Investigating Facial Behavior Indicators of Suicidal Ideation

Suicide is the deliberate self-inflicted act with the intent to end one’s own life. It reflects both profound personal suffering and societal failure. While certain suicide risk factors are well understood, predicting suicide attempts remains a very challenging problem. In this paper, we investigate non-verbal facial behaviors to discriminate among control, mentally ill, and suicidal patients. For this task, we used a balanced corpus containing interviews of male and female patients with and without suicide ideation and/or mental health disorders from 3 different hospitals. In our experiments, we explored smiling, frowning, eyebrow raising, and head motion behaviors. We investigated both the occurrence of these behaviors and also how they were conducted. We found that facial behavior descriptors such as the percentage of smiles involving the contraction of the orbicularis oculi muscles (Duchenne smiles) had statistically significant differences between the suicidal and nonsuicidal groups. Our experiments also demonstrated that the stage of the interview in which these facial behaviors occur impacts their discriminative power.