Social cues tip the scales in emotional processing of complex pictures.

Perception of a picture is influenced by the social information and emotional value it carries for the viewer. There are still many unanswered questions about how social and emotional processing are related, but it is clear they involve overlapping brain areas and are cognitively interconnected. Yet studies of emotion processing using standardized picture datasets typically leave the social content in the pictures free to vary. In a few studies where the social content has been measured, it correlated with emotional arousal and valence. Here we tested the association between social and emotional content orthogonally, by selecting a similar number of pictures in four categories varying in presence of nonverbal social cues (e.g., gestures, facial expression, body language) and emotional content (neutral, negative). Across two studies, participants (N = 698 in total) provided three ratings for each picture: social relevance (defined as the self-reported use of social cues to understand the picture), valence, and arousal. Despite our best effort to balance the presence of social cues between negative and neutral pictures, ratings of social relevance were strongly associated with ratings of arousal and, to a lesser extent, with valence. These findings likely reflect the intertwined nature of social and emotional processing, which has implications for the neurobiology underlying them, how these systems develop, and how picture databases are used in research.