Learn More
We tested whether a delay between stimulus presentation and grasping leads to a shift from dorsal to ventral control of the movement, as suggested by the perception-action theory of Milner and Goodale (Milner, A.D., & Goodale, M.A. (1995). The visual brain in action. Oxford: Oxford University Press.). In this theory the dorsal cortical stream has a short(More)
The availability of visual information influences the execution of goal-directed movements. This is very prominent in memory conditions, where a delay is introduced between stimulus presentation and execution of the movement. The corresponding effects could be due to a decay of the visual information or to different processing mechanisms used for movements(More)
When grasping an object, subjects tend to look at the contact positions of the digits (A. M. Brouwer, V. H. Franz, D. Kerzel, & K. R. Gegenfurtner, 2005; R. S. Johansson, G. Westling, A. Bäckström, & J. R. Flanagan, 2001). However, these contact positions are not always visible due to occlusion. Subjects might look at occluded parts to determine the(More)
23 It has been suggested that the kinematics of a reach–to–grasp movement, performed within an 24 action sequence, vary depending on the action goal and the properties of subsequent 25 movement segments (action context effect). The aim of this study was to investigate whether 26 the action context also affects action sequences which consist of several(More)
It has been suggested that the kinematics of a reach-to-grasp movement, performed within an action sequence, vary depending on the action goal and the properties of subsequent movement segments (action context effect). The aim of this study was to investigate whether the action context also affects action sequences that consist of several grasping movements(More)
Researchers proposed that humans may achieve grip adaptation to a new object size by reprogramming and substituting the initially planned motor program. The authors investigated corrective processes in grasping by using a size perturbation paradigm. In 3 experiments, they investigated how grip adjustments are influenced by different perturbation times(More)
It has been observed that grip opening is delayed when participants are asked to execute complex grasping movements, such as passing over an obstacle or a via-position (Haggard and Wing 1998; Alberts et al. 2002). This finding was proposed to indicate a shift toward sequential performance, meaning that complex movements are carried out in independent motor(More)
We investigated the effects of visuo-spatial attention on the kinematics of grasping movements by employing a dual-task paradigm. Participants had to grasp cylindrical objects of different sizes (motor task) while simultaneously identifying a target digit presented at a different spatial location within a rapid serial visual presentation (perceptual task).(More)
Our study examined the effects of performing a pointing movement with the left hand on the kinematics of a simultaneous grasping movement executed with the right hand. We were especially interested in the question of whether both movements can be controlled independently or whether interference effects occur. Since previous studies suggested that eye(More)
In this study we challenge the widely accepted suggestion that visual perception, but not visual control of action, processes object shape in a holistic manner (Ganel and Goodale, 2003, Nature). The finding that perceptual judgments but not visuomotor acts, such as grasping are affected by variations along an irrelevant object dimension(More)