Early influence of affective context on emotion perception: EPN or Early-N400?

Abstract

Recent studies have shown that affective context influences the processing of emotional images at early stages. Yet, the mechanisms underlying the emotional modulation of early sensory processing have not been totally elucidated. Emotional information plays a relevant role modulating several cognitive processes such as perception (Vuilleumier et al., 2004), attention (Vuilleumier, 2005; Yiend, 2010), memory (Kensinger, 2009), semantic integration (Egidi and Nusbaum, 2012), and social cognition (Forgas, 2001; Gross, 2002; Batty and Taylor, 2003). Emotions are supported by dynamic interactions among neuronal networks, linking emotional processing centers (e.g., amygdala, hippocampus), with noticeable connections to early sensory areas (Pessoa, 2008). These influences have been characterized through the modulation of two different Event Related Potentials (ERPs): (a) the Early Posterior Negativity (EPN) (Hietanen and Astikainen, 2013), related with the amount of attentional resources to facilitate the early selective perceptual processing of emotional stimuli (Junghöfer et al., 2001; Schupp et al., 2003); and (b) the early-N400 (Diéguez-Risco et al., 2015; Dozolme et al., 2015), classically related with the contextual influence on the effort to integrate incoming information in semantic processing (Kutas and Federmeier, 2011). Here, we discuss that the variations in latency, topography, and amplitude reported in these previous studies as an early-N400 component, fit better with those modulations observed in the EPN component, suggesting that affective context influences the allocation of attentional resources for emotional stimuli processing at early stages of perception.