A sensitivity expert speaks
Professor Michael Pluess is a pioneering developmental psychologist in the fast-growing field of sensitivity studies.
Welcome to my weekly newsletter building a supportive community for Highly Sensitive People (HSPs). This is the first in an occasional series of interviews with leading researchers, authors and therapists working in the sensitivity field.
When Michael Pluess started his research career 15 years ago, the conventional wisdom among psychologists was that some people are just born unlucky.
Researchers observed that a subset of children seemed to suffer more profound impacts from adverse experiences than their hardier playground peers.
To Pluess, this apparently random vulnerability didn’t make complete sense. Surely, any extra susceptibility to stress should have long since vanished from the gene pool. What possible purpose could it serve?
Now a professor in developmental psychology at Queen Mary University of London, the Swiss national is a leading figure in the fast-growing field of sensitivity studies. And his search for answers is helping to cast the benefits that go with being a Highly Sensitive Person (HSP) in a clearer light.
An avid musician who spent several years touring professionally as a bass guitarist in his 20s, Pluess never set out to be a researcher. But he realised he loved deep conversations more than performing, and took up psychology with the intention of practising as a therapist. A few years later, he started a PhD in London under Professor Jay Belsky, a renowned American expert on child development, and his interest in sensitivity began to grow.
Intuitive appeal
Belsky had a theory that children differ in how strongly their development is shaped by their environment, with more “susceptible” children gaining extra benefit from positive experiences, as well as suffering disproportionately from adverse events. Belsky’s approach held a more intuitive appeal for Pluess than the tendency in traditional psychology to focus almost exclusively on the negative impacts of bad experiences in so-called vulnerable children.
In his doctoral research, Pluess took up the question of why some children seemed more “susceptible.” As Belsky’s theory predicted, he found that certain genes and temperament traits were associated with an increased vulnerability to harsh or neglectful care, but also a heightened responsiveness to warm and supportive parenting.
In 2008, Pluess reached out to the American psychologist Dr Elaine Aron, who coined the term HSP. He wondered whether his work with Belsky on “Differential Susceptibility” might overlap with her work on “Sensory Processing Sensitivity” — the way HSPs may have exceptionally vivid experiences of sounds, smells, tastes, colours and touch.
Brand new thinking
It was the start of a long and productive collaboration with Elaine Aron and her husband Arthur Aron, also a well-known psychologist. As Pluess had suspected, children who seemed more “susceptible” to stress also scored highly for sensory sensitivity.
In a field littered with abstruse technical jargon, the term researchers use to describe these highly sensitive children is as simple as it is poetic. They are known as “orchids” – and just like this delicate variety of flower, they may struggle if they don’t grow up in exactly the right conditions. But if these children receive proper nurturing, they can flourish in exceptional ways.
“The most fascinating thing was that it really changed my thinking from the established fact that some people are more vulnerable to developing problems when they experience stress, to an understanding that maybe these same people also benefit much more from positive experiences,” Pluess tells The HSP Revolution. “That’s the reason they exist: There’s a disadvantage to being sensitive, and there is also a benefit. That to me was brand new thinking. And really refreshing. I was just amazed the first time that I heard it in that way.”
In psychology jargon, benefiting from high sensitivity is known as “vantage sensitivity” — a term developed by Pluess and Belsky. The concept has helped Pluess’ work towards integrating various theories of sensitivity into a comprehensive “Environmental Sensitivity” framework. In a measure of the growing interest in the field, he now co-hosts monthly webinars with doctoral students around the world.
“Being sensitive does not equal problems,” Pluess says. “But it means you may need to be a bit more careful than someone else about how you regulate yourself to an optimal level.”
His work is making waves beyond academia. Pluess was recently quoted in an article in the Guardian on HSPs, and up to 4,000 people a month visit sensitivityresearch.com, a collaborative research platform he runs with other psychologists that offers a free online sensitivity test.
The HSP Revolution spoke with Pluess to learn how the emerging findings in sensitivity research can help HSPs. Here is an edited version of our chat:
What drew you to sensitivity research?
“I was interested in how to prevent the development of mental health problems. I started my research looking at prenatal exposure to stress, and how that has an impact on a child. And it didn’t quite make sense to me that there are some children who are simply born more vulnerable to stress. From an evolutionary perspective, why would that exist over time? Those genes should have fallen out of the gene pool.
“Once I learned about Differential Susceptibility, I realised: “Oh, there are some people who are simply more sensitive: They are more affected by negative experiences, but also benefit more from positive experiences. That was just completely a game-changer of how I was looking at vulnerability.
“At that time, I didn’t know much about sensitivity. The term I used was “Differential Susceptibility.” That’s still the technically correct term that people use when describing susceptibility to both positive and negative experiences.
“Very early on, I reached out to Elaine Aron (the American psychologist who coined the term HSP). I knew about her work through a friend. Although it wasn’t mainstream, I made that link between her Sensory Processing Sensitivity work, and Differential Susceptibility.
“The most fascinating thing was that it really changed my thinking from the established fact that some people are more vulnerable to developing problems when they experience stress, to an understanding that maybe these same people also benefit much more from positive experiences. There’s a disadvantage to being sensitive, and there is also a benefit.”
So that was a surprising discovery?
“That to me was brand new thinking. And really refreshing. I was just amazed the first time that I heard it in that way.
“So I’ve found the perspective of Differential Susceptibility fascinating and refreshing, and I did my PhD on that.”
Is this related to the idea that there are basically three groups of children — “orchids” (highly sensitive children), “dandelions” (the most resilient children) and “tulips” (those somewhere in between)?
“The idea of ‘orchids’ and ‘dandelions’ actually comes from a theory called Biological Sensitivity to Context. The researchers behind that theory are the Americans Bruce Ellis and Tom Boyce. In one of their papers, in 2005, they linked the idea that people differ in their sensitivity to terminology that’s used in Swedish culture, where people refer to ‘orchid’ children and ‘dandelion’ children.
“They picked it up and then mentioned it to describe the idea that orchid children might be more vulnerable. At the same time, if they are in the right environment, they can do particularly well. In Swedish culture there seems to have been some understanding of that but I don’t know exactly how Ellis and Boyce found out about it.
“Myself and some colleagues ran advanced statistical analyses in large samples and we consistently found three groups: orchids and dandelions, and a middle group that was actually the largest one. We had to find a flower that would fit between those, and we thought tulip might be a good one. I didn’t come up with the flower metaphor though (laughs). It’s not perfect, and sometimes people criticize it. Obviously, orchids growing in the UK are much more fragile than they would be in their natural habitat. So the metaphor really works mostly in a Western context.
“We generally find that the population is about 30% orchids, 30% dandelions and 40% in the middle. That’s what we find with sensitivity questionnaires.”
The figure Elaine Aron gives is that 20% of the population are HSPs?
“I think she concluded 20% based on research on child temperament by (American psychologist) Jerome Kagan. But according to the recent research we conducted together with Elaine Arron and others, it seems to be higher than 20%, closer to 30%.”
What does this research mean in practical terms for parents?
“What is relevant is that parents understand that children may differ in their sensitivity, which means one of their children might need slightly different parenting than another child.
“What we do find is that it’s important for sensitive children to have parents who provide them with structure and help them to self-regulate rather than just leaving them by themselves. We found that in a study where we didn’t measure sensitivity with a questionnaire — we used the gold standard in psychology, which is observation. These children were observed by psychologists and rated very carefully on their behaviours. (The children were observed years ago in video-recorded interactions in a U.S. research project known as the Stony Brook Temperament Study).”
What is research saying about sensitivity and the brain?
“What’s really interesting is a recent study that Bianca Acevedo (a researcher specialising in sensitivity at UC Santa Barbara) published. It showed that the more sensitive people are, the more their brain seems to be interconnected. That’s called resting state connectivity: When people just relax and try to think about nothing. You can look at how the different brain areas are connected with each other. There are also certain brain areas that seem to be more active in more sensitive people.
“Myself and some colleagues have also looked at the amygdala — a small part of the brain that is responsive to threat signals, and also to positive stimuli. What we did in our study is to look at the volume of the amygdala – how dense is it, how many neurons there are. We found that boys with a larger amygdala were more affected by experiences during their development, compared to boys with a smaller amygdala. It was a relatively small sample — though larger than other studies — and it’s something that needs to be investigated further.”
The suggestion is that children born with a larger amygdala could be more sensitive?
“Yes. We also know that the prenatal environment can influences the size of the amygdala. It will be influenced by genetic factors, but also by environmental factors. For example, if the mother is stressed during pregnancy, it can have an impact on the child’s amygdala.”
What are the key practical takeaways from sensitivity research for HSPs?
“We are in the process of collecting data on coping strategies — that’s really key. We all have to regulate our emotions, our thoughts, our behaviours, and people that are highly sensitive are more impacted by what they experience in their surroundings. They need to up their game when it comes to self-regulation and coping.
“We did find in one study that if genetically sensitive people grow up in a difficult environment, then they will be more affected by stress later on. But if they grow up in a better environment, then they are less affected by stress later on – which suggests that it is possible for genetically sensitive people to acquire resilience.
“And I think the way they do that is by developing helpful coping strategies. What do you do with sensory overload? What do you do when exposed to criticism? Maybe I need some down time. And I know that I need a certain number of hours of sleep, and as long as I get that I’m fine — I can deal with all the challenges that come my way. Or I may need to change my way of thinking, and adopt ways of thinking that are helpful for dealing with stuff that otherwise would overwhelm me.”
So there is research into coping strategies taking place now?
“Yes. The idea is that although the genetic components of sensitivity could be similar between sensitive people, the different histories that they have growing up may shape their sensitivity in different ways. So someone growing up in more difficult surroundings may develop a sensitivity that is more focused on recognizing threats, and therefore might show a bit more negative emotionality, and end up being more vigilant. Whereas somebody growing up in more supportive environment, may develop vantage sensitivity — sensitivity to positive experiences — and more easily benefit from opportunities that present themselves.
“Being sensitive does not equal problems. But it means you may need to be a bit more careful than someone else about how you regulate yourself to an optimal level.”
You were featured in a Guardian article a few months ago. How far are you seeing this research influencing the wider culture?
“When I started out, there were only a few research papers on sensitivity in scientific journals. And I think that has increased, and I think in the mainstream there’s a lot of interest. More and more people are writing books and blogs, such as The Highly Sensitive Refuge, and there are various Instagram accounts with tens of thousands of followers. Our website sensitivityresearch.com gets 3,000-4,000 people visiting a month, and most of them want to complete the sensitivity test. There’s a lot of interest in people finding out about their sensitivity.”
What do you most appreciate about being an HSP?
“I am sensitive but don’t really identify as an HSP — that’s probably my dislike of categories, even though I created some of them myself. I’m just below the orchid: a high-scoring tulip, and I don’t feel my sensitivity is keeping me back from anything. I’m in a competitive academic environment. I do experience stress, I do experience uncomfortable emotions — I experience all of that but I’m usually able to deal with it.
“That’s maybe because I grew up in a supportive environment. It wasn’t an environment where there was no challenge — but I was able to get the support that I wanted when I needed it.
“A lot of highly sensitive people maybe do quite well when they are self-employed, they get to decide what they want to do. That works well with therapists, coaches, artists and academics, because you’re able to really engage with something in depth, and you do that without anyone sort of pushing you. You get to explore, being led by your interests.”
Is there anything about HSPs you’d like people to understand better?
“Being highly sensitive is not a diagnosis — and it’s also not something superior. HSPs are not better people than other people. It’s just one of many personality traits. Often introversion and sensitivity are put together. But actually there’s quite a few people that are highly sensitive but extraverted. On the measure that we have now, they would score in the middle — they are quite sociable and outgoing but they need downtime, they get tired when they are with too many people. When you have a group of highly sensitive people, they may have some similarities — but in other ways they might be quite different from each other.
“In the scientific world there was initially a bit of scepticism about sensitivity. I would say that we’re winning over more and more people through our research. I see now other people not linked to our group doing work on sensitivity, but there’s still a lot of work to do.”