Welcome to the Quantum Science podcast.

Each episode we bring you stories about developments in science and mathematics.

I'm Susan Vallett.

Electroconvulsive therapy is highly effective in treating major depressive disorder,

but no one knows why it works.

New research suggests it may restore balance between excitation and inhibition in the brain.

That's next.

It's season three of the joy of why, and I still have a lot of questions. Like, what is this thing we call time? Why does altruism exist? And where is Jan 11? I'm here. Astrophysicist and co-host. Ready for anything. That's right. I'm bringing in the A team. So brace yourselves. Get ready to learn. I'm Janelle Levin. I'm Steve Strogatz.

And this is Quantum Magazine's podcast, The Joy of Why. New episodes drop every other Thursday.

Electroconvulsive therapy has a public relations problem.

The treatment sends electric currents through the brain to induce a brief seizure.

It has barbaric, inhumane connotations.

For example, it was portrayed as a sadistic punishment in the film One Flew Over the Cuckoo's Nest.

But for patients with depression that does not improve with medications,

electroconvulsive therapy, or ECT, can be highly effective.

Studies have found that some 50 to 70% of patients with major depressive disorders

see their symptoms improve after a course of

ECT. In comparison, medications aimed at altering brain chemistry help only 10 to 40% of depression

patients. Still, even after many decades of use, scientists don't know how ECT alters the brain's underlying biology.

Bradley Voytek is a neuroscientist at the University of California, San Diego.

He remembers talking to some psychiatry colleagues about the treatment.

And I asked, as a neuroscientist, well, how is this working?

...