Abstract
Abstract Recent developments in technology have provided researchers with the opportunity to explore the interactions between motor and perceptual systems in the brain. A series of experiments have demonstrated effects of action affordances on object perception. Their combined results seem to imply pre-attentive effects on object perception independent of the person’s intention to act on an object (Riddoch, Humphreys, Edwards, Baker & Wilson, 2002; Tipper, Paul & Hayes, 2006; Symes, Ellis & Tucker, 2007). Our experiments took advantage of the phenomenon of object prioritization during unexpected onsets or feature changes of objects, while our participants were viewing real world scenes (Brockmole & Henderson, 2005a). Eye-tracking data were recorded to measure at which point action affordance manipulations would have an effect. By comparing action affordance interference during object onsets against interference during object orientation changes we could differentiate between pre-attentive and post-selection mechanisms. Our results indicate that although there is no evidence of pre-attentive modulation of object prioritization, action affordances do have an effect in post-selection mechanisms, with functionally inconsistent objects attracting attention faster than functionally consistent objects. Also, action affordances affected the encoding of an object in the scene representation during memory guided prioritization, but not during oculomotor capture. Our results therefore support the existence of two separate mechanisms for object prioritization (Brockmole & Henderson, 2005a, 2005b). This finding, in conjunction with our previous research, is consistent with recent evidence that such action affordance influences on visual perception might be based on implicit motion (Riddoch, Bodley Scott & Humphreys, 2010). Moreover, our analyses indicate that the advantage of functionally inconsistent objects to attract attention earlier than functionally consistent ones can be accounted for by the modulation of the viewing time spent on an object violating familiar schemata.
Meeting abstract presented at VSS 2012