What defines an affordance?

Distinct visual streams and sub-streams represent perceptual, semantic and motor-related information about manipulable objects. The exact neural correlates and cognitive mechanisms of these objects are still elusive. For instance, what are the diagnostic visual features, processed within the dorsal visual stream, that communicate an object’s afforded action? How is this affordance-related knowledge represented and how are affordances differentiated in the dorsal visual stream? Do such representations exist independently from object-specific semantic representations? Without an in-depth understanding of these issues, the field cannot progress much beyond the dissociation between crudely defined ventral and dorsal processing of objects. This issue is considered critical not only in object perception but also in the fundamental question regarding the role of motor representations in cognition in general. The project herein aims to advance our understanding of this issue by proposing 3 tasks. In these tasks we will combine psychophysics, transcranial direct-current stimulation (tDCS), transcranial magnetic stimulation (TMS) and functional magnetic resonance imaging (fMRI) with multivoxel pattern analysis (MVPA) and support vector machine (SVM) algorithms for classification, and representation similarity analysis (RSA).