On becoming a leader: Effects of gender and cultural differences on power distance reduction

The present research focused on power processes in a simulated organizational structure consisting of three hierarchical levels occupied by different numbers of mules and females. Subjects were presented with a chart showing the organizational hierarchy of which they were a member placed at the lowest level, and asked to nominate any person for the leader position vacated by the current incumbent. The results of Experiment I (n = 88 Dutch male and female university students) showed that male subjects strongly overnominated themselves, whereas a majority of the female subjects nominated either self or another female. Of the others that were nominated by both males and females, almost all were occupants of positions immediately below the leader position, indicating the normative influence of a bureaucratic rule of leader succession. Experiment 2 was a replicational study carried out in a different culture (n = lOl Polish male and female university students). Polish subjects adhered to the bureaucratic rule more strongly than their Dutch counterparts, and both females and males nominated mostly males. Results are discussed with reference to gender self-stereotypes and cultural differences.     

Temporal buffering and visual capacity: The time course of object formation underlies capacity limits in visual cognition

Capacity limits are a hallmark of visual cognition. The upper boundary of our ability to individuate and remember objects is well known but—despite its central role in visual information processing—not well understood. Here, we investigated the role of temporal limits in the perceptual processes of forming “object files.” Specifically, we examined the two fundamental mechanisms of object file formation—individuation and identification—by selectively interfering with visual processing by using forward and backward masking with variable stimulus onset asynchronies. While target detection was almost unaffected by these two types of masking, they showed distinct effects on the two different stages of object formation. Forward “integration” masking selectively impaired object individuation, whereas backward “interruption” masking only affected identification and the consolidation of information into visual working memory. We therefore conclude that the inherent temporal dynamics of visual information processing are an essential component in creating the capacity limits in object individuation and visual working memory.     

Brain mechanisms associated with background monitoring of the environment for potentially significant sensory events

Background monitoring is a necessary prerequisite to detect unexpected changes in the environment, while being involved in a primary task. Here, we used fMRI to investigate the neural mechanisms that underlie adaptive goal-directed behavior in a cued task switching paradigm during real response conflict or, more generally, when expectations on the repetitive features of the environment were violated. Unexpected changes in sensory stimulus attributes in the currently unattended stimulus dimension thereby led to activations in a bilateral network comprising inferior lateral frontal, intraparietal, and posterior medial frontal brain regions, independent of whether these attributes elicited a factual response conflict or not. This fronto-parietal network may thus play an important role in adaptive responding to potentially significant events outside the current focus of attention.     

Subitizing reflects visuo-spatial object individuation capacity

Subitizing is the immediate apprehension of the exact number of items in small sets. Despite more than a 100 years of research around this phenomenon, its nature and origin are still unknown. One view posits that it reflects a number estimation process common for small and large sets, which precision decreases as the number of items increases, according to Weber’s law. Another view proposes that it reflects a non-numerical mechanism of visual indexing of multiple objects in parallel that is limited in capacity. In a previous research we have gathered evidence against the Weberian estimation hypothesis. Here we provide first direct evidence for the alternative object indexing hypothesis, and show that subitizing reflects a domain general mechanism shared with other tasks that require multiple object individuation.     

"A moment's monument": the central vision of Italian sculptor Medardo Rosso (1858-1928)

One of the basic limitations on visual perception is that it is impossible, in any given moment, to see the world sharply and full of colors beyond the central area of the visual field. This fact was popularized and brought to the attention of artists in the nineteenth century. To accurately represent the 'impression', or vision of a single glance, an artistic work should contain only a central area in focus surrounded by a progressively greater blur. The work of the Italian sculptor Medardo Rosso (1858-1928) may be the first artistic representation of differences in central and peripheral acuity. Despite using the medium of sculpture, typically three-dimensional, Rosso conceived of his art as two-dimensional because in a given moment it is possible to view a scene from only one viewpoint. The analysis of Rosso's photographs of his own sculptures emphasizes the areas of detail and relative blur, allowing a reconstruction of his point de vue unique--where the observer should stand when viewing that specific sculpture. We argue that the role of central and peripheral vision in subjective perception is critical to understanding the work of Rosso, aptly defined by critics as monument d'un instant.     

Endogenous attention modulates the temporal window of integration

Constructing useful representations of our visual environment requires the ability to selectively pay attention to particular locations at specific moments. Whilst there has been much investigation on the influence of selective attention on spatial discrimination, less is known about its influence on temporal discrimination. In particular, little is known about how endogenous attention influences two fundamental and opposing temporal processes: segregation – the parsing of the visual scene over time into separate features, and integration – the binding together of related elements. In four experiments, we tested how endogenous cueing to a location influences each of these opposing processes. Results demonstrate a strong cueing effect on both segregation and integration. These results are consistent with the hypothesis that endogenous attention can influence both of these opposing processes in a flexible manner. The finding has implications for arbitrating between accounts of the multiple modulatory mechanisms comprising selective attention.