The power of tears: Observers' brain responses show that tears provide unambiguous signals independent of scene context

Abstract

Only humans produce emotional tears, a fact that has been linked to triggering empathy, social bonding, and providing support in observers. Consequently, either the tears themselves play a crucial role in eliciting such behavior, or, alternatively, the negative context in which they are shed is responsible for these observers' reactions. The present study investigates whether the context in which we see an individual cry influences our perception of tears. We exposed participants (N = 13) to compound stimuli of faces with or without tears, combined with positive, negative, and scrambled backgrounds, while their brain activity was measured using functional magnetic resonance imaging (fMRI). Findings reveal that the lateral occipital gyrus responds to the presence of tears but that the contextual information does not influence this reaction; furthermore, tears appear to facilitate interpreting emotional facial expressions when combined with a positive context. These findings indicate that tears are a robust, unambiguous signal, the perception of which is insensitive to context but can still contribute to the context interpretation. This feature sets tears apart from other facial emotional expressions. This is likely due to their crucial evolutionary role as one of the foremost indicators of discomfort, signaling a need for help and their power to forge a bond between people.

Keywords: Context; Face; Functional magnetic resonance imaging; Lateral occipital gyrus; Tears.

Fig. 1

Examples of stimuli. Compound stimuli consisted of faces with tears or with digitally removed tears and of backgrounds that were either negative, positive, or scrambled. The stimuli included both male and female faces.

Fig. 2

The main effect of tears. Perception of tearful faces resulted in stronger activation of the right middle occipital gyrus compared to faces without tears [F (1,12) = 23.873, p < 0.001].