Simple lines and shapes are associated with, and communicate, distinct emotions.

We investigated whether lines and shapes that present face-like features would be associated with emotions. In Experiment 1, participants associated concave, convex, or straight lines with the words happy or sad. Participants found it easiest to associate the concave line with happy and the convex line with sad. In Experiment 2, participants rated (valence, pleasantness, liking, and tension) and categorised (valence and emotion words) two convex and concave lines that were paired with six distinct pairs of eyes. The presence of eyes affected participants' valence ratings and response latencies; more congruent eye-mouth matches produced more consistent ratings and faster reaction times. In Experiment 3, we examined whether dots that resembled eyes would be associated with emotional words. Participants found it easier to match certain sets of dots with specific emotions. These results suggest that facial gestures that are associated with specific emotions can be captured using relatively simple shapes and lines.