How powerful are placebos?
Plus, unfinished business
BRAIN WAVES
The power of belief. We’ve all heard of the placebo effect, but how powerful is it, exactly? A new study wanted to see whether placebos could improve memory, stress, and physical performance in older adults — even when people were aware that they were taking them. Researchers recruited 90 healthy older adults and split them into three groups: no treatment, a deceptive placebo group (told the pill had active ingredients but it didn’t), and an open‑label placebo group (told upfront the pill was fake but might trigger mind‑body benefits). Over three weeks, participants completed questionnaires and took tests measuring short‑term memory, selective attention, and physical performance. The results were surprising: both placebo groups improved, but the people who knew the pill was fake generally improved the most—showing better memory, lower stress, and a greater boost in physical performance. The placebo effect might work even when we’re aware of it.
Unfinished business. Has your brain ever refused to let go of an unfinished task on your to-do list? There’s a name for that. The Zeigarnik effect is the idea that we remember unfinished or interrupted tasks better than completed ones. The psychologist it’s named after, Bluma Zeigarnik, first studied the phenomenon in the 1920s after hearing fellow psychologist Kurt Lewin describe a waiter who remembered unpaid orders perfectly but forgot them once the bill was settled. Zeigarnik ran experiments and published her findings in 1927, showing that incomplete tasks can create mental tension that keeps details about the task more memorable. The effect is related to our need for cognitive closure — the desire to resolve ambiguity and close the loop on something. So when you have unfinished business, your brain fixates on it until it’s complete. It’s the same reason cliffhangers work: an interrupted storyline sticks in your head and draws you back for more.
By design. We tell ourselves that meaning comes from impact, passion, or finding the “one right path.” But these beliefs can leave us feeling stuck — even when our lives look perfectly fine on paper. Listen to learn more.
ON THE HIDDEN BRAIN PODCAST
Waking Up Your Spiritual Brain: Part 2: Last week, we talked with psychologist Lisa Miller about the science of spirituality. Today, we explore what those ideas can look like in everyday life. Miller explains why moments of connection, spiritual practices, and even periods of suffering can sometimes open the door to deeper meaning and growth. And on Your Questions Answered, behavioral scientist Dave Evans returns to respond to your comments on designing a meaningful life.
ON THE MY UNSUNG HERO PODCAST
Solitaire Miles’ Story: When Solitaire was 18, she suffered a stroke. At the hospital, medical staff accused her of being intoxicated. Then her high school principal arrived — a nun named Sister Maura Smith.
Don’t forget to send us the story of your unsung hero! Record a voice memo on your phone and email it to myunsunghero@hiddenbrain.org.
ON YOUTUBE: WHY WE PAY TO SUFFER
Pain is meant to be a warning. A hot stove, a sharp thorn—our brains signal for us to pull back. So why do we sometimes bypass this signal and embrace the things that hurt us? We crave painfully spicy foods, watch terrifying movies, and get on rollercoaster rides that have us screaming for our lives. In this video, we explore the strange relationship between pain and pleasure, and what it reveals about why the hardest things in life are often the most meaningful.
MIND GAMES
Two people have $100 in total. One has $40 more than the other. How much does each have?
LAST WEEK’S PUZZLE
I am a number, but when you add ‘G’ to me, I go away. What number am I?
The answer: Gone
MOMENT OF JOY
Have an idea for Hidden Brain? A story you want to share with us? Send an email to ideas@hiddenbrain.org. Listen to us on Spotify, Apple, Amazon Music or your favorite podcast platform.