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We have recently reported the discovery that the ability to detect a minimum increment to a stimulus depends on the spread of the other stimuli for which this just noticeable difference (JND) is being measured (Namdar, Ganel, & Algom, 2016). In particular, the JND around a standard stimulus was larger when the other standards tested within the same experimental session spread a larger range. In this study we show that this range of standards effect (RSE) is limited to perceptual estimations and does not extend to action. The JND remained invariant when the participants grasped the objects rather than perceptually estimated their size. This difference supports the hypothesis that visual perception, on the one hand, and visually controlled action, on the other hand, are governed by separate rules and mediated by different mechanisms., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Stroop objects are defined by the existence of a logical relationship, congruity or incongruity, between their constituent dimensions. The Stroop effect is the difference in performance between congruent and incongruent stimuli with respect to one of these dimensions. However, the pair of Stroop generating dimensions does not exhaust all dimensions of the object. In this study, we examined performance with respect to a third non-Stroop dimension of an otherwise Stroop object, a dimension that is unrelated to those generating the Stroop effect. We witnessed a reversal of the usual Stroop pattern with respect to the third dimension, the Incongruity Effect. Performance was superior with Stroop-incongruent stimuli despite the fact that congruity was defined with respect to another pair of dimensions. In 8 experiments, we first documented the Incongruity Effect and then tested possible explanations. We conclude that the best account is associated with the notion that Stroop-incongruent stimuli engender negative affect that people strive to swiftly terminate. (PsycINFO Database Record, ((c) 2017 APA, all rights reserved).)

We test the hypothesis that naming an object depicted in a picture and reading aloud an object's name are affected by the object's speed. We contend that the mental representations of everyday objects and situations include their speed, and that the latter influences behavior in instantaneous and systematic ways. An important corollary is that high-speed objects are named faster than low-speed objects, although object speed is irrelevant to the naming task at hand. The results of a series of 7 studies with pictures and words support these predictions., ((c) 2015 APA, all rights reserved).)

Background: Human resolution for object size is typically determined by psychophysical methods that are based on conscious perception. In contrast, grasping of the same objects might be less conscious. It is suggested that grasping is mediated by mechanisms other than those mediating conscious perception. In this study, we compared the visual resolution for object size of the visuomotor and the perceptual system., Methodology/principal Findings: In Experiment 1, participants discriminated the size of pairs of objects once through perceptual judgments and once by grasping movements toward the objects. Notably, the actual size differences were set below the Just Noticeable Difference (JND). We found that grasping trajectories reflected the actual size differences between the objects regardless of the JND. This pattern was observed even in trials in which the perceptual judgments were erroneous. The results of an additional control experiment showed that these findings were not confounded by task demands. Participants were not aware, therefore, that their size discrimination via grasp was veridical., Conclusions/significance: We conclude that human resolution is not fully tapped by perceptually determined thresholds. Grasping likely exhibits greater resolving power than people usually realize.

A cornerstone of contemporary research in numerical cognition is the surprising link found between numbers and space. In particular, people react faster and more accurately to small numbers with a left-hand key and to large numbers with a right-hand key. Because this contingency is found in a variety of tasks, it has been taken to support the automatic activation of magnitude as well as the notion of a mental number line arranged from left to right. The present study challenges the presence of a link between left-right location, on the one hand, and small-large number, on the other hand. We show that a link exists between space and relative magnitude, a relationship that might or might not be unique to numbers.

People indicate the physical size or the parity status of small numbers faster by a left-hand key and those of larger numbers by a right-hand key. Because magnitude information is not required for successful performance in these tasks, the presence of a number-space association (the SNARC effect) has been taken to indicate the automatic activation of numerical magnitude in all tasks with numerals. In order to test this account, in a series of five experiments, we derived two consensual markers of automatic activation of irrelevant numerical magnitude, the size congruity effect (for judgments of physical size), and the Garner effect (for judgments of parity). Both markers were found independent of the SNARC effect. Consequently, we question the traditional explanation of the SNARC effect and offer an alternative account in terms of a highly overlearned stimulus-response loop.