Orbitofrontal cortex lesions result in abnormal social judgements to emotional faces.

Facial expressions of emotion display a wealth of important social information that we use to guide our social judgements. The aim of the current study was to investigate whether patients with orbitofrontal cortex (OFC) lesions exhibit an impaired ability to judge the approachability of emotional faces. Furthermore, we also intended to establish whether impaired approachability judgements provided to emotional faces emerged in the presence of preserved explicit facial expression recognition. Using non-parametric statistics, we found that patients with OFC lesions had a particular difficulty using negative facial expressions to guide approachability judgements, compared to healthy controls and patients with frontal lesions sparing the OFC. Importantly, this deficit arose in the absence of an explicit facial expression recognition deficit. In our sample of healthy controls, we also demonstrated that the capacity to recognise facial expressions was not significantly correlated with approachability judgements given to emotional faces. These results demonstrate that the integrity of the OFC is critical for the appropriate assessment of approachability from negatively valenced faces and this ability is functionally dissociable from the capacity to explicitly recognise facial expressions.