Neuropsychologia 45 (2007) 75–92 Are you always on my mind? A review of how face perception and attention interact Romina Palermo a,* , Gillian Rhodes b a Macquarie Centre for Cognitive Science (MACCS), Macquarie University, NSW 2109, Sydney, Australia b School of Psychology, University of Western Australia, Perth, WA, 6009, Australia Available online 23 June 2006 Abstract In this review we examine how attention is involved in detecting faces, recognizing facial identity and registering and discriminating between facial expressions of emotion. The first section examines whether these aspects of face perception are “automatic”, in that they are especially rapid, non-conscious, mandatory and capacity-free. The second section discusses whether limited-capacity selective attention mechanisms are preferentially recruited by faces and facial expressions. Evidence from behavioral, neuropsychological, neuroimaging and psychophysiological studies from humans and single-unit recordings from primates is examined and the neural systems involved in processing faces, emotion and attention are highlighted. Avenues for further research are identified. © 2006 Elsevier Ltd. All rights reserved. Keywords: Faces; Identity; Expression; Emotion; Attention; Automatic; Amygdala; Prefrontal cortex; Fear When scanning our complex visual environment we encounter too many items to fully analyze at one time. The brain must therefore evaluate incoming stimuli and devote more cognitive resources to processing important items and events. But what counts as important? Compton (2003) suggests that a primary way to determine importance is to evaluate the emo- tional significance of a stimulus or event. She further argues that stimuli deemed emotionally significant receive enhanced processing and that this occurs via the operation of two atten- tional mechanisms: one that evaluates emotional significance preattentively or “automatically”, and another that gives these significant stimuli priority in the competition for selective atten- tion. Although the emotional value of stimuli may differ between individuals, there are some stimuli – such as snakes, spiders, and human faces – that are emotionally significant to most indi- viduals. Faces are probably the most biologically and socially significant visual stimuli in the human environment, and might therefore be expected to receive enhanced processing as outlined above. In this review we examine whether faces are indeed processed preattentively and whether they preferentially engage mecha- nisms of selective attention. We consider the role of attention in detecting and categorizing faces, in recognizing the identity * Corresponding author. Tel.: +61 2 9850 6711; fax: +61 2 9850 6059. E-mail address: rpalermo@maccs.mq.edu.au (R. Palermo). of individuals and in registering different expressions displayed by faces. In addition, we examine the interactions between neu- ral systems involved in processing faces, emotion and attention. We begin by outlining current neuropsychological models of face perception. Current cognitive and neural models of face perception propose an initial stage of encoding, after which changeable aspects of a face, which are involved in the analysis of expres- sion and eye gaze, are processed relatively independently of its invariant aspects, which are used to determine identity (Bruce & Young, 1986; Haxby, Hoffman, & Gobbini, 2000, 2002). Processing of identity proceeds via the lateral fusiform gyrus (including the fusiform face area, FFA; Kanwisher, McDermott, & Chun, 1997) to anterior temporal regions that are involved in the recollection of biographical information (Haxby et al., 2000, see Fig. 1, yellow shading). Processing of changeable aspects of faces is mediated by the superior temporal sulcus (STS) (Haxby et al., 2000). Perceiving and recognizing emotion from facial expressions involves a complex network of partially independent neural structures (Adolphs, 2002a,b, see Fig. 1, red shading). Cortical pathways, in occipital and temporal neocortex (in particular the FFA and STS), conduct the detailed perceptual analyses necessary to make fine discriminations between facial expressions (Adolphs, 2002a,b, Fig. 1, solid lines). A “dual-route” fear or threat detection system has also been proposed, with a parallel subcortical route to the 0028-3932/$ – see front matter © 2006 Elsevier Ltd. All rights reserved. doi:10.1016/j.neuropsychologia.2006.04.025