The Booster Effect: What Does High Sensitivity Give Us?

Based on the book “Sensitivity as a Superpower” by Jenn Granneman and Andre Solo

Is high sensitivity a weakness or an advantage? Journalists Jenn Granneman and Andre Solo set out to answer this question in their book “Sensitivity as a Superpower,” gathering all the scientific knowledge about sensitivity and highly sensitive people (HSP), a term introduced by psychologist Elaine Aron. Contrary to the common belief that high sensitivity is a negative trait that needs to be fixed, the authors argue that it can actually offer significant advantages, making people more adaptable and resilient in challenging life situations.

“Sensitivity as a personality trait has gotten a bad reputation: it’s mistakenly associated with weakness or a flaw that needs to be corrected. If you Google the word ‘sensitive,’ you’ll see what we mean: as of December 2021, related searches included ‘suspicious,’ ‘embarrassed,’ and ‘inadequate.’ Search for ‘I’m too sensitive’ and you’ll find articles like ‘I’m Too Sensitive. How Can I Toughen Up?’ or ‘How to Stop Being So Sensitive.’ Because of this misunderstanding, even sensitive people have become ashamed of this trait. It’s discouraged from childhood (‘Don’t cry!’, ‘Pull yourself together!’) and used against adults (‘You’re exaggerating,’ ‘You’re falling apart’).”

Debunking the myth that sensitivity is a weakness, the authors suggest we view sensitivity as responsiveness—the ability of the body and brain to react more actively to the world. This means that highly sensitive people may feel frustration, pain, and loss more intensely, but they also respond more acutely to danger, beauty, and the feelings of others, and can dive deeper into the essence of situations, experiences, and new ideas.

“Regardless of the terminology, sensitivity means the ability to perceive and respond to external stimuli in a certain way. This ability operates on two levels: 1) perceiving information through the senses; 2) processing information and connecting it to existing knowledge, memories, or ideas. Sensitive people react more strongly on both levels. They naturally take in more information from the environment, process it more deeply and thoroughly, and are more influenced by it.”

Below is an excerpt where the authors discuss three types of sensitivity, how high sensitivity develops, the impact of upbringing, and why prenatal stress can both increase the risk of PTSD and make a person more adaptable and flexible.

The Booster Effect of Sensitivity

Three Types of Sensitivity

Sensitivity isn’t determined by a single gene, so you’ll never find two identical sensitive people. Scientists have identified three main types of sensitivity:

Low Sensory Threshold

You’re highly receptive to information from your senses: smells, sights, sounds, and textures. You’re a “super sensor.” This type of sensitivity determines how attuned you are to your environment and how quickly you become overwhelmed. You likely have a low sensory threshold if the following apply to you:

• You feel tired or drained in crowded places.
• You react strongly even to small amounts of caffeine, alcohol, medication, or other substances.
• Loud noises (like alarms or shouting), scratchy or uncomfortable textures (like a wool sweater), or bright lights bother you.
• You’re sensitive to even slight changes in temperature, such as a room being a bit warmer or cooler than usual.

Emotional Reactivity

You respond quickly to emotional stimuli, both internal and external. You’re a “super probe.” This type often comes with an innate ability to “read” people, but also means you may worry about small things or struggle more with painful emotions. You’re emotionally reactive if the following apply to you:

• You easily pick up on others’ moods and emotions.
• You need a lot of alone time to calm your nervous system and recharge.
• You feel stressed or anxious when you have a lot to do in a short time.
• You get angry or irritable when you’re hungry.
• You’re sensitive to physical pain (have a low pain threshold).
• You try to avoid mistakes because they make you feel intense shame or humiliation.
• You startle easily (have a strong startle reflex).

Aesthetic Sensitivity

You notice details in the world around you, especially in art. You’re a “super aesthete” and deeply appreciate beauty and art. Signs of aesthetic sensitivity include:

• You’re deeply moved by music, literature, painting, film, theater, or a beautifully decorated room or stunning natural landscape.
• You appreciate refined tastes or aromas (like fine wine).
• You notice details others miss.
• You have a rich and vivid inner world.

Sensitivity can show up in all these areas at once, or just one or two.

Michael Pluess, a behavioral scientist at Queen Mary University of London and a leading sensitivity researcher, believes that in addition to these types, some people are more attuned to negative experiences (bad days, loss, trauma), while others are more responsive to positive ones (an inspiring movie or a compliment from a boss). This difference is partly explained by genetic variations. Corina Greven and Judith Homberg, in their book “The Highly Sensitive Brain,” write: “Sensitivity is multifaceted and flexible. It’s influenced by genetic variations and life experience, including childhood.”

This brings us to another cause of sensitivity: childhood experience, including the prenatal period.

What We Learn from the Children of 9/11 Survivors

On the morning of September 11, 2001, tens of thousands of New Yorkers were going about their day near the World Trade Center. About 1,700 of them were pregnant women, according to Annie Murphy Paul in her book “Origins: How the Nine Months Before Birth Shape the Rest of Our Lives.” After the planes hit the towers, these women found themselves in the midst of chaos. Some fought for their lives to escape the towers before they collapsed; others watched the tragedy unfold from nearby buildings. About half of these women were later diagnosed with PTSD, just like many other survivors. Long after the tragedy, their minds remained convinced they were in danger, even when it was over. Many suffered panic attacks, nightmares, and were easily startled by any hint of threat.

That morning, Rachel Yehuda, a PTSD researcher, arrived at the Bronx Veterans Medical Center, about 50 miles from the disaster. Watching the news, she wondered: how would 9/11 affect survivors in the long run? She had spent her career studying Holocaust survivors and Vietnam veterans. In 1993, she opened the world’s first psychiatric clinic for Holocaust survivors. She expected calls from survivors, but was surprised to get far more calls from their children—five times as many. Many in the second generation had PTSD symptoms: nightmares, anxiety, and hypervigilance, even though they hadn’t experienced trauma themselves.

At the time, it was thought that children of trauma survivors were simply scared by their parents’ stories and problems, making them more anxious and sensitive to threats. But Rachel Yehuda thought otherwise. Over the years, she and other scientists studied the impact of trauma on the children of survivors. They found that children whose mothers survived 9/11 had cortisol levels identical to their mothers, and cortisol directly affects the risk of developing PTSD. The effect was strongest if the trauma occurred in the third trimester of pregnancy. Later, researchers found that the risk of PTSD in children increased if their mothers—but not their fathers—had PTSD.

Since the children were too young to be scared by their mothers’ stories, the classic explanation no longer fit. The fact that the effect was strongest when trauma occurred in the third trimester also ruled out the idea that children simply inherited genes for PTSD. So, could mothers pass on traumatic experience to their children before birth?

Messages from Our Ancestors: The Role of Epigenetics

Rachel Yehuda’s research led her to epigenetics—a relatively new science studying how life experience affects genes, their transformation, and expression. It turns out that not only our own experiences, but also those of our ancestors, can influence gene expression. In simple terms, epigenetic markers turn certain genes on or off, helping a species quickly adapt to its environment. Not all these changes are permanent, and the markers don’t alter the DNA code itself.

Imagine your genes as a library. Each book contains instructions for making you who you are. Epigenetics helps decide which books to read and which to leave on the shelf. Traumatic events—war, the Holocaust, 9/11—can change how your genes are expressed, just like everyday things (diet, exercise, aging) can affect gene function.

Epigenetics also helps explain why some people are sensitive and others aren’t. This was shown in a study of prairie voles, small rodents similar to mice. Researcher Jay Belsky exposed some pregnant voles to an aggressive animal (a stressor), while others stayed in normal conditions. Half the baby voles were later raised by nurturing foster parents, who cared for and groomed them. The other half were raised by neglectful parents. When the babies grew up, scientists measured their anxiety levels.

The results were clear. Babies whose mothers were stressed during pregnancy but who were raised by good parents were the least anxious—even less than those whose mothers had calm pregnancies. Babies stressed in the womb and raised by bad parents were the most anxious. Babies who weren’t stressed before birth fell in the middle, regardless of their parents’ behavior.

At first glance, these results seem ordinary, but they were revolutionary. Until then, scientists focused only on the negatives of prenatal stress—like passing trauma to future generations. But sometimes, as one scientist said, “no one asks to observe a child if everything is fine.” That’s why early sensitivity research focused on those in stressful situations.

Jay Belsky, like Michael Pluess, had a different view. Just as the serotonin transporter gene (SERT) can increase genetic plasticity, prenatal stress can send messages to children before birth: “Be alert! The world is wild.” As a result, these children are more sensitive to their environment and better able to handle a changing world. This is the booster effect of sensitivity.

The Ongoing Story: Nature, Nurture, and Sensitivity

In the great debate of nature vs. nurture, the answer is usually “both.” This is especially true for sensitive people, whose genetic predisposition makes them more responsive to upbringing. Amazingly, scientists have even calculated the ratio: genes account for 47% of sensitivity, while 53% comes from environmental factors. Michael Pluess found this by studying twins: their sensitivity levels differed even though their genes were identical. The result: family, school, and social circles influence sensitivity more than other traits and can even increase it.

Early life experience is especially important, though it’s still unclear exactly what makes us more or less sensitive. Pluess says, “This is one of the most important questions we still need to answer.”

A recent study led by Zhi Li aimed to see how children’s sensitivity changes over a year. In a lab set up like a living room, children did puzzles and played. Sometimes, to test their patience, they were given candy and asked to wait before eating it. The researchers watched for signs of sensitivity like creativity, deep thinking, and persistence with tough tasks. Occasionally, they introduced unusual challenges. In one experiment, a stranger in a black plastic bag entered the room for a minute and a half, then left without speaking or looking at the child. The goal was to see if sensitive children would be more scared than less sensitive ones (they weren’t). In another, to test empathy, Zhi Li and her colleagues pretended to hurt themselves and cried out in pain (sensitive children showed more empathy). The children were about three years old at the start; a year later, the experiments were repeated with the same children, now four years old.

The researchers tracked even the smallest reactions. They knew sensitive children are more open to new positive relationships but can also be very reserved. So, Zhi Li’s team looked for small signs, like a child’s desire to please the experimenters by being polite and following instructions carefully. They expected sensitive children to monitor their results and analyze adults’ reactions before making decisions. Overall, they thought sensitive children would be more cautious and careful in controlling their emotions and impulses.

Zhi Li was also interested in the children’s home lives. Was the home unpredictable and chaotic, or safe and stable? Were the parents kind, attentive, and fair, or harsh, impatient, and judgmental? Did they scold their children for mistakes or encourage them? To assess this, researchers observed how mothers discussed recent misbehavior with their children. They also measured the children’s cognitive abilities and behavioral problems like depression, attention issues, and aggression.

After analyzing the results, the researchers found an interesting pattern: the graph formed a U-shape. Children living in extreme conditions (either very caring or very neglectful parents) maintained a high level of sensitivity year after year. Children in neutral or average conditions (not too caring, but not neglectful) saw their sensitivity decrease with age. Like the prairie voles, children raised in supportive environments did best: they showed the highest cognitive abilities and the fewest behavioral problems. Why?

Scientists think it’s related to how the body uses energy. Sensitive people’s brains work at full capacity—they spend more time and energy solving problems. In supportive environments, sensitive children get more energy than they use: sensitivity helps them learn and develop by making the most of their surroundings. In tough environments, sensitivity also helps, but in a different way: they sense threats more acutely and carefully assess situations before acting. Sensitivity helps them anticipate the demands of unpredictable or neglectful caregivers.

Children raised in neutral conditions don’t develop sensitivity because they don’t need it. For them, sensitivity would be a waste of energy: there are no threats to guard against or major lessons to learn. Any sensitive adult will tell you: living with high sensitivity to the environment is exhausting and energy-consuming, not something to take lightly.

So, here’s another key to understanding sensitivity: if you grew up in tough conditions, you developed sensitivity to survive; if you were surrounded by support and acceptance, you became more sensitive to absorb as much benefit and positive experience as possible.

The Advantage of Sensitivity

How important is childhood experience, really? For example, if you didn’t inherit the genetic pattern for sensitivity but your parents often fought, will you become a highly sensitive adult? Not necessarily. Or, if you inherited sensitivity genes but grew up in neutral conditions, does that cancel out your genetic predisposition? Also not necessarily. Early years do influence sensitivity, but genes come first.

Back to Zhi Li’s study: children who already had high sensitivity didn’t change much over the year. Those who started with lower sensitivity increased it in extreme conditions, adapting to their environment.

As Michael Pluess predicted, if sensitivity only developed as a result of trauma, it would be rare. But it’s not—sensitive people are everywhere, making up about 30% of the population, and most had perfectly ordinary childhoods. Pluess concluded that sensitivity has far more advantages than scientists once thought.

After analyzing the research, Pluess identified these advantages. What if the benefits are much broader than researchers assumed, and sensitive people can thrive even in adulthood under the right conditions? Pluess called this the “sensitivity advantage.” His theory: high sensitivity is an adaptive personality trait that allows people to get the most out of any kind of support.

To test his theory, Pluess studied depression, focusing not on the serotonin transporter gene but directly on sensitivity. The study mainly involved teenagers from one of England’s poorest areas, most of whom hadn’t grown up in stable conditions, increasing their risk of depression. If the sensitivity advantage is real, the most sensitive teens should be the ones to overcome depression.

During the study, the teens participated in a four-month depression intervention program. They learned to recognize symptoms and build resilience. They were tested for depression before, during, and after the program. The results were striking. At first, it seemed the program had little effect—until researchers looked at sensitivity levels. Less sensitive teens got nothing from the program, but for the more sensitive ones, it was a ticket to a better life. They overcame depression during the study and stayed in remission for at least a year. The program’s results changed everything. The most disadvantaged kids didn’t just survive thanks to their sensitivity—they outperformed their peers in every way.

Similar results have been found for sensitive people of all ages and in different situations. Sensitive adults on the verge of divorce are more likely to save their marriage if they seek help. Sensitive children who are well cared for show excellent social skills and learn better than their less sensitive peers in the same conditions. Sensitive children and adults also show strong altruism. Therapists agree: sensitive people of any age make more progress in therapy and get more out of each session. As adults, sensitive people show higher resilience to stress—the opposite of what’s expected. It turns out, they’re not “hot-house orchids” who can only survive in perfect conditions. They’re more like succulents—absorbing every drop of goodness until they bloom.