THE NEURAL BASIS OF FACE PROCESSING IN INFANCY AND ITS RELATIONSHIP TO THE DEVELOPMENT OF EMPATHY

ABSTRACT Faces are a salient part of the visual social environment, providing important signals including emotional expression and direction of eye gaze that inform us about other people's feelings and intentions. In this paper, we review the development and neural bases of infants' perception of emotion and eye gaze from faces. Building from the idea that the same or similar brain network responds when we see another person experiencing an emotion as when we actually experience it ourselves, we go on to speculate how the neural system underlying infants' abilities to perceive social information in the face might provide the brain bases for emerging empathy abilities. We conclude by providing suggestions as to how developmental cognitive neuroscientists can bridge the gap between how infants' perceptions are used to give rise to the semantic meaning of emotions and also the understanding of how the emotions displayed reflect the feelings of others. KEYWORDS: faces, emotion, eye-gaze, event-related potentials, infancy. INTRODUCTION Empathy involves the ability to share and understand other people's emotions and feelings. Faces play an important role in this process, since they provide directly observable information about the emotions other people are experiencing and about the focus of their attention; from this perceptual information we can infer their mental and emotional states as well as possible behaviours and actions. This reciprocal form of non-verbal communication permits successful social interaction and is a skill that infants develop over time. In this paper, we will review the neural bases and development of face processing in infants, with the view that the emergence of the abilities to perceive and understand social information from faces is an important basic component in the development of empathy. We will mainly focus on infants abilities' to perceive emotion and direction of eye gaze from faces, because there is a growing literature in this area and because the ability to correctly perceive this social information from the face provides some initial input for sharing and understanding other people's feelings. We will also discuss the more limited literature on brain bases of the development of infants' abilities to connect this perceptual information to its social meaning. We will conclude by discussing implications of this work for our understanding of how the mental and emotional concept of empathy develops. Empathy, Face Processing and the Social Brain in Adults To set the background for understanding the development of face processing and its links to emerging empathy skills in infants, we will first give a brief overview of what is known about the brain underpinnings of these skills in adults. In adults, a network of interconnected brain regions involving subcortical, frontal cortical and temporal cortical regions has long been implicated in social cognition. In recent years a number of specific brain regions within this broad network have been identified as components of the 'social brain' including the amygdala, orbital frontal cortex, temporopolar cortex, anterior cingulate cortex, superior temporal sulcus and fusiform gyrus (Johnson, 2005a,b; Payne & Bachevalier, 2009). With respect to processing information in faces, a dominant framework proposes that visual information about faces is initially passed along two neural pathways. In the subcortical pathway, information travels from the retina directly to the superior colliculus, then to the pulvinar and on to the amygdala (de Gelder, Frissen, Barton, & Hadjikhani, 2003; Johnson, 2005b). This system is involved in detecting faces and directing visual attention to them. In the core cortical pathway, information travels from the retina via the geniculo-striate pathway, and includes the inferior occipital gyrus (encompassing the lateral occipital area, of which the 'occipital face area' is a subregion), fusiform gyrus (including the 'fusiform face area') and posterior superior temporal sulcus/gyrus. …