Poster #: 129
Topic: MMN across modalities
Friday, Sep 11, 2015
Facial expression related vMMN: disentangling the detection of neutral and emotional changes
1UMR 930 INSERM Université François-Rabelais de Tours, France
2Centre Universitaire de Pédopsychiatrie, CHRU de Tours, France
Detecting variations in the environment facilitates our ability to direct our attention toward potentially salient details allowing us to adapt our behavior. In particular, faces rapidly convey important information about other individuals’ emotions and intentions. Recent studies have suggested that visual mismatch negativity (vMMN), a valuable measurement to study automatic change detection, can be elicited when a deviant emotional face is presented among regular neutral faces. However, it is not clear whether this change detection depends on physically salient changes or on the emotional content of the stimulus. Moreover, only few studies on vMMN have controlled for refractoriness effects due to stimulus repetition in an oddball paradigm. In this study we used two deviant expressions, neutral and angry embedded in a repetitive neutral stimuli sequence, while participants were involved in a concurrent task. A “genuine” vMMN was measured for each condition as the subtraction of deviant stimuli presented in an equiprobable paradigm from the same deviant stimuli of the oddball sequence. Thirteen healthy adults took part to the experiment (6 females; mean age=24.4±4.4). Waveform inspection revealed that both neutral and emotional deviant elicited a significant MMN at 310ms over occipital-posterior sites. However statistical analysis revealed a late sustained occipital response for the emotional deviant compared to the neutral in 340-530ms time window. Controlling for low level features changes and refractoriness allows to determine specific neural activity due to emotional salience. Specifically, these results suggest that only late effects are truly associated with emotional change.