Narrator: In 1951, a sixteen-year-old boy in England was suffering from a rare and horrific skin condition that covered his body in thick, horny, fish-like scales. The lesions constantly cracked and became infected, leaving him in agonizing pain. Conventional treatments, including skin grafts, had all failed. In a last-ditch effort, he was brought to a physician named Dr. Albert Mason, who decided to try hypnosis. Focusing only on the boy’s left arm, Dr. Mason suggested that the painful growths would clear. Within a week, the scales on that arm loosened and peeled away, revealing healthy, pink skin underneath. The treatment was a success, and eventually, most of the boy’s body was healed.

How can a story, a simple suggestion, physically change the body in such a profound way? This question lies at the heart of Erik Vance’s book, Suggestible You: The Curious Science of How Your Brain Tricks, Persuades, and Sometimes Heals You. Drawing on his own upbringing in a faith-healing religion and his later turn to science, Vance embarks on a journey to uncover the biological mechanisms behind the mysterious and powerful connection between our minds and our bodies.

Narrator: The history of medicine is, in many ways, the history of the placebo effect. For centuries, treatments worked not because of their ingredients, but because people expected them to work. This phenomenon was powerfully documented by anesthesiologist Henry Beecher during World War II. He noticed that soldiers with grievous injuries on the battlefield often refused morphine, reporting little pain. In contrast, civilians back home with similar wounds would beg for painkillers. Beecher realized the difference was context. For a civilian, the injury was the start of a disaster. For a soldier, a wound was a ticket off the front lines and to safety. Their expectation of relief fundamentally changed their experience of pain.

However, this power has a dark side: the nocebo effect. If positive expectations can heal, negative ones can cause harm. One of the earliest documented cases involved a physician in 1886 treating a woman with severe asthma, which she believed was triggered by roses. To test this, the doctor placed an artificial rose in his office. Upon seeing it, the woman immediately suffered a severe asthma attack, despite the flower being fake. Her brain, conditioned by fear and negative expectation, produced a real and debilitating physical reaction. Both placebo and nocebo demonstrate that our brain doesn’t just passively receive reality; it actively creates it based on the stories it believes.

Narrator: For a long time, the placebo effect was dismissed as being "all in your head." But modern neuroscience reveals it is a real, measurable biological event. Our brains have their own internal pharmacy, capable of producing powerful chemicals that can be released simply by the power of suggestion.

Neuroscientist Luana Colloca demonstrated this in a striking experiment. She hooked up volunteers to a device that delivered painful electric shocks, telling them a green light signaled a weak shock and a red light a strong one. In reality, she eventually made both shocks identical in strength. Yet, when participants saw the "safe" green light, they consistently reported feeling less pain. Their brains, expecting a weaker shock, had released natural pain-killing chemicals called endorphins to match that expectation.

This effect is even more dramatic in Parkinson's disease, a condition caused by a lack of the neurotransmitter dopamine. In one study, a patient who arrived in a wheelchair was given what he believed was a cutting-edge new drug. After the treatment, he felt so good that he practically sprinted out of the lab. He was later told the drug was a simple saline placebo. Brain scans confirmed that his belief had triggered a massive release of his brain's own limited supply of dopamine, temporarily reversing his symptoms. Expectation isn't just a feeling; it's a trigger for the brain's own potent chemistry.

Narrator: If placebos are so powerful, why don't they work for everyone? Researchers have long hunted for the "placebo responder," a personality type more prone to suggestion. Recent science suggests the answer may lie in our genes. Harvard researcher Kathryn Hall has focused on a gene called COMT, which is responsible for clearing dopamine from the brain. The gene comes in two main variants. People with one version are "worriers" with higher baseline levels of dopamine, while those with the other are "warriors" who are less anxious but have lower dopamine levels. Hall found that the high-dopamine "worriers" were far more likely to experience a strong placebo effect.

This genetic lottery had profound implications for Mike Pauletich, a man diagnosed with early-onset Parkinson's. He enrolled in a trial for a new gene therapy, which involved drilling holes into his skull. After the procedure, his improvement was miraculous. He regained mobility, his depression lifted, and he started living a full life again. A year and a half later, the company announced the trial had failed; there was no difference between the real therapy and the sham surgery. Mike discovered he had been in the placebo group. He had received nothing but holes in his head. Yet the belief that he had received a cutting-edge treatment was so powerful that it unlocked his brain's ability to heal itself, an effect that lasted long after he learned the truth.

Narrator: The brain's suggestibility extends beyond physical health into the very fabric of our consciousness: our memories. Pioneering psychologist Elizabeth Loftus proved that memory is not a perfect recording of the past, but a reconstructive process that is highly vulnerable to suggestion. In her classic experiments, she showed that by simply changing a single word in a question—like asking how fast cars were going when they "smashed" versus "contacted"—she could implant false memories of broken glass that never existed.

This malleability of memory had tragic real-world consequences during the "Satanic Panic" of the 1980s and 90s. Across the country, therapists using suggestive techniques and hypnosis convinced children and adults they had repressed memories of horrific satanic ritual abuse. People developed vivid, emotionally charged memories of events that never happened, leading to wrongful convictions and shattered lives. These events reveal a startling truth: our brains cannot reliably distinguish between a real memory and one that has been vividly imagined. The story we are told about our past can become the story we remember as truth.

Narrator: The power of expectation shapes our daily lives in countless ways. It dictates how we experience food, exercise, and even addiction. In one study, researcher Alia Crum gave participants the exact same 380-calorie milkshake on two different occasions. The first time, she labeled it the "Indulgence," a 620-calorie decadent treat. The second time, she called it the "Sensi-Shake," a sensible 140-calorie diet drink. When people thought they were drinking the indulgent shake, their bodies produced significantly less ghrelin, the "hunger hormone," leaving them feeling more full and satisfied. Their physical response was dictated not by the shake's contents, but by the story they were told about it.

Crum saw the same effect with hotel chambermaids. She informed one group that their daily work of cleaning rooms was excellent exercise, exceeding the Surgeon General's recommendations. Another group was told nothing. A month later, the maids who reframed their work as exercise had lost weight and showed a drop in blood pressure, despite not changing their behavior. By simply changing their mindset, they changed their physiology. This suggests that the stories we tell ourselves about our health, our habits, and our potential are among the most powerful medicines we possess.

Narrator: The single most important takeaway from Suggestible You is that the human brain is fundamentally an expectation machine. It constantly builds models of the world and then works to make reality fit those models. The stories we internalize—from doctors, marketers, family, or ourselves—are not just entertainment; they are the neurochemical instructions that our bodies follow.

The book challenges us not to become less suggestible, but to become more conscious of the suggestions we accept. It asks us to become critical curators of our own beliefs. The ultimate power lies not in finding the perfect pill or the perfect guru, but in understanding the science of expectation and deliberately choosing the stories that will best serve our health, our goals, and our lives. What story are you telling yourself today?