Emotion Facilitates Perception and Potentiates the Perceptual Benefits of Attention

Does emotion affect how people see? We investigated the effects of emotion and attention, as well as their conjoint effect, on contrast sensitivity, a dimension of early vision. We manipulated the emotional valence and the attentional distribution of cues preceding a target stimulus and asked observers to judge the orientation of the target as contrast varied. This study provides the first behavioral evidence that (a) emotion enhances contrast sensitivity irrespective of attention and (b) emotion potentiates the effect of attention on contrast sensitivity. Attention allows people to select a subset of information and grant it priority for processing. Attending to information in the environment could play an even more substantial role when that information is emotionally arousing—providing information critical for reacting to changes in the environment. For instance, the sudden appearance of a fearful face in the periphery probably indicates an impending threat or danger, warranting immediate attention. Indeed, there is evidence that emotion facilitates both the speed with which arousing information is processed (Öhman, Flykt, & Esteves, 2001) and the likelihood that it will be processed (Anderson & Phelps, 2001; Vuilleumier & Schwartz, 2001). In a rapid serial visual presentation (RSVP) paradigm, the second of two stimuli presented in rapid succession is often not detected—a phenomenon known as the attentional blink (Raymond, Shapiro, & Arnell, 1992). However, if this second stimulus is emotionally arousing, it is less likely to be missed (Anderson & Phelps, 2001). Although this finding suggests enhanced processing of emotional stimuli, the level at which emotion and attention interact and how they do so is unclear. Could this interaction affect early vision? In an effort to understand the mechanisms responsible for the emotional modulation of attention, researchers have begun to explore the underlying neural circuitry. This exploration has focused on the amygdala, a medial temporal lobe structure known to be important for processing emotional stimuli. Patients with bilateral amygdala damage show no attenuation of the attentional blink with emotional stimuli. This finding indicates that the amygdala is involved in the enhanced perception of emotional events (Anderson & Phelps, 2001). The amygdala responds to the emotional content of an event rapidly (Ledoux, 2002) and prior to awareness (Whalen et al., 1998). It has been suggested that the amygdala facilitates perception by altering sensory cortical processing via feedback connections to visual cortex (Kapp, Supple, & Whalen, 1994; Ledoux, 2002). In studies consistent with this hypothesis, the amygdala and extrastriate cortex have been shown to correlate in their responses to images of fearful faces (Morris et al., 1998), and this modulation is attenuated in patients with amygdala damage (Vuilleumier, Richardson, Armony, Driver, & Dolan, 2004). These studies suggest the amygdala may alter attentional processing in emotional contexts, by Address correspondence to Marisa Carrasco or Elizabeth A. Phelps, New York University, Department of Psychology/CNS, 6 Washington Pl. , 8th Floor, New York, NY 10003, e-mail: marisa.carrasco@nyu.edu or liz.phelps@nyu.edu. NIH Public Access