Zooming in and out from the mental number line: Evidence for a number range effect

The representation of numbers is commonly viewed as an ordered continuum of magnitudes, referred to as the mental number line. Previous work has repeatedly shown that number representations evoked by a given task can be easily altered, yielding an ongoing discussion about the basic properties of the mental number line and how malleable they are. Here we studied whether the resolution of the mental number line is fixed or depends on the relative magnitudes that are being processed. In 2 experiments, participants compared the same number pairs under 2 conditions that differed in terms of the overall range of numbers present. We report a novel number range effect, such that comparisons of the same number pairs were responded to faster under the smaller versus larger number range. This finding is consistent with the idea that the resolution of the mental number line can be adjusted, as if a unit difference is perceived as larger in smaller ranges

Unitization of route knowledge

There are many theories that explain how route knowledge is acquired. We examined here if the sequence of elements that are part of a route can become integrated into a single unit, to the extent that the processing of individual transitions may only be relevant in the context of this entire unit. In Experiments 1 and 2, participants learned a route for ten blocks. Subsequently, at test they were intermittently exposed to the same training route along with a novel route which contained partial overlap with the original training route. Results show that the very same stimulus, appearing in the very same location, requiring the very same response (e.g., left turn), was responded to significantly faster in the context of the original training route than in the novel route. In Experiment 3 we employed a modified paradigm containing landmarks, two matched routes which were both substantially longer and contained a greater degree of overlap than the routes in Experiments 1 and 2. Results were replicated, namely, the same overlapping route segment, common to both routes, was performed significantly slower when appearing in the context of a novel than the original route. Furthermore, the difference between the overlapping segments was similar to the difference observed for the non-overlapping segments, i.e., an old route segment in the context of a novel route was processed as if it were an entirely novel segment. We discuss the results in relation to binding, chunking and transfer effects, as well as potential practical implications

Perfectionism and eating disorder symptoms in female university students: The central role of perfectionistic self-presentation

Purpose: Numerous studies have found perfectionism to show positive relations with eating disorder symptoms, but so far no study has examined whether perfectionistic self-presentation can explain these relations or whether the relations are the same for different eating disorder symptom groups. Methods: A sample of 393 female university students completed self-report measures of perfectionism (self-oriented perfectionism, socially prescribed perfectionism), perfectionistic self-presentation (perfectionistic self-promotion, nondisplay of imperfection, nondisclosure of imperfection), and three eating disorder symptom groups (dieting, bulimia, oral control). In addition, students reported their weight and height so their body mass index (BMI) could be computed. Results: Results of multiple regression analyses controlling for BMI indicated that socially prescribed perfectionism positively predicted all three symptom groups, whereas self-oriented perfectionism positively predicted dieting only. Moreover, perfectionistic self-presentation explained the positive relations that perfectionism showed with dieting and oral control, but not with bulimia. Further analyses indicated that all three aspects of perfectionistic self-presentation positively predicted dieting, whereas only nondisclosure of imperfection positively predicted bulimia and oral control. Overall, perfectionistic self-presentation explained 10.4-23.5% of variance in eating disorder symptoms, whereas perfectionism explained 7.9-12.1%. Conclusions: The findings suggest that perfectionistic self-presentation explains why perfectionistic women show higher levels of eating disorder symptoms, particularly dieting. Thus perfectionistic self-presentation appears to play a central role in the relations of perfectionism and disordered eating and may warrant closer attention in theory, research, and treatment of eating and weight disorders

Implicit response-irrelevant number information triggers the SNARC effect : Evidence using a neural overlap paradigm

Peer reviewedPostprin

Impact of High Mathematics Education on the Number Sense

In adult number processing two mechanisms are commonly used: approximate estimation of quantity and exact calculation. While the former relies on the approximate number sense (ANS) which we share with animals and preverbal infants, the latter has been proposed to rely on an exact number system (ENS) which develops later in life following the acquisition of symbolic number knowledge. The current study investigated the influence of high level math education on the ANS and the ENS. Our results showed that the precision of non-symbolic quantity representation was not significantly altered by high level math education. However, performance in a symbolic number comparison task as well as the ability to map accurately between symbolic and non-symbolic quantities was significantly better the higher mathematics achievement. Our findings suggest that high level math education in adults shows little influence on their ANS, but it seems to be associated with a better anchored ENS and better mapping abilities between ENS and ANS