Ann. N.Y. Acad. Sci. ISSN 0077-8923 ANNALS OF THE NEW YORK ACADEMY OF SCIENCES Issue: The Year in Cognitive Neuroscience A new perspective on the perceptual selectivity of attention under load Barry Giesbrecht, 1 Jocelyn Sy, 2 Claus Bundesen, 3 and Søren Kyllingsbæk 3 1 Department of Psychological and Brain Sciences and The Institute for Collaborative Biotechnologies, University of California, Santa Barbara, Santa Barbara, California. 2 Department of Psychological Sciences, Vanderbilt University, Nashville, Tennessee. 3 Center for Visual Cognition and Department of Psychology, University of Copenhagen, Copenhagen, Denmark Address for correspondence: Barry Giesbrecht, Ph.D., Department of Psychological and Brain Sciences, University of California, Santa Barbara, Santa Barbara, CA 93106. barry.giesbrecht@psych.ucsb.edu The human attention system helps us cope with a complex environment by supporting the selective processing of information relevant to our current goals. Understanding the perceptual, cognitive, and neural mechanisms that mediate selective attention is a core issue in cognitive neuroscience. One prominent model of selective at- tention, known as load theory, offers an account of how task demands determine when information is selected and an account of the efficiency of the selection process. However, load theory has several critical weaknesses that suggest that it is time for a new perspective. Here we review the strengths and weaknesses of load theory and offer an alternative biologically plausible computational account that is based on the neural theory of visual attention. We argue that this new perspective provides a detailed computational account of how bottom-up and top-down information is integrated to provide efficient attentional selection and allocation of perceptual processing resources. Keywords: selective attention; visual attention; load theory; theory of visual attention; perceptual selectivity; distraction Introduction The day-to-day environment is extremely complex and contains much more information than an indi- vidual can process at once. Coherent and adaptive behavior in this environment is therefore dependent on a mechanism that affords the selective process- ing of a subset of the information most pertinent for current behavioral goals, while ignoring distracting information that is largely irrelevant. This mecha- nism is selective attention. And, while the need for a robust selective attention mechanism has not been debated—rather, it often is considered to be self- evident 1–9 —the nature of the selection mechanism has been. For the better part of 40 years (from the late 1950s to the mid-1990s), one of the most promi- nent debates in the literature on selective infor- mation processing was focused on determining the locus in the information processing stream at which attention operated to select information to be acted upon or to be stored in memory a . 3,7,10–14 The year 2014 marks the 20th anniversary of a significant turning point in the locus of selection de- bate. This turning point, based on a theoretical per- spective proposed by Lavie and Tsal, 15 was focused on identifying the conditions under which early (or late) selection could occur, rather than determining whether selective attention is either early or late. Ac- cording to Lavie and Tsal, 15 perceptual load was a a There were, and continue to be, other prominent debates in the attention literature, including debates about the units of selection (space, objects, or features), serial versus parallel information processing models, spotlight versus zoom-lens models, contrast gain or response gain models of the effect of attention on neuronal responses, and the number of attentional foci. doi: 10.1111/nyas.12404 1 Ann. N.Y. Acad. Sci. xxxx (2014) 1–16 C  2014 New York Academy of Sciences.