Showing papers by "Frans A. J. Verstraten published in 2009"
TL;DR: Investigation of subjective higher order bodily experiences showed a strong negative correlation between afterimage disruption and the subjective feeling of ownership, suggesting that the brain can resolve multimodal location mismatch by 'disowning' a visible limb, and that the interaction between proprioception and vision is mediated by higher order bodies.
20Â citations
TL;DR: A peculiar condition is reported in which FLE does not occur even when the position of a moving object is estimated at the moment of a transient event, which suggests the construction of a new object representation requires additional time to establish a stable neuronal representation.
Abstract: Recent psychophysical studies have shown that perceived timings of events can be dissociated from their physical temporal relationship. In the flash-lag effect (FLE), a flash presented at the same spatiotemporal position as a continuously moving stimulus is perceived to lag behind the moving stimulus. In the present study, we report a peculiar condition in which FLE does not occur even when the position of a moving object is estimated at the moment of a transient event. In a series of experiments, we compared perceived timings and processing delays for appearance of a new object against feature changes of an existing object. We found that perceived timing of the appearance of a new object is delayed compared to the perception of feature changes updating the properties of an object. Our results suggest the construction of a new object representation requires additional time to establish a stable neuronal representation.
16Â citations
TL;DR: A strong relationship was found between suppression wave speed and induction pulse strength: increasing the contrast or dot density of the induction pulse led to an increase in wave speed.
14Â citations
TL;DR: Increasing the percentage of 2F non-targets, that have to be ignored, was expected to result in increasingly faster search, since it decreases the size of 1F set that has to be searched, but this effect was independent of set size.
5Â citations
TL;DR: It is inferred that overlearned arbitrary visuomotor associations are represented in spatial coordinates, in an effector-independent framework, which raises the possibility that the previously reported involvement of the posterior parietal cortex in overlearner behavior reflects the transition from an arbitrary visUomotor mapping into a spatially based stimulus-location-response mapping.
Abstract: Our movements can be guided directly by spatial information, but also more flexibly through arbitrary rules. We have recently shown that as arbitrary visuomotor mappings became overlearned, they come to rely not only on fronto-striatal circuits, but also on the posterior parietal cortex (PPC). Since this region supports multiple reference frames for hand movements, the question arose whether overlearned visuomotor associations could come to rely on a spatial framework, similar to spatially guided movements. Alternatively, overlearned visuomotor associations could be non-spatial in nature. In this study we investigate the characteristics of the movement representations supporting arbitrary visuomotor mappings by assessing how performance of extensively trained arbitrary visuomotor associations depends on the effector used to provide the response. After extensive training on a set of arbitrary visuomotor associations, subjects were asked to perform the same task in one of two novel settings that varied either the spatial or the motor relationship between visual instructions and finger movements. We found that the change in spatial configuration resulted in a larger amount of interference on the performance of the original mappings than the configuration change in motor coordinates. This result suggests that the visual stimuli became arbitrarily coupled to locations in space and not directly to the finger movements. We infer that overlearned arbitrary visuomotor associations are represented in spatial coordinates, in an effector-independent framework. This result raises the possibility that the previously reported involvement of the posterior parietal cortex in overlearned visuomotor behavior reflects the transition from an arbitrary visuomotor mapping into a spatially based stimulus-location-response mapping.
4Â citations