Selective Attention Supports Working Memory Maintenance by Modulating Perceptual Processing of Distractors Kartik K. Sreenivasan and Amishi P. Jha Abstract & Selective attention has been shown to bias sensory pro- cessing in favor of relevant stimuli and against irrelevant or distracting stimuli in perceptual tasks. Increasing evidence suggests that selective attention plays an important role during working memory maintenance, possibly by biasing sensory processing in favor of to-be-remembered items. In the current study, we investigated whether selective attention may also support working memory by biasing processing against irrel- evant and potentially distracting information. Event-related potentials (ERPs) were recorded while subjects (n = 22) per- formed a delayed-recognition task for faces and shoes. The delay period was filled with face or shoe distractors. Behavioral performance was impaired when distractors were congruent with the working memory domain (e.g., face distractor during working memory for faces) relative to when distractors were incongruent with the working memory domain (e.g., face dis- tractor during shoe working memory). If attentional biasing against distractor processing is indeed functionally relevant in supporting working memory maintenance, perceptual pro- cessing of distractors is predicted to be attenuated when dis- tractors are more behaviorally intrusive relative to when they are nonintrusive. As such, we predicted that perceptual pro- cessing of distracting faces, as measured by the face-sensitive N170 ERP component, would be reduced in the context of congruent (face) working memory relative to incongruent (shoe) working memory. The N170 elicited by distracting faces demonstrated reduced amplitude during congruent versus in- congruent working memory. These results suggest that per- ceptual processing of distracting faces may be attenuated due to attentional biasing against sensory processing of distractors that are most behaviorally intrusive during working memory maintenance. & INTRODUCTION One of the challenges of everyday life is to select and maintain relevant information in the presence of a sea of irrelevant, distracting, and competing influences. A large body of work has explored the neural mechanisms by which selective attention helps to differentiate relevant from irrelevant information during perception, but less is known about how attention may support the ability to distinguish between relevant and irrelevant information during working memory. Recently, it has been suggested that selective attention may subserve the active mainte- nance of information in working memory via attentional rehearsal of memoranda (for a review, see Awh, Vogel, & Oh, 2006). That is, attentional selection mechanisms, in the context of working memory, may bias prefrontal and posterior perceptual activity in favor of representations of relevant, to-be-remembered stimuli in order to ensure the high fidelity of mnemonic information over delays. Indeed, several studies of spatial working memory have demonstrated increased perceptual activity to probes appearing in memory locations throughout the entire period of working memory maintenance ( Jha, 2002; Awh et al., 1999). The concept of representational biasing via selective attention has its origins in studies of perception that suggest that the magnitude of stimulus-evoked neural activity can be modulated in a gain control fashion as a function of attention (Hillyard, Vogel, & Luck, 1998; Hillyard, Mangun, Woldorff, & Luck, 1995). By the sensory gain control account of attention, stimulus- evoked activity is amplified in attended channels relative to unattended channels. Studies of perception have also suggested that selection mechanisms may play an im- portant role in the processing of irrelevant or distracting information. Lavie and colleagues have proposed that the degree of perceptual load present during the task influences the manner in which selection mechanisms are recruited for distractor processing (for a review, see Lavie, 2005). Under conditions of high perceptual load— when a large amount of perceptual information is pres- ent, or perceptual task demands are high—cognitive control systems, such as working memory, may recruit selective attention to bias perceptual processing against distracting information (Lavie, 2005). Several of these studies used a response-competition paradigm in which University of Pennsylvania D 2007 Massachusetts Institute of Technology Journal of Cognitive Neuroscience 19:1, pp. 32–41