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981.
The law relating the kinematic and figural aspects of drawing movements   总被引:26,自引:0,他引:26  
  相似文献   
982.
Only a few analysts (Deutsch, 1947, 1952; Braat?y, 1954) have systematically tried to investigate how nonverbal behavior may be derived from events and experiences from the preverbal phase of development. Their approaches to the analysis of such behavior differ. Extracts of an analysis are used to illustrate basic technical and theoretical questions with regard to the possibility of making use of nonverbal material to reconstruct preverbal experiences. It is inferred that the analyst's visual observations of the patient's nonverbal behavior may be a cue to significant events and trauma from the preverbal period. Besides, the specific visual imagery of the patient that, in this case, emerged just after the appearance of nonverbal behavior, may be a valuable source of data for analytic reconstruction.  相似文献   
983.
Group learned helplessness is demonstrated in Experiment I. Groups of 2 tried to turn off noise by their joint action. In the solvable group (S), noise offset was contingent on their sequence of button pushing. In the yoked, unsolvable group (U), noise offset was independent of all sequences of button pushes they produced. In a practice group (O). subjects practiced coordinated sequences of button pushes with their partners, but heard no noise. Later, all 3 groups were tested in pairs in a shuttlebox which required coordinated joint responding to turn off noise. The unsolvable group escaped more poorly than the other 2 groups, paralleling helplessness effects with individuals. Experiment 2 and 3 found no transfer from individual helplessness training to group testing and no transfer from group helplessness training to individual testing. We suggest that the same mechanism, the expectation of response ineffectiveness, may mediate both individual and group learned helplessness.  相似文献   
984.
Subjects viewed 3 X 3 grids in which different subsets of the nine squares were designated as "figure," either by physical shading of those squares or by a verbal instruction to imagine those squares as shaded. The time taken by participants to respond "on" or "off" the figure was measured for single or multiple probe dots, which all appeared on or off the figural subset together, and which had already been shown to be equally detectable against shaded or unshaded squares and in all nine locations within the grid. In contrast to the set-size effect generally found in experiments on memory scanning, reaction time did not necessarily increase with the number of squares in the figural subset. Instead, the critical variable, which in previous research may often have adventitiously covaried with set size, was the spatial compactness of the subsets (as indexed by square-root-area over perimeter): Probes of less compact figures required more time to classify correctly. Subjects were evidently more successful in confining their attention to sets of mutually proximal items. Reasons are given for believing that this principle may also apply in the more abstract representational or semantic spaces that determine reaction times and errors in various other cognitive tasks.  相似文献   
985.
Effect of signaling intertrial unconditioned stimuli in autoshaping   总被引:3,自引:0,他引:3  
Context-unconditioned-stimulus (US) associations have been suggested as the mediator of the response decrement that occurs when extra USs are added to the intertrial intervals (ITIs) of an otherwise standard Pavlovian conditioning situation. The present autoshaping experiments were concerned with the effect of signaling those extra USs, since such signaling might be expected to lessen their ability to condition the context. Experiments 1 and 2 showed that signaling the ITI USs did reduce their detrimental effects on responding to the conditioned stimulus (CS). To determine whether that reduction was due to an impact of signaling on the target-CS-US association or on performance to the target-CS, Experiment 3 examined responding to differentially trained CSs in a common context, as well as responding to identically trained CSs in differentially trained contexts. Whether the CS was tested in a context of relatively high or low associative strength, more responding occurred to the CS trained with signaled, as compared with unsignaled, ITI USs; further, there was more responding to that CS in the more highly valued context. The pattern of results suggests that contextual value does interact with CS-US learning and may also affect performance to the CS.  相似文献   
986.
The role of marking when reward is delayed   总被引:1,自引:0,他引:1  
Two-choice spatial discrimination by rats is enhanced if a salient stimulus marker occurs immediately after every choice response and again after a delay interval (Lieberman, McIntosh & Thomas, 1979). Three experiments further explore this effect. Experiment 1 found that the second marker is unnecessary. Experiment 2 found that a marker presented before a response is as effective as one presented after. Both effects could be explained in terms of markers focusing attention on subsequent cues. Experiment 3, however, found that markers after choice enhance learning even when no discriminative cues are present following the marker. Markers thus appear to initiate both a backward search through memory and attention to subsequent events; both processes help to identify events that might be related to the unexpected marking stimulus.  相似文献   
987.
The present study examined the role of permissive and nonpermissive cues in mediating the relationship between exposure to erotica and aggression. Male subjects viewed either neutral slides with a silent female or erotic slides with a female who made permissive, nonpermissive, or no comments about the slides. The males rated the slides and subsequently rated the female confederate. Male subjects were then given an opportunity to administer their choice of several intensities of shock to the female in a competitive reaction-time task. Subjects in the permissive cues condition rated the erotic slides as more arousing, saw the female as more reasonable and accepting, and selected more intense shocks for the female than did subjects in the other conditions. One explanation of these results is that permissive cues in the presence of erotica led the male to believe that other normally inappropriate behaviors would be tolerated.  相似文献   
988.
We propose that much of the variance among right-handed subjects in perceptual asymmetries on standard behavioral measures of laterality arises from individual differences in characteristic patterns of asymmetric hemispheric arousal. Dextrals with large right-visual-field (RVF) advantages on a tachistoscopic syllable-identification task (assumed to reflect characteristically higher left-hemisphere than right-hemisphere arousal) outperformed those having weak or no visual-field asymmetries (assumed to reflect characteristically higher right-hemisphere than left-hemisphere arousal). The two groups were equal, however, in asymmetries of error patterns that are thought to indicate linguistic or nonlinguistic encoding strategies. For both groups, relations between visual fields in the ability to discriminate the accuracy of performance followed the pattern of syllable identification itself, suggesting that linguistic and metalinguistic processes are based on the same laterally specialized functions. Subjects with strong RVF advantages had a pessimistic bias for rating performance, and those with weak or no asymmetries had an optimistic bias, particularly for the left visual field (LVF). This is concordant with evidence that the arousal level of the right hemisphere is closely related to affective mood. Finally, consistent with the arousal model, leftward asymmetries on a free-vision face-processing task became larger as RVF advantages on the syllable task diminished and as optimistic biases for the LVF, relative to the RVF, increased.  相似文献   
989.
Hierarchical factor solution was used in the present paper in order to examine if two coding processes, simultaneous and successive, would load on a general 2nd level factor. It was further used to test if the coding processes and a factor representing planful behavior will not share the same general factor, revealing their relative independence as expected from a theoretical model of cognitive functions. Results supported the grouping of the coding tasks within a general factor, as well as the emergence of two general factors, one each for coding and planning. Further correlational evidence supported the relative independence of these two kinds of cognitive processes. These findings were discussed in the context of a general factor of intelligence.  相似文献   
990.
Preprogramming vs. on-line control in simple movement sequences   总被引:1,自引:0,他引:1  
In the present experiment the acceleration traces produced during a repetitive arm extension/flexion movement were measured in addition to the RT required to initiate such a movement. The speed at which this task was completed as well as the number of extension/flexion segments were varied to allow for either preprogramming or on-line control. Evidence from the acceleration traces and the RT data suggested that the movements completed as quickly as possible were preprogrammed; whereas, those completed more slowly were controlled on-line. Furthermore, the topologies of the power spectral density functions from the acceleration traces of each type of movement displayed characteristics typical of these forms of control.  相似文献   
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