One puzzling result in training-test paradigms is that effects of reward-associated stimuli on attention are often seen in test but not in training. We focus on one study, where reward-related performance benefits occur in the training and which was discussed contentiously. By using a similar design, we conceptually replicated the results. Moreover, we investigated the underlying mechanisms and processes resulting in these reward-related performance benefits. In two experiments, using search tasks and having participants perform the tasks either with or without (...) individually adjusted time pressure, we disentangled the mechanisms and processes contributing to the reward-related benefits. We found evidence that not only search efficiency is increased with increasing reward, but also that non-search factors contribute to the results. By also investigating response time distributions, we were able to show that reward-related performance effects increased as search time increased in demanding tasks but not in less demanding tasks. Theoretical implications of the results regarding how reward influences attentional processing are discussed. (shrink)

What does it take to be prejudiced against a particular group? And is prejudice always epistemically problematic, or are there epistemically innocent forms of prejudice? In this paper, I argue that certain important forms of prejudice can be wholly constituted by the differential accessibility of certain pieces of information. These accessibility relations constitute a salience structure. A subject is prejudiced against a particular group when their salience structure is unduly organised around that category. This is significant because it reveals that (...) prejudice does not require the presence of any explicit cognitive or emotive attitude, nor need it manifest in behaviour: it can be solely constituted by the organisation of information, where that information may be accurate and well-founded. Nonetheless, by giving an account of ‘undue organisation’ in epistemic terms, I show that this account is compatible with an understanding of prejudice as a negatively valenced epistemic category. (shrink)

Recent evidence has identified the N140cc lateralized component of event-related potentials as a reliable index of the deployment of attention to task-relevant items in touch. However, existing ERP studies have presented the tactile search array to participants' limbs, most often to the hands. Here, we investigated distractor interference effects when the tactile search array was presented to a portion of the body that is less lateralized and peripheral compared to the hands. Participants were asked to localize a tactile target presented (...) among distractors in a circular arrangement to their back. The N140cc was elicited contralateral to the target when the singleton distractor was absent. Its amplitude was reduced when the singleton distractor was present and contralateral to the target, suggesting that attention was directed at least in part to the distractor when the singletons are on opposite sides. However, similar N140cc were observed when the singleton distractor was ipsilateral to the target compared to distractor absent trials. We suggest that when target and singleton distractor are ipsilateral, the exact localization of the target requires the attentional processing of all items on the same side of the array, similar to distractor absent trials. Together, these observations replicate the distractor interference effects previously observed for the hands, suggesting that analogous mechanisms guide attentional selectivity across different body parts. (shrink)

Observers can learn the locations where salient distractors appear frequently to reduce potential interference. The effect that observers appear to learn the spatial distribution of salient but task-irrelevant distractors in the visual environment to reduce the interference caused by such distractors was referred to as ‘statistical learning of distractor locations’. Emerging studies agreed that the observed reduction of distractor interference is largely attributable to better suppression of distractor in frequent locations, however, concerning how this spatial distractor suppression is implemented within (...) the functional architecture of search guidance, and how the learned suppression is processed in the brain to reduce the interference, remains debated and poorly understood. The line of studies of the current dissertation, therefore, explores the cognitive and neural mechanism underlying spatial distractor suppression based on statistical learning. Using psychophysical experiments, the first two studies examined a series of potentially ‘confounding’ factors that might lead to different theoretical conclusions concerning the locus of learned spatial distractor suppression in different studies. We found that irrespective of whether a salient singleton distractor is more likely to occur at multiple locations within a subregion of the display or at a specific location, observers are both likely to adopt the priority-map-based suppression strategy and dimension-based suppression strategy to reduce interference of distractor in the frequent region. Notably, a critical factor determining which strategy is adopted is whether the distractor and non-distractor items swap colors randomly across trials: without color swapping, observers are more likely to acquire a dimension-based suppression; with color swapping, they prefer to develop a priority-map-based suppression in the first beginning, and potentially shift to dimension-based suppression later with the course of learning. The third study employed functional magnetic resonance imaging techniques with the distractor-location learning paradigm with two types of distractors defined in either the same- or different- visual dimension relative to the target. We disclosed that statistical learning of distractor locations involves suppression down to the level of the early visual cortex to reduce distractor interference, potential different neural mechanisms of spatial distractor suppression between distractors defined in a different and the same dimension to the target. With different-dimension distractors, higher-level, dimension-specific filtering mechanisms plays a role to reduce the interference; with same-dimension distractors, interference reduction relies on cutting down lower-level sensory signals. (shrink)