Abstract
Emerging lines of evidence demonstrate the importance of rewards and penalties in guiding attention. Previous debate on the capture of attention by salient visual stimuli has centred on whether distraction is modulated by goals. But capture is ecologically advantageous precisely if the risk of ignoring a new event outweighs the expected utility of the current goal. Such a perspective predicts that rewards and penalties might modulate distraction.
In this study we used a variant of an oculomotor capture paradigm (Theeuwes et al., 1998) to index bottom-up attentional allocation. In such tasks, participants must look towards a non-salient target item, but gaze is often involuntarily captured by a neighbouring bright distractor. We rewarded subjects for each saccade to the correct target, according to their reaction time, while saccades to the salient distractor incurred a fixed penalty.
First, we explicitly manipulated the magnitude of reward and penalty across blocks. Oculomotor capture was significantly reduced by expectation of value. Penalties did this at the expense of slowing down responses, whereas modest rewards simultaneously hastened responses and reduced capture.
Next, we examined the effects of reward history by systematically manipulating the location of the valued and penalised items on the previous trial. The key new finding was that oculomotor capture was specifically exaggerated when a reward was previously missed at the current distractor location. This could not be explained simply on the basis of speeded reaction times, inhibition of return, or motor perseveration.
Our findings argue that attentional capture is reward sensitive, and that recently-missed rewards exert a dynamic, spatially specific pull on the guidance of bottom-up spatial attention.
Meeting abstract presented at VSS 2012