Pascal Vrticka, David Sander, Patrik Vuilleumier

Emotion Regulation (ER) includes different mechanisms aiming at volitionally  modulating emotional responses, including cognitive re-evaluation (re-appraisal;  REAP) or inhibition of emotion expression and behavior (expressive suppression;  ESUP). However, despite the importance of these ER strategies, previous  functional magnetic resonance imaging (fMRI) studies have not sufficiently  disentangled the specific neural impact of REAP versus ESUP on brain responses  to different kinds of emotion-eliciting events. Moreover, although different  effects have been reported for stimulus valence (positive vs.negative), no study  has systematically investigated how ER may change emotional processing as a  function of particular stimulus content variables (i.e., social vs.nonsocial).  Our fMRI study directly compared brain activation to visual scenes during the  use of different ER strategies, relative to a “natural” viewing condition, but  also examined the effects of ER as a function of the social versus nonsocial  content of scenes, in addition to their negativeversus positive valence (by  manipulating these factors orthogonally in a 2 × 2 factorial design). Our data  revealed that several prefrontal cortical areas were differentially recruited  during either REAP or ESUP, independent of the valence and content of images. In  addition, selective
modulations by either REAP or ESUP were found depending  on the negative valence of scenes (medial fusiform gyrus, anterior insula,  dmPFC), and on their nonsocial (middle insula) or social (bilateral amygdala,  mPFC, posterior cingulate) significance. Furthermore, we observed a significant  lateralization in the amygdala for the effect of the two different ER  strategies, with a predominant modulation by REAP on the left side but by ESUP  on the right side. Taken together, these results do not only highlight the  distributed nature of neural changes induced by ER, but also reveal the specific  impact of different strategies (REAP or ESUP), and the specific sites implicated  by different dimensions of emotional information (social or negative).