The processing of emotional facial expressions (EFE) elicits specific evoked brain responses reflecting different stages of the EFE
processing. Here, we focus on the Late Positive Potential (LPP; around 500ms) as a marker of an elaborative processing and
conscious recognition of EFE involving the working memory. But at this latency, during visual exploration, the Event-Related
Potential (ERP) at the stimuli onset and the Eye Fixation-Related Potential (EFRP) at the first fixation onset overlap. Using a
General Linear Model, these potentials can be identified separately. Methods. Twenty-four participants were asked to freely
empathize with the presented EFE (70 natural but standardized EFE -Neutral, Disgust, Surprise, Happiness- before categorizing
them. Results. Around 200ms, early posterior neural activities of the first EFRP were modulated by EFE (Happiness vs Disgust).
During the LPP latency, this modulation provided by cognitive processing from this fixation onset (mean 275ms), strengthened an
activities pattern at left frontal sites -more involved for positive EFE- becoming significant across EFE. In contrast, at right frontal
sites -more involved for negative EFE, another activities pattern, only elicited by the stimuli presentation, was significant across
EFE. Moreover, taken together, these findings are in line with faster and facilitated perceptual processing for negative EFE.
[1]
M. Junghöfer,et al.
The facilitated processing of threatening faces: an ERP analysis.
,
2004,
Emotion.
[2]
Nadine Mandran,et al.
DynEmo: A video database of natural facial expressions of emotions.
,
2013
.
[3]
G. Schwartz,et al.
Differential lateralization for positive versus negative emotion
,
1979,
Neuropsychologia.
[4]
M. Junghöfer,et al.
Attention and emotion: an ERP analysis of facilitated emotional stimulus processing
,
2003,
Neuroreport.
[5]
Guillermo Recio,et al.
Electrophysiological correlates of perceiving and evaluating static and dynamic facial emotional expressions
,
2011,
Brain Research.