Article

Emotion Effects on the N170: A Question of Reference?

Department of Psychology, Humboldt-Universität zu Berlin, Rudower Chaussee 18, 12489, Berlin, Germany, .
Brain Topography (Impact Factor: 3.47). 10/2012; 26(1). DOI: 10.1007/s10548-012-0261-y
Source: PubMed

ABSTRACT

We investigated whether face-specific processes as indicated by the N170 in event-related brain potentials (ERPs) are modulated by emotional significance in facial expressions. Results yielded that emotional modulations over temporo-occipital electrodes typically used to measure the N170 were less pronounced when ERPs were referred to mastoids than when average reference was applied. This offers a potential explanation as to why the literature has so far yielded conflicting evidence regarding effects of emotional facial expressions on the N170. However, spatial distributions of the N170 and emotion effects across the scalp were distinguishable for the same time point, suggesting different neural sources for the N170 and emotion processing. We conclude that the N170 component itself is unaffected by emotional facial expressions, with overlapping activity from the emotion-sensitive early posterior negativity accounting for amplitude modulations over typical N170 electrodes. Our findings are consistent with traditional models of face processing assuming face and emotion encoding to be parallel and independent processes.

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Available from: Annekathrin Schacht, Feb 08, 2014
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    • "During this processing step, structural processing of a face takes place, and the brain distinguishes between faces and other visual objects (Bentin et al., 1996). VPP and N170 very likely reflect the same brain process, and their amplitudes vary depending on which reference is applied to the EEG data (Joyce and Rossion, 2005; Rellecke et al., 2013). Even though these components have been associated with structural face processing, their amplitudes may be modulated by facial expression as well (Hinijosa et al., 2015). "
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    • "However, in another recent study, investigating the N170 and EPN responses to arousing and non-arousing body parts, i.e., insulting versus pointing hand gestures, only EPN but not the N170 response was modulated by the affective arousal of the hand gestures (Flaisch & Schupp, 2013). Thus, previous research using other types of stimuli have provided evidence that the arousal-related EPN activity can overlap with the N170 component (Rellecke et al., 2013), but this is not always the case (Flaisch & Schupp, 2013). Regarding the effects of arousal on body processing, the present data do not allow resolving this issue. "
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    Full-text · Article · Sep 2014 · Biological Psychology
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    • "They suggest that the scalp distribution related to the EPN is sensitive to emotional facial expressions while the parallel distribution associated with the N170 is only sensitive to the structural processing of facial stimuli, and that topographies are largely affected by choice of reference. The EPN is more negative in response to emotional compared to neutral facial expressions and is characterized by a more posterior spatial distribution compared to the N170 ERP (Rellecke et al., 2013). Since studies that measured the N170 used different paradigms and different references, a summary of emotion modulation of the N170 ERP must be tentative. "
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