When you are naked, Kelley Swain tells me, you find that you are more aware of the world around you. The way the light moves, the air currents that swirl around, the grumbling noise your stomach makes when it’s close to lunchtime. You will notice how warm it is. Or how cold. Maybe, if like Swain you have to take off your glasses to pose your eyesight might be a little less clear but all your other senses compensate. In short, being in the nude is a sensory experience. “All these things that you feel and notice that you might not be as sensitive to with your clothes on,” she says.

And, of course, there are the smells. The scent of the studio – turps, oil paints, dusty fabrics – that are part and parcel of being a life model.

Swain is a 31-year-old American expat. She is a writer, a poet and until recently the subject matter for painters. She has spent days unclothed in artists’ studios being re-embodied on canvas in oils and pastels and ink.

She has written a book, The Naked Muse, about that experience. It’s a cool, thoughtful piece of work that will make you think about what it takes to do so, its challenges and rewards. And, inevitably, it’s a book about the body. About how we represent it and how we think about it. In a culture that is increasingly reducing life experience to a series of screens – that is to some degree effectively disembodying us – that seems worth considering.

And so here we are, Swain and I, sitting in a restaurant near the Museum of London on a wet Wednesday afternoon discussing the difference between the nude and the erotic, ideas of body image, bohemianism and creativity, the desire for posterity, the current fashion for tattooed life models, the artist she’d most like to have posed for in the entirety of art history (Vermeer maybe, she says, or Velazquez) and the joys of naked swimming (she’s in favour of it).

The first thing people always say when they learn that she is a life model, Swain says, is: “’I couldn’t possibly do that.’ That’s the general reaction. Or: ‘Hey, I used to do that.’” I am most definitely in the former camp, I tell her. But then I’m a middle-aged man with middle-aged spread and when I was younger I had bad skin. I’d never have had the confidence. “If you did go for it you might find you felt much more confident because of it,” Swain suggests. “I think that is very possible, that is often a really powerful thing to have happen.”

Has that happened to her? “It has changed the way I think about my body, but I do think I went into it because I was quite comfortable with it. What it did for me was by treating my body as this object to be painted it actually helped combine my head and my body. Because I’m often in my head, often not thinking about my body.

“I was an awkward teenager. I would run into things and knock things over and was very clumsy. So I think at my most awkward I can feel very graceless. But by being in this role I feel very graceful and I hope I am a bit more graceful for it.”

She doesn’t seem lacking in any grace today. She’s a pretty, thoughtful, eloquent young woman. Anything but an object. But that, of course, as she says, is her role as the artists’ model. It’s a strange, liminal thing to be, she suggests. “When they were painting I was the model and when they were on a break I would be in my robe as Kelley.”

HeraldScotland:

The first time she modelled was at university in the States. The experience was “quite giddy”, she remembers. “I had a lot of friends who were artists and dancers and a lot of dancers are often artists’ models because they know how to stand and hold themselves and move well. And one of my friends who was regularly modelling for art classes couldn’t do it at the last minute and rang me up and asked, ‘Can you fill in for me?’ And I said, ‘OK, why not? Let’s see how it goes.’” This was in a women’s college, she didn’t know anyone in the class particularly and the teacher had been teaching “longer than I had been alive”, so she found the experience perfectly comfortable. “But I think I was hyper-aware of the newness.”

Even so, she kept saying yes, in the States for a couple of years and then after she moved to London. Why? “It was a mixture of curiosity and convenience. I really loved art and art history. I’m not very good at painting and drawing so I was learning a lot because I was sitting in on these classes for free. Or better than that – getting paid.”

What does it take to pose other than self-confidence, you might ask? A level of fitness, it seems, an awareness of how to stand or pose. And how to hold a pose for many, many minutes. (Sometimes artists forget that the model is not an object. Or not only.)

“I ended up falling into the classical category because I have pale skin and dark hair before I went grey in the last couple of years. I just sort of got painted in these classical poses. There are some where your arm goes dead and certain ones that really made me think differently about paintings

I look at because I will now say, ‘How was she doing that? Was she leaning on a pole? Or really in pain? Is the painting done incorrectly? That stance is not anatomically possible.’”

What has been the most difficult pose? “It was an odalisque. A prostitute, basically. A woman in the nude. She was recumbent, lounging back, her arm twisted. It just wasn’t working and when it’s not working it’s the worst. You know you look uncomfortable and you know that’s going to translate for the artist. You’ll look miserable in the painting. It does come across.”

The worst thing is being cold, she says. Then there are the times that you know the sofa you’re lounging on was just hoiked out of a skip not long before you lay down. “But I like the bohemian feeling of an art studio that if you walk around barefoot your feet get covered in black charcoal dust, if you get a cup of tea at all the cup is going to be covered in paint. There is a feeling of creativity and community in that which I think is lovely and I like to be part of that.”

That’s also why she’s never bothered if the paintings that emerge don’t match her own sense of self. “I say it isn’t about me, it’s about the artists. I have sat for people of all skill levels, including beginners. I can’t be worried about how they make me look in a picture because they’re practising their artwork, the study of the body and anatomy and muscles and stance, so if I end up looking terrible in someone’s drawing, it’s OK. They need to practise. It’s fine.”

Swain grew up by the sea in Connecticut. She didn’t see much art as a kid but remembers a trip to Washington DC when she was 14 and seeing a John Singer Sergeant exhibition which blew her away. His paintings were romantic and glossy and Parisian “and that was just the height of sexiness to a teenage American”.

When she started modelling she had, she says, a very young vision of art. “An American college-girl vision.” She had a poster of John Everett Millais’s Ophelia on her dorm room wall. She had a big thing for the Pre-Raphaelites, “and the thought of going to England was the best thing I could imagine”.

HeraldScotland:

But she was a poet too. Modelling was not the only creative act she did. Not even the main one. Still, I wonder, is there a desire for posterity in her decision to model? “Oh always. I think everybody has the desire for posterity. It’s a weird posterity because there are really bad paintings of me.” One female painter told her that all her canvases ended up rotting on the back porch. “So there are probably some of me rotting on the back porch like Dorian Grey. That’s interesting. That’s what I’m going to come to eventually as well. Eventually the only images left of me are those paintings. That’s not who I was. It’s one way I looked according to somebody.”

She moved to the UK because she met someone. “We were married and then weren’t. The typical American story, I think.” Was being a life model ever a problem with the people she knew and loved? “I feel like I’ve been extremely lucky in absolutely being encouraged,” she says. “My parents were kind of hippies turned yuppies. Pretty laidback. My mum was the first person who knew I was going to be modelling and she [said]: ‘Great. I’m glad you’re so comfortable with yourself.’

“I was aware when I decided to write the book it was a way to think about and talk about being naked in a way that’s acceptable and not prurient and not kind of scandalous. People definitely want to talk about it.”

We want to talk about it, she says, but in a context that means it’s not embarrassing or uncomfortable and life modelling is one of those. “It’s funny. One of the photographers I work with was doing a project about nudism and I said, ‘I don’t think of myself as a nudist.’ I don’t feel a particular need or preference to be in the nude. And I need to be clothed so often in this country because it’s so cold.”

In the end of course we can talk about anatomy and context and craft and creativity when it comes to life modelling but at the same time, it’s difficult to avoid the fact that what we are looking at when we look at the results of that modelling is naked skin. It is an exposure.

HeraldScotland:

In her book Swain asks herself if she is exhibiting herself when she poses and probes the distinction between “nude” and “erotic”. I’ve decided to test this idea. Before I arrived here, I tell Swain, I popped into the National Gallery and picked up some postcards. She has to tell me which each is, nude or erotic. I show her a detail from Botticelli’s Venus and Mars. A nude male. “Oh gosh, it’s funny. That’s more erotic to me,” she says. “It’s this naked young man in a loin cloth. He’s very sexy and very exposed. It’s the posture I think that makes it very sexy.”

He’s looking a bit post-coital there, I suggest. “Yeah and it’s very vulnerable.”

Next up is Velazquez’s Rokeby Venus, that famous rear view of a naked woman looking into a mirror. A classic example of a painting for the male gaze.

HeraldScotland:

“She’s for his pleasure,” agrees Swain. “But we will put the mirror in the picture because that makes it a lesson about vanity. ‘Tut, tut, young lady.’”

An example of Velazquez having his cake and eating it then? “Exactly. I’d say that’s a nude. She’s modest, she’s beautiful and she’s a lot less vulnerable. She would see someone coming.”

HeraldScotland:

We look at Bronzino’s An Allegory with Venus and Cupid, a painting that screams sex (albeit of a disturbing kind) and the artist’s model in her comes out. “It’s a bit stiff, that one. That couldn’t have been comfortable. It’s one of the weirdest pictures actually. She points to a body that doesn’t seem to belong to the head on top of it. “I don’t know where that body is going or how that head could be part of that. And there are floating heads. It’s really disturbing.”

Here’s my favourite, I say. Peter Paul Rubens’s Portrait of Susanna Lunden (although the National Gallery adds a question mark to that attribution), aka The Straw Hat, which isn’t a nude because Susanna has a covering of filmy clothes and a bold black feathered cap (though no straw that I can see).

HeraldScotland:

Now that’s erotic, I suggest. “It’s the cleavage, isn’t it?” Swain smiles. It might be, I agree.

The story we so often tell about artists and models is a sexual one, of course. It plays into our notions of bohemianism (whatever that word might mean now). And so the very idea of the muse can be problematic. We read into it an objectification. Not always wrongly. Swain has just been reading about Kiki de Montparnasse, the lover and subject of Surrealist artist Man Ray. It doesn’t seem like the healthiest of relationships, she suggests.

“He was the one who would decide every morning what colour eyebrows she would paint on. Some people might find that romantic. I think it’s very creepy. That’s very controlling.”

That is not necessarily the norm. More troubling might be the way the relationship between artist and model colours our views of them in posterity. And so Lizzie Siddall, the muse who became ill with possible pneumonia while posing in a bath for Millais’s painting Ophelia, the painting on Swain’s dorm room wall, is now solely remembered for the paintings she appears in. And yet Siddall was a painter too.

Siddall the artist is largely unremembered however. Siddall the model is. Historical memory has claimed her as an adjunct to the great men who painted her.

Swain has never modelled for anyone famous enough for that to be an issue. Still, she concedes that writing the book is an act of reclamation over her image, her body even.

In the end we are all bodies. We are obsessed with how we look, what we wear. Maybe now in an age of instant images more than ever before. “Yeah, the digital visual culture is dangerous in that way,” Swain agrees, “because it’s so highly curated – to use a loathsome word that’s misused all the time – it’s so highly selective. Only the best selfie of me will be put online.

“And I think that’s very dangerous for younger people or people who aren’t sure how they’re feeling even on a given day. It’s very easy to look outwardly and feel everyone else is perfectly wonderful. And that’s just because everyone else is editing out what they don’t like or what they don’t want to show.”

Art, though, offers a way to see through that. To see the reality of the body and the attraction of that reality. Artists, Swain argues, are looking at the flesh and form of us and finding beauty in all its imperfections.

“I hope that that makes them more compassionate towards themselves and other people,” she says.

That’s the question then. Do artists see the best in us? And, if so, can we educate ourselves to do so too?

Look in the mirror. What do you see? What it is to be human perhaps. That’s the naked truth of it.

The Naked Muse by Kelley Swain is published by Valley Press, priced £8.99.