Abstract
It has been demonstrated that humans can learn associations between a stimulus and a response such that they can respond faster when the same response is again required to the same stimulus (the priming effect). Such priming effects can be separated into effects of stimulus-task associations and stimulus-action associations (Waszak, Hommel, Allport 2003; Moutsopoulou and Waszak 2012). Here we wanted to examine whether repetition of the basic features of a visual stimulus, such as colour, is important for priming effects on task and/or action or if repetition of shape is sufficient. The stimuli were images of objects the shape of which was defined by a region in a dynamic random dot stereogram where dots were given a different colour and binocular disparity from the background. This region was slightly shifted between frames to create motion of the entire image without motion of individual dots. The participants’ had to perform one of two tasks, such as judging the size of the object, each with two possible responses. A cue displayed before each image indicated which task to perform and which key to use for each response. Each object was displayed three times: two prime and one probe presentation. Each stimulus feature, the task and the mapping between response and key-press was either switched or repeated between the second prime and the probe. We found an overall reduction in reaction times with repeated presentations (priming effect) and this effect was smaller when the classification or action was switched. However, there was no significant difference associated with switching the stimulus features nor was there an interaction between task or action switch and feature switch. This suggests that priming does not occur at the level of the basic features defining a visual stimulus but at a later level of stimulus processing.
Meeting abstract presented at VSS 2014