My Berkeley dissertation examined laughter in middle-aged and older marriages. Specifically, I was interested in whether different kinds of laughter carried different relational meaning — whether the way a couple laughed together told us something meaningful about the quality of their bond.
It turns out it does. Considerably.
Three Kinds of Laughter
Duchenne laughter is genuine felt amusement — what researchers call the "real" laugh. It involves the orbicularis oculi muscle around the eyes (the muscle that creates crow's feet), which cannot be voluntarily controlled. When this muscle fires, the smile is authentic. When it doesn't, the smile is social — performed rather than felt.
Antiphonal laughter is the shared laugh — the moment when both partners laugh together in spontaneous mutual response to something. It is deeply social and deeply bonding. It is one of the oldest synchrony signals in the mammalian social repertoire.
Voiced laughter refers to the acoustic quality of laughter — whether it is produced on the exhale with phonation (voiced) or without (unvoiced). Voiced laughter tends to be more spontaneous; unvoiced, more controlled.
What the Findings Suggested
The couples in the study who showed the most genuine shared laughter — particularly antiphonal laughter, the mutual kind — tended to show other markers of relational health: higher positive affect, lower physiological reactivity during conflict, greater mutual positive regard during interaction.
When a couple stops laughing together — genuinely, spontaneously, at the same thing at the same moment — something important has left the relationship. It almost always left quietly, and its absence is rarely named as a loss.
In couples showing signs of distress, laughter still occurred — but it was more often unilateral, more often social rather than Duchenne, more often deployed as a tension-reducer rather than as genuine shared amusement. The laughter had become performative rather than connective.
What This Looks Like Clinically
In the therapy room, I notice when couples laugh together. I notice whether it is genuine. These observations often open into territory that is very hard to reach any other way.
"When did you stop laughing together?" is a question I sometimes ask. The answers are always specific. The couples almost always know exactly when it happened. And knowing that — being able to name and locate the moment — is usually the beginning of something.