Similar distraction, but differential suppression, for faces and non-face objects: Evidence from behaviour and event-related potentials

In everyday life we constantly experience distractions. Some distractors might be more distracting than others, for example the human face, which has been shown to be very efficient in attracting attention. Here, we employed the irrelevant-distractor paradigm (Forster & Lavie, 2016) to measure behavioural and neural distraction by completely irrelevant faces or non-faces (cars), while participants performed a letter search task that was more (high-load) or less (low-load) demanding. Under low load conditions, faces and cars equally slowed responses on trials with distractors as compared to those without. In high load conditions, neither faces nor cars were distracting. However, event-related potentials revealed larger face-sensitive N170 responses to faces than cars under both load conditions, suggesting that early face-specific processing is present even under high load. A subsequent Pd modulation between 200 and 300 ms contralateral to the distractor position, which has been linked to the active top-down suppression of lateral distractors (Hickey et al., 2009) was stronger for faces compared to cars. Overall, the EEG data indicate early face-specific processes to irrelevant faces irrespective of attentional load, coupled with stronger top-down suppression for faces. Together, these processes might reduce the influence of irrelevant face distractors on behavioural performance.