Incidental encoding of numerosity in visual long-term memory

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.     

Characterizing typographic expertise: Do we process typefaces like faces?

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.     

Visual impressions of generative transmission

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.     

Holistic face perception: Mind the gap!

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.     

The effect of feature discriminability on the intertrial inhibition of focused attention

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.     

Investigating local and global effects of surface colours and contours in amodal completion

ABSTRACT

We studied interpretations of partly occluded shapes. Models that account for amodal completion mostly deal with local and global contour characteristics. In the current study, we were interested in the effects of colour on local and global contour completions. In our stimuli, local contour completions comprised simple linear extensions of the partly occluded contours, whereas global contour completions accounted for global shape regularities. Our stimuli were designed such that the visible surface colour could also be completed in a local or global fashion, being consistent or inconsistent with contour completions. We tested the preferred interpretations of the partly occluded shapes by using a sequential matching task. Participants had to judge whether a test shape could be a previously shown partly occluded shape. We found that interpretations of partly occluded shapes depend on both colour and contour characteristics. Additional time bin analyses revealed that for fast responses colour and contour completions already depend on the visible context of the partly occluded shapes, while for slow responses the congruency between colour and contour completions play a role as well.     

Conditional reasoning in context: A developmental dual processes account

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).     

Job insecurity and well-being: The moderating role of job dependence

Job insecurity has become more relevant during the last decades as more flexibility from the workforce and organizations is demanded in the labour market. It has frequently been suggested that job insecurity is a more severe stressor for those who are more dependent on their job. The present study investigates the association between job insecurity and employee well-being by focusing on how employees’ dependence on the job moderates this relationship. Two types of financial dependence (subjective financial dependence and relative contribution to the household income) were studied, along with an indicator of a more psychological dependence on work in general (work involvement). In addition to this, both quantitative and qualitative job insecurity were included. The proposed relations were tested in a sample of Swedish accountancy firm employees. The results of moderated hierarchical regression analyses showed that subjective financial dependence, household contribution, and work involvement moderated the relation between both job insecurity dimensions and job satisfaction. No moderations were found with mental well-being as an outcome. This implies that the extent to which someone depends on their job is important for how job insecurity relates to job satisfaction.