Have you ever wondered why different antidepressants have the same effect, even when they change your serotonin levels in various ways? Well, guess what? Our friend Kirsch (2014) questioned the same thing. He suggested that the reason might not be tied to the drugs' chemical workings, but instead, something called the placebo effect.

Imagine this - you're participating in a science fair, and you are told that the gummy bear you are given will make you smarter. You believe it and do exceptionally well on the quiz afterward. That's the placebo effect at play.

Have you ever thought you'd ace a test just because your favorite teacher was invigilating? That's a bit like the enhanced placebo effect Kirsch mentions. In many trials, patients and doctors, like expert detectives, often figure out the conditions of the experiment, which might skew the results due to experimenter bias and demand characteristics.

But there's a dark side to this story - Kirsch suggests that antidepressants could interfere with our brain's natural mood-management system, making us more susceptible to future episodes of depression.

Kirsch and Sapirstein's first meta-analysis in 1998 was like a bombshell in academia. They found that 75% of the effect of antidepressants could be duplicated by the placebo effect, causing an uproar among scholars who claimed their study selection was biased.

But they didn't back down. In 2002, they used the Freedom of Information Act to ask the FDA for all data on antidepressants. Their findings? A whopping 82% of the antidepressant effect could be explained by placebo.