Poster C124, Sunday, March 26, 5:00 – 7:00 pm, Pacific Concourse
Perception of size and local/global stimulus features during action preparation: an electrophysiological investigation.
Xavier Job1, Jan de Fockert1, José van Velzen1; 1Goldsmiths, University of London
The classical view that perception and action are functionally distinct processes that serve the selection of stimuli and the programming of actions, respectively, has been challenged in recent years. Behavioural and neuroimaging research has demonstrated that not only can perceptual processing influence motor programming, but the inverse is also possible. Effects suggest that the planning of actions influences early visual processing, such that perceptual features relevant for an upcoming action are facilitated. Here, visual processing of object size and local/global features of compound stimuli during the preparation of power and precision grasping actions is investigated in 16 healthy adults. Participants prepared power or precision grasps before presentation of a large or small task-irrelevant visual probe. Following the probe participants identified a target presented at either the local or global level of a compound stimulus with the prepared grasp. Grasp preparation biased early visual event-related potentials (ERPs) elicited by the probes. Furthermore a behavioural effect of probe size on local/global target detection was modulated by grasp, such that large (vs. small) probes only facilitated global (vs. local) processing during power (vs. precision) grasp preparation. The results extend recent evidence for influences of motor programming on visual processing and provide support for the tight coupling of action and perception.
Topic Area: PERCEPTION & ACTION: Vision