If you listen closely to giggles, guffaws, and polite chuckles, you can discern a huge amount of information about people and their relationships with each other. This week, we talk with neuroscientist Sophie Scott about the many shades of laughter, from cackles of delight among close friends to the "canned" mirth of TV laugh tracks.

The United States spends trillions of dollars on healthcare every year, but our outcomes are worse than those of other countries that spend less money. Why? Physician and healthcare executive Vivian Lee explains the psychological and economic incentives embedded in the American model of medicine, and makes the case for a different way forward.

Unpredictable things happen to us all the time. As part of our annual You 2.0 series on personal growth and reinvention, we revisit two of our favorite stories of loss and the change it brings.

Some challenges feel insurmountable. But psychologist Emily Balcetis says the solutions are often right in front of our eyes. This week, as part of our annual series on personal growth and reinvention, Emily explains how we can harness our sight to affect our behavior.

Sometimes, life can feel like being stuck on a treadmill. No matter how hard you try to get happier, you end up back where you started. What's going on here? We kick off our annual You 2.0 summer series with happiness researcher Elizabeth Dunn, who explains how to fight the treadmill feeling.

Not long after his sixteenth birthday, Fred Clay was arrested for the murder of a cab driver in Boston. Eventually, Fred was found guilty — but only after police and prosecutors used questionable psychological techniques to single him out as the killer. This week on Hidden Brain, we go back four decades to uncover the harm that arises when flawed ideas from psychology are used to determine that a teenager should spend the rest of his life behind bars.

"We hold these truths to be self-evident, that all men are created equal." These words, penned by Thomas Jefferson more than 240 years ago, continue to inspire many Americans. And yet they were written by a man who owned hundreds of slaves, and fathered six children by an enslaved woman. As we mark Independence Day this week, we return to a 2018 episode with Pulitzer Prize-winning historian Annette Gordon-Reed. We explore the contradictions in Jefferson's life — and how those contradictions might resonate in our own lives.

This week on Hidden Brain, research about prejudices so deeply buried, we often doubt their existence. We'll begin with police shootings of unarmed Black men. We also look at how biases affect judges.

Recessions typically damage workers' long-term earnings. NPR's Hidden Brain podcast explains how a study found that students graduating from high school during a recession may be an exception.

If we do a favor for someone we know, we think we've done a good deed. What we don't tend to ask is: Who have we harmed by treating this person with more kindness than we show toward others? This week, in the second of our two-part series on moral decision-making, we consider how actions that come from a place of love can lead to a more unjust world.