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921.
922.
The experiments in which the strengths of pattern and of fusion differing in kind from brightness were used as measures indicated that the visual system could distinguish between illuminance and reflectance. From this result and an observation of gray papers by a microscope, it is assumed that luminance has two aspects, one refers to the macroscopic density of photons and another to the proportion of the reflected microscopic areas to the absorbed microscopic areas so that brightness constancy occurs in relation to each of the patterns of the various sizes from a macroscopic pattern visible to the naked eye to a microscopic pattern not visible. It is also mentioned that the strength of fusion is rare but promising as a measure for analyzing brightness. 相似文献
923.
J T Petersik 《Perception & psychophysics》1991,50(5):465-474
In three experiments, difference thresholds (dLs) and points of subjective equality (PSEs) for three-dimensional (3-D) rotation simulations were examined. In the first experiment, observers compared pairs of simulated spheres that rotated in polar projection and that differed in their structure (points plotted in the volume vs. on the surface), axis of rotation (vertical, y, vs. horizontal, x), and magnitude of rotation (20 degrees-70 degrees). DLs were lowest (7%) when points were on the surface and when at least one sphere rotated around the y-axis and varied with changes in the independent variables. PSEs were closest to objective equality when points were on the surface of both spheres and when both spheres rotated about the x-axis. In the second experiment, subjects provided direct estimates of the rotations of the same spheres. Results suggested a reasonable agreement between PSEs for the indirect-scaling and direct-estimate procedures. The third experiment varied sphere diameter (and therefore mean linear velocity of stimulus elements) and showed that although rotation judgments are biased by mean linear velocity, they are not likely to be made solely on the basis of that information. These and past results suggest a model whereby recovery of structure is conducted by low-level motion-detecting mechanisms, whereas rotation (and other) judgments are based on a higher level representation. 相似文献
924.
T Sanocki 《Perception & psychophysics》1991,50(5):490-497
Recognizing forms may involve a contingency in which later processing is modified, depending on the results of early analyses. This hypothesis can be distinguished from feature models, in which features (including early global features) accumulate over time. In four experiments, shape primes were presented briefly, followed immediately and in the same location by a similarly or differently shaped target, and then a mask. Accuracy was measured with a two-alternative forced-choice discrimination. The primes facilitated discriminations between a similarly shaped target and differently shaped foil, as would be expected. More important is that the primes also facilitated discriminations between similarly shaped targets and similarly shaped foils, even though the primes contained only features common to the alternatives and thus provided no discrimination-relevant information. The facilitation effect was constant over variations in the size of the target set, the type of mask, and the type of baseline condition. This result is consistent with the idea of early-to-late contingencies in processing but was not predicted by feature models. 相似文献
925.
Judgment strategies of 169 undergraduate students on problems to judge the contingency between two binary events were identified by the method of rule-based analysis to clarify whether or not the strategies the subjects used would be affected by the concrete nature of the contingency table. Problems were constructed along two factors: total cell frequency and width of range of objective contingencies. Although the factor of total cell frequency had no effect on subjects' strategies, the number of subjects who changed strategies corresponding with problem instances increased when the objective contingencies were set closer to zero or when problems became more difficult. These results are discussed in the context of previous studies of this issue in the literature. 相似文献
926.
T S Mwamwenda 《Psychological reports》1991,69(1):328-330
It was hypothesized that field-dependent persons would be reasoning at the conventional level, whereas field-independent persons would reason at the post-conventional level. Data from 7 female and 3 male graduate students in Canada supported the first hypothesis (8 field-independent vs 2 field-dependent scorers), but not the second one. 相似文献
927.
Juvenile firesetting: a unique syndrome or an advanced level of antisocial behavior? 总被引:1,自引:0,他引:1
R Forehand M Wierson C L Frame T Kemptom L Armistead 《Behaviour research and therapy》1991,29(2):125-128
The current study examined whether juvenile firesetting represents a unique syndrome or an advanced level of antisocial behavior. Thirty-six incarcerated juvenile delinquents, all of whom met criteria for a diagnosis of Conduct Disorder, served as subjects and were categorized into one of three groups: firesetters, non-firesetters but comparable to firesetters in number of conduct disorder symptoms, and non-firesetters who displayed fewer conduct disorder symptoms than the other two groups. Caregivers completed the Child Behavior Checklist on the youth to provide information about the severity and range of psychopathology. The results indicated that firesetters and non-firesetters who had a comparable number of symptoms did not differ from one another on the CBCL subscales of adolescent psychopathology but both differed from the group with fewer symptoms. These results suggest that firesetting does represent an advanced level of antisocial behavior, but that firesetting is not a unique syndrome, at least not in terms of caretakers' perceptions of the youths' problematic behavior. Implications for treatment of firesetters are presented. 相似文献
928.
The aim of this study was to investigate the possible relations between specific personality variables and the effect of subliminal stimulation on choice behavior. It was hypothesized that subjects with low anxiety, less neuroticism, and external locus of control and the trait of extraversion would be more susceptible to subliminal stimulation. 38 undergraduate students were exposed to subliminal messages urging them to choose symbols instead of numbers or letters. Analysis showed that subliminal stimulation did not generate a preference for symbols over numbers or letters. No support was observed for the hypothesis of an association between susceptibility and personality variables. These results may be explained in terms of symbol choice being a neutral message that did not relate to the subjects' needs and motivation. 相似文献
929.
Differential-approach tendencies of individual incubator-hatched chickens and Japanese quail were assayed using one exemplar of each of the species maternal calls in a simultaneous-choice paradigm. Within 24 hr after hatching, the birds received several short periods of exposure to rotating mounts of an adult female chicken and quail, which emitted the species-appropriate call. All birds were then tested with calls alone over the following 2 to 4 days. The test stimuli were played from speakers located behind pressure-sensitive panels so that approach behavior was recorded when a bird pushed against one of the panels. Both the chickens and the quail, as groups, spent significantly more time attempting to approach the exemplar of their own species maternal call, although there was considerable variation in the magnitude of the approach difference among individuals within each species. Sources of variation in preference scores are analyzed, and a simulation is used to interpret individual differences in response scores. This type of preference test is useful for a number of applications, notably for studying the behavior of quail-chick nervous system chimeras. 相似文献
930.
Ss were trained on the law of large numbers in a given domain through the use of example problems. They were then tested either on that domain or on another domain either immediately or after a 2-week delay. Strong domain independence was found when testing was immediate. This transfer of training was not due simply to Ss' ability to draw direct analogies between problems in the trained domain and in the untrained domain. After the 2-week delay, it was found that (a) there was no decline in performance in the trained domain and (b) although there was a significant decline in performance in the untrained domain, performance was still better than for control Ss. Memory measures suggest that the retention of training effects is due to memory for the rule system rather than to memory for the specific details of the example problems, contrary to what would be expected if Ss were using direct analogies to solve the test problems. 相似文献