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951.
The visual system can readily extract numerosity information from brief experiences. This numerical perception is characterized by diminishing accuracy as numerosity increases, and impaired discrimination for similar quantities and large magnitudes. Here we assess whether these properties apply more broadly to numerosity in visual long-term memory. In surprise memory tests, we observed: Remarkable accuracy in estimating the number of repetitions of an exemplar image (Experiment 1a), that this accuracy decreased but remained high when estimating over categories (Experiments 1b and 1c), that numerical discrimination from memory exhibited psychophysical distance and size effects (Experiment 2), that these effects may derive from stored representations rather than post hoc approximation (Experiment 3a), and that they can reflect total elapsed experience in addition to discrete counts (Experiment 3b). Similar to how numerosity is readily extracted during visual perception, our results suggest that numerosity is encoded incidentally in visual long-term memory.  相似文献   
952.
Studies of face recognition and discrimination provide a rich source of data and debate on the nature of their processing, in particular through using inverted faces. This study draws parallels between the features of typefaces and faces, as letters share a basic configuration, regardless of typeface, that could be seen as similar to faces. Typeface discrimination is compared using paragraphs of upright letters and inverted letters at three viewing durations. Based on previously reported effects of expertise, the prediction that designers would be less accurate when letters are inverted, whereas nondesigners would have similar performance in both orientations, was confirmed. A proposal is made as to which spatial relations between typeface components constitute holistic and configural processing, posited as the basis for better discrimination of the typefaces of upright letters. Such processing may characterize designers' perceptual abilities, acquired through training.  相似文献   
953.
Peter A. White 《Visual cognition》2013,21(9-10):1168-1204
ABSTRACT

Previous research has shown that stimuli in which a moving object (A) contacts a stationary one (B) and stops, and object B then moves off in the same direction, give rise to a causal impression: object A is perceived as producing the motion of object B. This impression is weakened or does not occur if there is a delay between A contacting B and B moving, or if there is a spatial gap between B and the location at which A stops. It is shown that a strong causal impression can occur despite the presence of both gap and delay if there are cues to generative transmission of causal influence from A to B. The cues investigated were successive colour change of a series of objects filling the gap between A and B. Reported causal impressions were stronger with the colour change stimuli than with stimuli in which the objects were present but did not change colour, and stronger if the colour change proceeded from A to B than if it proceeded in the opposite direction. Reported causal impressions increased in strength as the number of objects involved in the colour change increased, consistent with the hypothesis that the colour change is a cue to a process of transmission, and inconsistent with the hypothesis that it is perceived or inferred as involving a chain of causal relations. Other kinds of changes to object properties—a small upward motion, shrinkage without moving, and disappearance—yielded similar results. It appears that any rapid sequential change in object properties in the direction of causal influence can function to give rise to the visual impression of generative transmission. The possible role of apparent motion is discussed.  相似文献   
954.
The most widely used measurement of holistic face perception, the composite face effect (CFE), is challenged by two apparently contradictory goals: having a defined face part (i.e., the top half), and yet perceiving the face as an integrated unit (i.e., holistically). Here, we investigated the impact of a small gap between top and bottom face halves in the standard composite face paradigm, requiring matching of sequentially presented top face halves. In Experiment 1, the CFE was larger for no-gap than gap stimuli overall, but not for participants who were presented with gap stimuli first, suggesting that the area of the top face half was unknown without a gap. This was confirmed in Experiment 2, in which these two stimulus sets were mixed up: the gap stimuli thus provided information about the area of a top face half and the magnitude of the CFE did not differ between stimulus sets. These observations indicate that the CFE might be artificially inflated in the absence of a stimulus cue that objectively defines a border between the face halves. Finally, in Experiment 3, observers were asked to determine which of two simultaneously presented faces was the composite face. Perceptual judgements for no-gap stimuli approached ceiling; however, with a gap, participants were almost unable to distinguish the composite face from a veridical face. This effect was not only due to low-level segmentation cues at the border of no-gap face halves, because stimulus inversion decreased performance in both conditions. This result indicates that the two halves of different faces may be integrated more naturally with a small gap that eliminates an enhanced contrast border. Collectively, these observations suggest that a small gap between face halves provides an objective definition of the face half to match and is beneficial for valid measurement of the behavioural CFE.  相似文献   
955.
956.
Identifying the shape of a colour oddball is faster when the distractor colour is viewed in the preceding target-absent trial and slower when the target colour is previewed, an intertrial effect known as the distractor previewing effect (DPE). We tested the effect of feature discriminability on the DPE. In Experiment 1, we determined the interitem discriminability of two colour pairs and two shape pairs. In Experiments 2 and 3, we measured DPEs with these set of target–distractor discriminability pairs. Our results showed that when the defining features allow for efficient parallel search, the a priori degree of interitem discriminability did not modulate the DPE. The results suggest the DPE does not arise as a strictly bottom-up modulation of saliency of the search-relevant features but reflects an attentional bias aimed at preventing attention from revisiting recently rejected “search features”. The underlying mechanism of this attentional bias is discussed.  相似文献   
957.
958.
The way individuals interpret “if p then q” conditionals varies with content and context, often resulting in a biconditional reading. Surprisingly, truth table tasks reveal the existence of two different types of biconditional interpretations: equivalence, as for promises and threats, and defective biconditional, as for causal conditionals or indicative conditionals involving binary terms. The aim of this study was to determine how the interpretation of indicative conditionals is affected in children, adolescents, and adults, by restricting their context of enunciation to only one possible alternative for both the antecedent and the consequent. Moreover, we wanted to determine what is the exact nature of the biconditional interpretation induced by these restricted contexts. For this purpose, third, sixth, and ninth graders and adults performed a truth-value task on indicative conditionals presented either in restricted on non-restricted contexts. Restricted contexts had no effect on children who have a conjunctive interpretation of the conditional, but elicited a predominant defective biconditional reading in adolescents and adults. These results corroborate the developmental dual process account of conditional reasoning proposed by Gauffroy and Barrouillet (2009).  相似文献   
959.
评价临床路径管理在慢性阻塞性肺疾病急性加重期(AECOPD)的应用效果。通过采用回顾性调查,比较进入临床路径(路径组)和没有进入临床路径(对照组)两组患者在住院费用、住院时间及治疗效果3项指标上的差别。结果显示实施临床路径患者(路径组)的平均住院费用、平均住院日等指标均有不同程度的下降,而治愈率有所上升。从而得出临床路径在AECOPD病种的应用能够规范医疗行为,提高医疗护理质量的结论。  相似文献   
960.
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