title: Perceiving objects by their function: An EEG study on feature saliency and prehensile affordances.
abstract: We examined the feature saliency and prehensile/motor affordance effects that are visually elicited by a graspable object's most salient features and graspable part, respectively. EEG was recorded from participants who attended a photo of an object, and responded to a left- or right-pointing arrow, which was overlaid on the object 1000 ms after object onset. Analysis of response times demonstrated the presence of a feature saliency effect. Lateralization of posterior alpha suppression showed that attention was initially directed to the object's (most salient) functional end. Pre-movement frontocentral beta suppression and the modulation of the P3 component showed that a response compatible to the functional end was activated before arrow onset. Moreover, lateralization of pre-movement posterior and central alpha suppression indicated a behaviorally masked affordance effect. This suggests that the two effects may occur independently, but without specific attention orienting instructions, the feature saliency effect dominates a potential prehensile affordance effect.
authors.affiliation: Department of Experimental Psychology, Ghent University, Henri Dunantlaan 2, 9000 Ghent, Belgium. Electronic address: dimitrios.kourtis@ugent.be.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Kourtis
authors.affiliation: Department of Experimental Psychology, Ghent University, Henri Dunantlaan 2, 9000 Ghent, Belgium.
authors.forename: Guy
authors.initials: G
authors.lastname: Vingerhoets
mesh_terms: D000328:Adult; D001288:Attention / Q000502:physiology; D004569:Electroencephalography; D005260:Female; D005556:Form Perception / Q000502:physiology; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D008297:Male; D009068:Movement / Q000502:physiology; D009949:Orientation / Q000502:physiology; D010364:Pattern Recognition, Visual / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology*; D011897:Random Allocation; D011930:Reaction Time / Q000502:physiology*; D055815:Young Adult
keywords: Alpha oscillations; Beta oscillations; EEG; Feature saliency effect; Motor affordances; Object perception; P3