The role of the Cannabinoid Receptor 1 in adolescents' processing of facial expressions.

The processing of emotional faces is an important prerequisite for adequate social interactions in daily life, and might thus specifically be altered in adolescence, a period marked by significant changes of social emotional processing. Previous research has shown that the Cannabinoid Receptor CB1R is associated with longer gaze duration and increased brain responses in the striatum to happy faces in adults, yet, for adolescents, is it not clear whether an association between CBR1 and face processing exists. In the present study we investigated genetic effects of the two CB1R polymorphisms, rs1049353 and rs806377 on the processing of emotional faces in healthy adolescents. They participated functional magnetic resonance imaging during the Faces Task where participants watched blocks of video clips with angry and neutral facial expressions, and completed the Morphed Faces Task in the laboratory where they watched different facial expressions that switched from anger to fear/sadness or from happiness to fear/sadness and labelled them according to these four emotional expressions. A-allele versus GG-carriers in rs1049353 displayed earlier recognition of facial expressions changing from anger to sadness/fear, but not for expressions changing from happiness to sadness/fear, and higher brain responses to angry, but not to neutral faces in the amygdala and insula. For rs806377 no significant effects emerged. This suggests that rs1049353 is involved in the processing of anger-related negative facial expressions with relation to anger in adolescents. These findings add to our understanding of social emotion-related mechanisms in adolescents. This article is protected by copyright. All rights reserved.
This article is protected by copyright. All rights reserved.