By Dr. Ken Broda-Bahm:
It's an unfamiliar word, "entrain," but here's what it means. In the hotel bar where I'm writing this, there are two conversations going on. At a table toward the back, two women are having what looks like a serious conversation. They're leaning in towards each other at identical angles, both dropping their chins in the same way, both speaking in the same quiet tone, and both mirroring facial expressions that show concern, then warmth, then humor. Meanwhile, up at the bar, two men are blowing off some steam. Both sit with their backs to the bar as they gaze around the room. Both have their chests out and shoulders back in the same expansive posture. Both are joking in the same loud voice, and both share the same booming laugh at the same times. When one says something funny, the other one repeats it. In each conversation, the two speakers have synced their own verbal, vocal, and physical communication styles. They've unconsciously shared these behaviors in order to create a joint style that sets the tone for the conversation.
That is what it means for communicators to entrain. The definition in a communication context is to match one's behavior to the other in communication. In my post earlier this week, I wrote about attorneys and judges adapting the same disfluencies ("um") and that being predictive of the judge's likelihood of agreeing with the advocate. That is an example of entrainment, but it goes beyond being simply a tactic of communication. The process is a basic building block of communication, even if it is one that we aren't generally consciously aware of. It is also an important principle of human influence. To reach across the barrier that separates us humans from each other, we use physical and verbal mimicry to send and receive basic messages of credibility, likeability, and common purpose. Litigators and others who persuade through an oral medium should be aware of this principle, so this post aims to provide a simple introduction, as well as a few thoughts on litigation contexts where it applies.