The Electrophysiological Markers of Statistically Learned Attentional Enhancement: Evidence for a Saliency Based Mechanism

Abstract

It has been well established that attention can be sharpened through the process of statistical learning, whereby visual search is optimally adapted to the spatial probabilities of a target in visual fields. Specifically, attentional processing becomes more efficient when targets appear at high relatively to low probability locations. Statistically learned attentional enhancement has been shown to differ behaviorally from the more well studied top-down and bottom-up forms of attention; and while the electrophysiological characteristics of top-down and bottom-up attention have been well explored, relatively little work has been done to characterize the electrophysiological correlates of statistically learned attentional enhancement. In the current study, EEG data was collected while participants performed the additional singleton task with an unbalanced target distribution. Encephalographic data was then analyzed for two well-known correlates of attentional processing; alpha lateralization and the N2pc component. Our results showed that statistically learned attentional enhancement is not characterized by alpha lateralization, thereby differentiating it from top-down enhancement. Yet targets at high probability locations did reliably produce larger N2pc amplitudes, a known marker of increased bottom-up capture due to higher target-distractor contrasts. These results support an interpretation of the probability cuing effects where the improved processing of targets at expected locations is mediated by a saliency-based mechanism; boosting the salience of targets appearing at high-probability locations relative to those at low-probability locations.

Pinging the brain to reveal the hidden attentional priority map using encephalography

“…6 for an additional preregistered ERP analysis. While alpha lateralization was not a primary concern for this study as these effects are only robustly seen for horizontally presented stimuli -while the current study also included laterally presented stimuli -for a further analysis of pre-stimulus alpha focusing on horizontal high-probability conditions using this dataset, see 50 ).…”

Statistics Learning of Target Regularities in a Pop-out Search: Behavioral Performance and Neural Mechanisms

“…It was observed that targets appearing in high-probability locations elicited a larger N2pc, a negative ERP component associated with attentional selection (Duncan et al, 2023). In addition, eye-tracking research demonstrated that the probability of first saccade directed to high-probability location was greater than that for the low-probability location (Jiang et al, 2014).…”

Not Simply Two Sides of the Same Coin: Target Enhancement and Distractor Suppression Draw on Independent Neural Mechanisms

“…Chang & Egeth 2019;Cunningham & Egeth, 2016;van Moorselaar & Slagter, 2019;Wöstmann et al, 2019) which further hint at the possibility of separable mechanisms. Studies utilizing physiological approaches have suggested that an ERP component, known as the N2pc, is associated with stimulus enhancement while another ERP component, usually referred to as the PD, is associated with suppression of a distractor, and not with selection of targets (Carlisle & Woodman, 2011;Drisdelle & Eimer, 2021;Duncan et al, 2023;Hilimire et al, 2011;Jannati et al, 2013;McDonald et al, 2013). These physiological measures seem to have somewhat different time courses and scalp topographies (e.g.…”