of two American samples. Threatening masks contained a significantly higher number of these characteristics across all cultures examined. The second study determined whether the information provided by the facial display might be more primary nonrepresentational visual patterns than facial features with obvious denotative meaning (e.g., diagonal lines rather than downturned eyebrows). The subjective response to sets of diagonal, angular, and curvilinear visual stimuli revealed that the nonrepresentational features of angularity and diagonality in the visual stimulus appeared to have the ability to evoke the subjective responses that convey the meaning of threat.  相似文献   
247.
248.
The nature of visually guided locomotion was examined in an experiment where subjects had to walk to targets under various conditions. Target distance was manipulated so that subjects had to (a) lengthen their paces in order to hit the target; (b) shorten their paces; (c) make no adjustments to their standard pace length at all. They did this under four visual conditions: (a) normal vision; (b) with vision restricted to a "snapshot" each time the foot that was to be placed on the target was on the ground; (c) with a snapshot each time the foot to be placed was in the swing phase; and (d) no vision after departure fro the target. The results show that the subjects succeed in reaching the target in most cases. However, the smoothness and fluidity of their movements vary significantly between conditions. Under normal vision or where visual snapshots are delivered when the pointing foot is on the ground, locomotion is smoothly regulated as the subjects approach the target. where snapshots are delivered when the pointing foot is in the swing phase, regulation becomes clumsy and ill coordinated. Where no vision is available at all during the approach, adjustments are made, but these are least coordinated of all. The results show that well-coordinated visual regulation does not require continuous visual guidance but depends on intermittent information being available at the appropriate times in the action sequence. Such timing is often more important than the total amount of information that is available for guidance.  相似文献   
249.
Developmental sequence, relative timing, center of gravity, and phase-plane analyses were used to study a minimum of 15 years of longitudinal, filmed data on the development of hopping in 7 children. The developmental sequences revealed common, qualitative changes in the movement of the children, although each child progressed through the changes at his/her own rate. The timing analyses showed that, in the advanced hop, the tightest limb relationships were found within the hopping leg, then between contralateral limbs of the same girdle, and then between legs and arms. Relative-timing calculations revealed (a) intralimb, timing invariances that were present in first attempts to perform the skill at age 3 and remained for 15 years across all developmental levels; (b) emergent, interlimb timings that gradually became invariant; and (c) intra- and interlimb timing showing gradual development over the 15 years. One invariant, the time between landing and deepest knee flexion, is also invariant in the walk and the run (Shapiro, Zernicke, Gregor, & Diestel, 1981). Phase plane analyses indicated that the timing of peak and zero velocities may be the coordinative constant accounting for a relative timing invariance between the two legs. Position of the body's center of gravity may explain the invariant relative time between landing and deepest knee flexion, or the explanation could lie in the "equation of constraint" regulating joint equilibrium points. The data suggest that modeling the developing hop as the evolving interaction of four vibratory systems would be promising.  相似文献   
250.
We conducted three studies that tested a "change-of-standard" perspective on the relations among context, judgment, and recall. Each study consisted of two or three sessions held a few days apart. All subjects read about the sentencing decisions of one or two target trial judges and of six nontarget trial judges who consistently gave either higher or lower sentences than the target judge(s). Each study varied both the standard that was available when subjects initially judged the sentencing decisions of a target judge and the standard available when subjects subsequently recalled those decisions. To accomplish this, we varied the context of judgment, the timing of judgment, and the overall category norm for trial judges' sentencing decisions that was available at recall. We found that although subjects had been exposed to the same target information and had initially judged it in the same way, their recall of the information was different depending on whether and how a change-of-standard had occurred between judgment and recall. Unique predictions of the change-of-standard perspective were confirmed that could not be accounted for in terms of other types of context effects on judgment and memory.  相似文献   
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