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61.
Two studies examined the consequences of turnover, by investigating factors affecting the job satisfaction of people who remain (i. e., stayers) in response to a coworker (i. e., leaver) who departed for a better job. Consistent with Tesser and Campbell's (1983) self-esteem maintenance model, three factors were found to influence the job satisfaction level of stayers: (a) the extent to which they compared their job situation to the leaver's new one, which was negatively related to stayers’ level of satisfaction, (b) the relevance of the leaver to the stayer for social comparison purposes, which was negatively related to the stayers’ level of satisfaction, and (c) the stayers’ trait self-esteem, which was positively related to the stayers’ level of job satisfaction. Theoretical implications, limitations, and future research directions are discussed.  相似文献   
62.
Summary In this study the role of perceptual and motor factors on the motor organization (integrated versus parallel) adopted by musically skilled and unskilled subjects in a polyrhythmic tapping task was investigated. Subjects tapped a 3:2 polyrhythm to match the timing of two isochronous tone trains, one tone train for each hand. Perceptual factors were examined by the manipulation of the frequency difference between the tone trains to produce either an integrated or a streamed percept. Motor factors were examined by comparison of performance on two versions of the 3:2 polyrhythm. In one (simultaneous) version, each cycle of the polyrhythm began with a simultaneous left- and right-hand tap. In the other (shifted) version a 100-ms interval was introduced between the initial left and right taps in each cycle. Examination of the pattern of variances and covariances among intertap intervals suggested that most of the subjects in this study adopted an integrated motor organization that involved interleaving the timing of the two hands. Further analysis revealed that a serial chained model described the pattern of covariances best for the simultaneous pattern, whereas a hierarchical organization described the pattern of covariances for the shifted pattern best. The finding that performance was more accurate with integrated tones than with streamed tones provides some support for a perceptual-motor facilitation hypothesis.  相似文献   
63.
Two experiments are reported, which examined the relative contributions of preload (resting force level), change of force, and the time taken to achieve the force in determining isometric force variability. The findings showed that change of force is the strongest determiner of peak force variability but that preload and time to peak force have smaller though systematic effects. A formula that predicts peak force variability is proposed, with preload as an additive effect to the ratio between the change of force level and the square root of time to peak force. These findings confirm that these three impulse variables are significant in predicting force variability and that the impact of rate of force on peak force variability is nonlinear.  相似文献   
64.
The negative repetition effect (NRE) refers to a poorer perception of the target in noise-same-as-target than in noise-alternative-target displays. Using the parenthesis as target and noise that are either identical or different in orientation, we tested predictions derived from a feature-specific inhibition model (Bjork & Murray, 1977) that explains the NRE as arising from inhibitory interactions among channels handling identical inputs. Contrary to our expectation of evidence for orientation-specific inhibition, a positive repetition effect (PRE) was observed. We also found a PRE for the dimension target sets whose stimuli differ only in orientation and an NRE for the feature target sets whose stimuli differ in the number of elements. Further experiments that systematically varied relationships between alternative targets indicate that these basic findings, termed the stimulus attributes effects, do not arise from pattern masking, perceptual strategies, or response bias.  相似文献   
65.
Summary The role of intention in guiding the behavior of goal-directed systems is a problem that continues to challenge behavioral science. While it is generally agreed that intentional systems must be consistent with the laws of physics, there are many obvious differences between inanimate, physical systems and sentient, intentional systems. This suggests that there must be constraints over and above those of physics that govern goal-directed behavior. In this paper it is suggested that generic properties of self-organizing mechanisms may play a central role in the origin and evolution of intentional constraints. The properties of self-organizing systems are first introduced in the context of simple physical systems and then extended to a complex (biological) system. Whereas behavior of an inanimate physical system is lawfully determined by force fields, behavior of an animate biological system is lawfully specified by information fields. Biological systems are distinguished from simple physical systems in terms of their ubiquitous use of information fields as special (biological and psychological, social, etc.) boundary conditions on classical laws. Unlike classical constraints (boundary conditions), informational constraints can vary with time and state of the system. Because of the nonstationarity of the boundary conditions, the dynamic of the system can follow a complex trajectory that is organized by a set of spatially and temporally distributed equilibrium points or regions. It is suggested that this equilibrium set and the laws that govern its transformation define a minimal requirement for an intentional system. One of the benefits of such an approach is that it suggests a realist account for the origin of semantic predicates, thereby providing a basis for the development of a theory of symbolic dynamics. Therefore, the principles of self-organization provide a comprehensive basis for investigating intentional systems by suggesting how it is that intentions arise, and by providing a lawful basis for intentional behavior that reveals how organisms become and remain lawfully informed in the pursuit of their goals.  相似文献   
66.
比较短尾猴和恒河猴的社会行为模式   总被引:2,自引:0,他引:2  
短尾猴和恒河猴同是猴科猕猴属中两个不同的物种。从习性学的观点看,它们的社会行为模式应是大同而小异的。作者通过对生活在自然栖息地和实验笼内短尾猴所观察到的行为模式,同文献中已公认的恒河猴的行为模式进行比较后发现,这两种动物的社会行为模式虽然在基本上是相似的,但也有明显的差异。有的是行为模式相同,社会含意不尽相同;有的是社会含意相同,模式不同;也有的模式只是短尾猴有,而恒河猴没有。本文把初步观察到的7种不同情况列出。  相似文献   
67.
The cellular expression of S-100β protein is upregulated in Alzheimer's disease and in Down's syndrome, and this protein has been implicated in memory-related processes in laboratory animals. However, the possibility that the α subunit of S-100 is also involved in memory has not yet been examined. In the present study, day-old black Australorp white Leghorn cockerel chicks (Gallus domesticus) received injections of monoclonal antisera to S-100α (1:50) or S-100β (1:500) into each hemisphere immediately after training on a one-trial passive avoidance task. The chicks displayed significantly lower retention levels than control birds that had been injected with antisera to carbonic anhydrase, or with saline (p< .01). S-100α antisera had an amnestic effect when injected between 0 and 20 min after training, with memory deficits occurring from 30 min postlearning, at the point of transition between the A and the B phases of the Gibbs-Ng intermediate memory stage. By contrast, the S-100β antisera needed to be injected either 5 min before or immediately after training and produced amnesia 10 min earlier, at the start of the A phase of the intermediate memory stage. We conclude that the two subunits of the S-100 protein are required at different points in the sequence of events leading to the consolidation of passive avoidance memory.  相似文献   
68.
在左手食指第一节腹侧分别进行1个点、2个点和3个点的定位实验,探讨了多点定位的特点。实验发现,按单个点的定位误差来计算.1个点和3个点的定位误差无显著差异,且二者均显著地低于2个点的定位误差;在2个点的定位中,一个点的定位误差是此2个点的空间距离的函数.定位误差有随距离加大而增加的趋势;在3个点的定位中.同一个点在不同的3点组台中的定位误差无显著差异。结果指示,多点触觉定位除以受刺激的躯体部位框架为参照(基本参照)外,还受到诸刺激点构成的刺激模式(次级参照)的影响。  相似文献   
69.
70.
Attention/likelihood theory has been used to explain the mirror effect in recognition memory. The theory also predicts that any manipulation that affects the recognition of old items will also affect recognition of the new items—more specifically, that all the underlying distributions will move and that they will move symmetrically on the decision axis. In five experiments, we tested this prediction. The first two experiments used encoding tasks during study to change recognition performance for high- and low-frequency words. The results show symmetrical dispersion of the underlying distributions. The final three experiments used repetition to increase recognition performance. Repetition produced a symmetrical pattern of movement that was different from that produced by encoding task. This pattern is, however, also covered by attention/likelihood theory. A further extension of the theory was used to predict response times.  相似文献   
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