There's an interesting cross-over with Dr. John Gottman's research showing that by "softening the startup" (trying to start conversations on a positive note, such that during the first 3 minutes of a conflict conversation both people have positive emotional affect) then the conversation will almost always remain in that quadrant (both people smiling) around a "positive attractor" (like a gravitational body). See his TEDx talk https://www.youtube.com/watch?v=-uazFBCDvVw

Or, on the flip side, it's why the advice "talk to somebody" never actually works in depression, because anyone who's not a paid therapist won't sustain a conversation with someone with a perpetual negative affect. And it's why defensiveness is killer in job interviews -- because you ruin everybody else's affect. And that's in-affect-ive. Ha.