Abstract
The present study examined how different hand-grasping postures affect the encoding of global configural information in visual working memory (VWM). In three experiments, we conducted an orientation change-detection task while participants grasped handles in two different postures: power or precision grasp. In the change-detection task, participants were briefly presented an array of multiple rotated bars in a memory array and then, after a retention interval, reported whether a cued item in a test array had the same or a different orientation compared to the first array. The availability of global configural information (i.e., the overall shape connecting individual bars) was manipulated by the presence of surrounding circles which impair configural processing, or by the spatial organization of the stimuli (systematic vs. random). The results show that overall change-detection performance benefited from configural encoding. Surprisingly, the magnitude of the configural encoding benefit was larger when participants maintained a precision grasp compared to when they produced a power-grasp. The results are consistent with a bias in favor of parvocellular processing when a precision grasp is prepared. Overall, the findings highlight the functional interaction between manual gestures and feature-specific visual information processing.