Isn't HSP Just a Yasashii Person?
Japan Turned Sensitivity Into a Diagnosis; Korea Turned Inattention Into One
1. A Word I Met on note.com
On days I've used my head too much, I find myself reading warm everyday stories — about love, family, small moments at home — to gather myself again. note.com is full of those stories. Small incidents at work, things a child said, the small gestures of a parent — all of it becomes a post and goes up on the site.
While reading those stories, I kept running into the word "HSP."
It was a word I'd never heard before. A word I had never encountered in my life was being used like everyday vocabulary in another society. It appeared as naturally as "depression" or "burnout." In the self-introduction of someone working at a café, in the diary of someone struggling with work, in the recollections of someone who had broken up with a loved one — the same word kept showing up.
When I looked it up, HSP turned out to stand for "Highly Sensitive Person." It is a concept first proposed in 1996 by the American clinical psychologist Elaine Aron. About 15 to 20 percent of the population is estimated to have this kind of nervous system. Aron defined four characteristics of an HSP: deep processing of stimuli, being easily overwhelmed by overstimulation, emotional intensity, and sensitivity to subtle stimuli.
When you look at these four characteristics quietly, a particular thought arises. They read less like a diagnostic name and more like a description of someone's personality.
Isn't this just a yasashii person?
2. Who Does HSP Point To?
Let me sketch these four characteristics as a single person.
This is someone who keeps chewing on the same stimulus long after others have let it go. A single word another person brushed past stays in this person's head for days. A scene from a movie watched yesterday, the look a colleague made in last week's meeting, something someone said months ago — all of it keeps returning. The first characteristic: deep processing.
This person tires faster than others in loud places, bright places, crowded places. In the same café where someone else can stay for two hours, this person's head feels heavy after thirty minutes. The second characteristic: easily overwhelmed by overstimulation.
This person responds deeply to other people's feelings. Cries longer at sad movies. When a friend's face darkens, this person's mood darkens with it. In a setting where someone else is being criticized, this person feels the weight of it as if it were aimed at them. The third characteristic: emotional intensity.
This person picks up on subtle changes others miss. The small shift in someone's expression, the faint change in the room's atmosphere, the small label inside a piece of clothing, a quiet sound in the air — they register more vividly. The fourth characteristic: sensitivity to subtle stimuli.
Roughly 15 to 20 percent of people are estimated to have this kind of nervous system. They are not people who have received a medical diagnosis. They are simply people who, having recognized this pattern in themselves, have started calling themselves HSP.
3. Only Japan Took This Word In
In 2018, Japanese psychiatric social worker Yuki Takeda published 『「気がつきすぎて疲れる」が驚くほどなくなる「繊細さん」の本』 — roughly, "The Book of the Sensitive Person: How the Exhausting Habit of Noticing Too Much Surprisingly Disappears." The book sold over 600,000 copies in Japan alone.
Since then, the expression 「繊細さん」 (sensaisan) has become part of everyday Japanese vocabulary. note.com, X, radio programs, magazine features — it appears everywhere. People started introducing themselves with "私は繊細さんです" ("I am a sensaisan"). In cafés, in hair salons, in bookstores. Even people who had never been diagnosed with anything began defining themselves as 繊細さん.
This phenomenon did not happen at this scale outside Japan. The same concept was published as books in the United States, the United Kingdom, Germany, and France, but Japan is almost the only place where it reached the level of a social phenomenon. HSP is used in Korea too, but nowhere near as widely as in Japan.
Why Japan? That question is the starting point of this essay.
4. A Different Word Is in the Air in Korea
While HSP was rising on Japanese social media, a different word was rising on Korean Instagram reels: ADHD.
"I'm ADHD" has become a new way for young Koreans to introduce themselves. Content like "A day in the life of someone with ADHD," "If your friend has ADHD, they do this," "People faking ADHD versus actual ADHD" goes up every day. In short videos, young people describe themselves as "scattered nervous systems," "impulsive nervous systems," "nervous systems that only see the present."
ADHD and HSP are both, in substantial part, genetically inherited traits of the nervous system. But the fact that a nervous system is genetic, and the fact of how the person carrying that nervous system ends up living, are not the same story. The same nervous system can flow naturally with daily life in one society, and collide with daily life every day in another. As those collisions pile up, the name the person comes to call themselves begins to shift.
In the same period, two countries in the same East Asian region are defining themselves through different words. One side calls itself "sensitive." The other calls itself "inattentive."
This cannot be a coincidence.
5. Why ADHD in Korea, and HSP in Japan?
Two countries in the same region, in the same era, putting different nervous-system names on themselves. Korea: ADHD. Japan: HSP. Where does this difference come from?
The answer lies in the fact that the two societies ask different things of their people. A nervous system meets misalignment in different places depending on what the surrounding society demands of it. When societies demand different things, the shape of the misalignment also differs.
What does Korean society ask for? Speed. Immediate response, clear results, intensity of competition. From the turnover rate of restaurants, to the decision speed of companies, to the reply speed of messages, daily life in Korea moves fast. Inside this society, a person calibrates their nervous system to that pace every day. A nervous system whose rhythm differs from that pace meets overload every day — and the name of that overload becomes ADHD on the Instagram of Korean youth.
What Japanese society asks for has a different texture. Reading the moods of strangers, smoothing over conflict, not letting another person's heart be hurt. The server at the restaurant, the stranger next to you on the subway, the colleague at the meeting. Inside this society, a person finely calibrates themselves to other people's moods every day. A nervous system that does this calibration too well exhausts its own resources — and the name of that exhaustion becomes HSP in Japan.
Here is why the two diagnostic names mirror the two societies. Even when the same nervous system exists in both, the misalignment that comes into focus is different, and so a different word rises to the surface. The misalignment Korea encounters most often was given the name ADHD. The fatigue Japan encounters most often was given the name HSP.
6. The Virtue Called Yasashii
It is not a coincidence that Japanese society asks for that texture. That texture comes from the most central virtue Japanese society has long cultivated. That virtue is summed up in a single word: 優しい(yasashii).
優しい(yasashii) is not exactly the same as the Korean "sangnyang-hada" or the English "kind." 優しい(yasashii) carries within it "soft," "delicate," "does not hurt others," and "handles things carefully" all at once. When a person is described as 優しい(yasashii), it doesn't simply mean they are friendly. It means that person calibrates themselves so as not to hurt the heart of another.
The Japanese language has many words for this virtue. 「気配り」 (anticipating someone's mood and acting on it), 「察し」 (sensing what wasn't said), 「気が利く」 (being quick to notice), 「思いやり」 (the heart that takes others into account). All of these carry positive weight and are used often in evaluating people in everyday life. How rich a society's vocabulary is around a particular value tends to reveal how deeply that society has cultivated it. Japanese has a remarkably rich vocabulary for this texture.
The place 優しい(yasashii) holds in Japanese culture is far larger than the place "good-hearted" holds in Korean culture. In Japanese literature, films, and song lyrics, 優しい(yasashii) is one of the most frequent adjectives. When describing a marriage partner, recommending a friend, remembering someone who has passed — the highest praise of a person's character often comes down to that single word.
When you watch the daily life of a 優しい(yasashii) person closely, one thing becomes visible. They notice others' moods just a little more carefully. They shrink their own space so others won't feel uncomfortable. They hold back their words to avoid interrupting. They adjust their expression so no shadow falls on someone else's heart. They process stimuli deeply, respond strongly to others' emotions, and pick up on subtle changes.
7. HSP Is a Phenomenon That Comes From Being Worn Out by Yasashii
Seen this way, a conclusion arises. HSP, rather than being a defect in any one person's nervous system, is closer to a social phenomenon that emerges naturally when a society's virtue runs deep through everyday life. Japan has cultivated 優しい(yasashii) deeply as a virtue, and in the place where people who live by calibrating themselves to that texture every day grow tired, the name HSP rose into view.
ADHD has the same structure. Korea has cultivated rapid speed and instant responsiveness as the texture of daily life. People whose nervous-system rhythm differs from that speed encounter daily moments of mismatch. When those moments pile up, they come to describe themselves as "scattered" or "impulsive," and into that place the English medical term ADHD entered. It is one phenomenon that arises because Korean society's tempo flows through every part of daily life.
What both diagnostic names point to, in the end, is a single fact. The social environment has a substantial influence on a person's inner life. Depending on which society a nervous system is placed in — what virtues, what speeds it encounters every day — the name a person comes to call themselves changes. Japan has cultivated yasashii, and so HSP rose where people grew tired by that texture. Korea has cultivated speed, and so ADHD rose where people grew out of step with that tempo.
This conclusion is one I have arrived at in similar places in essays on ADHD, on depression, and on hikikomori. The traits of a nervous system cannot be separated from society. The virtues and the everyday textures a society has cultivated shape the inner lives of the people within it. And where those inner lives meet society as misalignment, a particular name rises into view.
8. Closing
There was a short post on note.com, written by a Japanese person about themselves. In his work meetings, he wrote, he reads other people's moods so deeply that he can never finish saying his own opinion. After the meeting ends, every expression and every word from it stays in his head and won't fade for days. So he calls himself a 繊細さん (sensaisan). Reading that post, a single thought stayed with me. This person isn't "sensitive." He is closer to someone faithful, every single day, to the most cherished virtue of Japanese society. In the place where that long-accumulated faithfulness has worn him down, society has come to summon the English abbreviation HSP.
As someone who lives in Korean society, I often meet moments where I wish there were just a little more of that texture in everyday life — the texture of caring, finely, about a stranger's mood. At restaurants, on subways, on the street. Somehow, each time, Japan comes to mind. Not that Japan is a better society. Even knowing that the people there are growing tired because of that texture, the 優しい(yasashii) that reaches even to strangers seems all the more precious in this era.
Isn't HSP just a yasashii person? The reason this single line is not as light a question as it seems lies right here. Inside what looks like an English medical abbreviation, there is a virtue a society has long cultivated, and a person who is faithful to that virtue every day.
References
Aron, E. N. (1996). The Highly Sensitive Person: How to Thrive When the World Overwhelms You. Broadway Books.
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Acevedo, B. P., Aron, E. N., Aron, A., Sangster, M. D., Collins, N., & Brown, L. L. (2014). The highly sensitive brain: an fMRI study of sensory processing sensitivity and response to others' emotions. Brain and Behavior, 4(4), 580–594.
Lionetti, F., Aron, A., Aron, E. N., Burns, G. L., Jagiellowicz, J., & Pluess, M. (2018). Dandelions, tulips and orchids: evidence for the existence of low-sensitive, medium-sensitive and high-sensitive individuals. Translational Psychiatry, 8(1), 24.
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Seungwon An / Wonbrand / https://wonbrand.co.kr