Spontaneous eye movements and trait empathy predict vicarious learning of fear

• Eye-movements and psychophysiology during vicarious fear learning were examined.
• Fixation time at CS + predicted strength of vicarious fear learning.
• Empathic and autistic traits correlated with the strength of vicarious fear. Empathic traits correlated with fixations to CS +.
• Supports a role of eye movements in vicarious fear learning

Learning to predict dangerous outcomes is important to survival. In humans, this kind of learning is often transmitted through the observation of others' emotional responses. We analyzed eye movements during an observational/vicarious fear learning procedure, in which healthy participants (N = 33) watched another individual (‘learning model’) receiving aversive treatment (shocks) paired with a predictive conditioned stimulus (CS +), but not a control stimulus (CS −). Participants' gaze pattern towards the model differentiated as a function of whether the CS was predictive or not of a shock to the model. Consistent with our hypothesis that the face of a conspecific in distress can act as an unconditioned stimulus (US), we found that the total fixation time at a learning model's face increased when the CS + was shown. Furthermore, we found that the total fixation time at the CS + during learning predicted participants' conditioned responses (CRs) at a later test in the absence of the model. We also demonstrated that trait empathy was associated with stronger CRs, and that autistic traits were positively related to autonomic reactions to watching the model receiving the aversive treatment. Our results have implications for both healthy and dysfunctional socio-emotional learning.