"The source of conflict that Tim chose," the researcher is telling them, "is 'You treat me like you're my mom.'" At this, Stacey, an elegant 30-year-old operations manager for a nonprofit in Salt Lake City, stiffens. Tim, her tall, lean 29-year-old photographer boyfriend, smiles awkwardly, abashed. With his slouchy T-shirt, clunky black glasses, and floppy hair, he's a study in nerdy chic. He looks at the floor. "Tim, you should explain what you mean by this particular conflict," the researcher continues, "and then both of you try to resolve it. You'll have four minutes."
"Um—" Tim says, by way of starting.
"What do you mean by that?" Stacey cuts in.
And they're off.
For the past year, Diamond, the associate professor of psychology at the University of Utah in whose laboratory Stacey and Tim now snipe, has been studying how couples argue—specifically, studying the measurable changes that occur in their bodies as they fight. It's a tricky business, though not because she has difficulty eliciting spats. (That part is almost comically easy: Just ask each half of the pair to write down a gripe against the other.) The tougher part is getting the couples to stop squabbling after the researchers have gathered their data.
And the deepest challenge is teasing out the complex interplays between wrath and respiration, heartache and heart rate. Diamond is trying to quantify the role the body and nervous system play in relationships and conflict. In the process, she's uncovering lessons—some practical, some poetic—about how small gestures can lessen the damage of big arguments, and about how even a minor reconsideration of what's really happening between you can tamp down, metaphorically and physiologically, all that furious heat.
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