Smell

Introduction to Smell

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0:34Hello, I have a favourite aftershave. By the by, I feel a bit self-conscious calling it an aftershave because I don't shave. But then I feel even more self-conscious calling it a cologne because that feels like me pretending to be American. Which leaves me the word perfume. But then again, being the age I am, that feels like a female word. When I come out of the shower and I'm off to do something a bit posh, do I splash on perfume? Well, yes I do.

1:05Because at least perfume connects with what the stuff actually does, which is produce fumes.

Describing Perfume

1:11So I'll start again. Be brave, Michael. I have a favourite perfume. Now for the next problem. How do I describe my favourite perfume? No, I don't mean say the brand name. What words are in my word bank to convey to you listeners the smell? Well, I think it smells a bit lemony. I think it's quite sharp. Without being pungent, I think it's fresh. If I had to match it with a colour, I'd say it was green because I think it smells to me a bit like some woodland in spring.

1:45Is there a touch of evergreen leaves about it? A bit of pine in there? How am I doing? Are you getting a sense of what I smell like when I put this perfume on? You'll notice that in order for me to try to convey this smell, I've had to use words that aren't really very much to do with smell. Like lemony. Sharp. Fresh. And I've done that thing that we all do when we struggle to describe things. I've gone for some similes. I said it's like a woodland. And then as a last resort, I cheated.

2:15I guessed some potential ingredients. Evergreen leaves. And pine. After I came up with this description, I did some research to find the actual real ingredients. A test, if you like. This is what I found. Top notes. Rosemary. Clary sage. Brazilian rosewood. And lavender. Middle notes. Geranium. Clove. And tonka bean. Base notes. Oak moss. Honey. Musk. Amber. And tobacco.

2:45Hmm. What does this tell me? Either I've got a lousy sense of smell. Or I'm pretty hopeless at describing smells. Or both. I think this also tells me that I need some help with this. And my guest on Word of Mouth is just the person I think will be able to do this. She is Asfa Majeed, Professor of Cognitive Science at the University of Oxford. Welcome to the programme, Asfa. It's great to be here. Now, you've done a lot of work in this field of the language of smells, Asfa. How did I do with my description of my perfume?

3:16I mean, it conjured something, for sure. So, you conveyed aspects of what I should expect if I were to smell the perfume myself. Good. Okay. Well, I'll take that as a compliment, if I may. I brought it along, actually. So, can I squeeze a bit? Shall I squeeze it on me or you? You can do it on me. Here we go. Okay. Here we go.

3:38What do you think? It smells like man. Oh, right. Man. Is that a smell name, I wonder? Yes. It smells like man. It does. Yes. Anything else have we got? Anything different word other than the ones I used? I think, well, it's interesting. So, the question is always, what are we describing it for? When you look at what happens within the perfume industry, you can see that the descriptions that perfumers give are very different to those that marketers will create because they're

4:09trying to do different things with language. So, look, maybe we should take a step back and do a bit of biology so we all know what we're talking about.

Biology of Smell

4:17What is smell? So, smell, there's not one simple answer for this, philosophers will disagree, but for now, let's just say it's when molecules go into your nose and they attach to receptors. Just at the back of your nose, there's a sheet of something like skin that has receptors on it and they attach to that and that gives us the sense of smell. And those receptors go into the brain? They go into the brain, so the olfactory bulb. Yes. And then from there, it's connecting to different parts of the brain, depending on what information

4:50we're getting from it. So, there's a close connection to the limbic system, so to emotion. It also connects to taste because smell and taste are very closely related. And then other aspects of our knowledge as well. And from the age of nought onwards, we presumably start attaching words to those sensations. I can call them sensations, can't I? You can. And so, one of the interesting things that we find when we've looked at this is that young

5:21children in the UK are often interested in the sense of smell and their remark on it. They'll say something about it and the parent will shut it down. They'll say, that's disgusting. Put it down. Go away. And they won't further continue to talk about it. Really? So, even when there's an interest from the child, the parents don't really, or the caregivers don't really continue talking about it. And that's something that's reflected more broadly. So, if we compare how often people talk about visual things or auditory things or taste or smells,

5:52what we find is we talk a lot about what we see and very rarely about what we smell. Now, we think of some species as being very good at smelling, most notably dogs. We often use that. We use the dogs for the purpose of hunting, don't we, and forensics. Does the human species have a good or bad sense of smell in relation to other species? We have a much better sense of smell than has perhaps people think. We can detect molecules at very, very low concentrations.

6:25We can also discriminate, so tell apart two odors very easily. So, early estimates thought perhaps we could discriminate 40,000 odors. Now, it's guessed that it's a trillion or more. Yeah. So, we can discriminate more with smells than we can different colours, which are in the order of a few million. A trillion smells, but surely we don't have a trillion words. No, English doesn't seem to be particularly good at expressing different smell qualities.

6:56I mean, but we have phrases. I mean, if you go into the woods, there's lots and lots of smells. You might have bluebells and you might have leaves and you have different kinds of trees. And if you're with a group of people, they might say, oh, yeah, I can smell the bluebell. Oh, yes, that pine smell. So, people make up phrases, don't they, and attach them to the objects and plants and things they can see. Yes?

Talking About Smells

7:17Yeah.

Talking About Smells

7:18So, it's helpful to differentiate different ways of talking about smells. So, I can convey what a specific object smells like by referring to that object. So, this smells like a rose. This smells like a banana. So, that's one way that we can talk about smells, but we don't seem to have dedicated vocabulary to convey distinct olfactory qualities in the way that we do for colour, say. So, if I want to describe a colour, if I say something's red or green or blue, it's picking at a quality.

7:50You don't know anything about the object, but you know what that hue is that I'm referring to. So, red could be a fire engine, it could be a traffic light. It could be, exactly. It's transferable. It's transferable, and it's picking at a quality that we perceive. So, going back to smell, the terms that we do have don't seem to quite do the same thing. So, if we think about things like stinky or fragrant, they're definitely telling us that something is good or bad.

8:23But unlike colour terms, it doesn't really seem to be about the object it's describing. It seems to be a subjective thing. I could say, oh, this perfume you think is really fragrant, I think is stinky, and both can be true. So, the description doesn't seem to be about the object itself, but how I perceive that object. This seems very deep in human development, though, because it seems to be to do with survival. Yeah, biologists think it's actually so important that the main thing that it's doing is approach or avoidance.

8:58That's what you need the olfactory system for. Is this something that I should go towards or try to get away from? But I think that our candidate quality terms for smell in English, one of the best ones, in my view, is something like musty. So, musty does pick out, maybe it's a bad smell, but it picks out a particular quality. So, it's the smell of a room that hasn't been opened for a long time or a book. My books. Your books.

9:28On my shelves, they're musty. Particularly musty. So, there is a quality that you can recognise that it's picking up. Yes. Well, I put out a call on social media asking listeners and friends to come up with some words. Let's see what they've got. Ah, Dorothy Granville said foisty for a damp smell. Have you heard that one? I have heard it. And maybe it's closely capturing the same kind of semantic category as musty. Yes. Sounds like it. Foisty, musty.

10:01Yes. And here's a Scots one, which you'll like. Slang for smelly. Bogging. Yeah. Bad smell. You know that one? Yeah. Yeah. Minging, which is all part of the same thing. Humming and honking. So, Scots there seems to be quite prolific in just saying, woof, I don't want to smell that. Yeah. There are brilliant ways of saying stinky. Yes. And then a bit like foisty and musty, I've got here frowzy from Christina Casey. And she says that's washing that's been left too long before being hung up.

10:31So, it's that stale off-water smell sort of thing. And she says that the word in this context was introduced to me by my partner, whose parents are from Jamaica. So, that may have come from the Caribbean. Amazing. That's definitely a recognisable smell. It is, isn't it? Mm-hmm. Yeah. It's that thing when you put it on and you just wonder where it's coming from and then it's sort of rising out of your T-shirt or something. Mandy Holloway gives us stench, which I'd forgotten about. Noxious.

11:00Noisome. I didn't know that. Yeah. Noisome stink. Of course, we do have the word aroma. Did you mention aroma before? That's, I remember there used to be my parents used to have a coffee and it said the aroma was sealed in. And me and my brother used to discuss how you would seal in aroma in a coffee tin, I think it was. Yeah. Lee Johnson has got the word orduous. I know the word odorous. And my dad always used to walk into our bedroom and say, this place is malodorous, which we used to think was very funny.

11:32So, he says that's a fabulously weighty onomatopoeic adjective that is sadly underused now, says Lee. Dave Klink, which is a very onomatopoeic name itself, isn't it? He's got a whole set of words for foul things. I was going to say foul words. Foustie, reeking, toiking, honking, humming, guff, howfin, baufin, miffy and funky. Some of those are great because they're referring to the response that a bad smell would give you rather than the actual odour as well.

12:04So, that they make you want to vomit. Yes. Or wretch. And as I say, it does seem that we're much more prolific with the bad smells than we are with the nice ones. And that's something that we see across languages, that all communities seem to want to distinguish between different types of bad smells. And that's maybe got something to do with the fact that there's different actions that you might want to take with different types of bad smells. I was thinking about some basic topics of conversation in families, well, amongst friends, even strangers.

12:41Something like the weather. When we talk about the weather, we talk about the temperature. We talk about the light, the wind, what the sky looks like. But we don't often talk about the smell of the weather, do we? You know, when it's just rained or after a long period of sun. Those are different smells, aren't they? If I go into my garden, after a long period of sun, there's a smell that comes off the... I can't even describe it, but the smell off the lawn is different from when it just rains straight after that long period of sun.

13:12But I don't think I've got words to describe that. Well, there's a great term that a couple of chemists coined to describe the smell of the soil after rain, which is petrichor. Yes, I love that smell. Yeah, it's a great smell. And so they made up this word to be able to describe that smell, which now seems to have come into ordinary English as well. Yes. What are the roots of that word? Petrichor. So the term petro they took from Greek for earth and ichor for tenuous essence is how they describe it in their paper.

13:45Very nice. Very nice. Now, you say in one of your papers that it's long been believed that smell is ineffable, that is difficult or impossible to put into words. I wondered whether we could test that theory. A little bird has told me, you've got something for me.

Smell Recognition Test

14:01Yes, I brought some smells for you to see if you can describe them. So they're less complicated than the perfume. So it should be really easy for you to be able to describe them to me. Oh, right. No pressure then. Yeah, thank you. No pressure. Okay, go on then. Are you going to squirt it or am I going to wipe it? How are we going to do this? Ah, right. So here comes the producer and she's bringing in little silver cans, little silver cups that look a bit like she's going to spray me with yoghurt. Poking holes in. You don't get to see what's in it.

14:32That would be too easy for you. Oh, I see. So you're going to have to use your sense of smell. So the toothpick is making holes in these little yoghurt pots. This is pot number one. Oh, I'd say straight away that's coffee. I can smell it from here. That's an excellent coffee. Right, but now I've done the object, but I haven't said what it, what the smell. That's fine. Let's see how good you are at recognising the objects from their smell. Right, that's okay. I just, I wonder, because there's different kinds of coffee, you know, I can smell that, you know,

15:02I should be able to decide whether that's medium or heavy roast or whatever or instant. So I'd say I have a very nice feeling about coffee because my parents drunk it, my wife drinks it, I drank it up until I was ill and now I never drink it. And so I basically, I have a yearning for this. So I'm basically like kind of on the wagon for this. One of the measures of the ineffability of smell is not just that we don't have the quality words for it, but even in cases like this where you have the object, typically in a study like this,

15:37people are only able to recognise the smell object around half the time. So even though the smells that I've given you are familiar smells and you were able to do the coffee really well, people find this very challenging. So let's see how you do on smell number two. Okay, smell number two coming up.

15:58Ah, yes, yes, this is harder. This, actually talking of yoghurt, this does smell a bit like blueberry yoghurt. Hang on.

16:10I'm not going to get nearer. It's funny because it actually relies on memory. I'm thinking back to smells I remember, aren't I? So these words for smells are stored in my memory bank, aren't they? They are, just like olive language. It isn't blueberry muffin or blueberry yoghurt, but what is it? I believe that's the cinnamon. Oh, no. So you are not even close on this one. Oh, I love cinnamon. I like cinnamon, what are those called?

16:42Those cinnamon bun things. They're called cinnamon buns. They are. That's good. I'm glad I'm correct with the terminology there at least. Yeah, that's cinnamon. Let me have a look. I'll get a check. Oh, it is. How could I think blueberry and cinnamon are the same? So that's not unusual. So when we test people in the lab, that's exactly the kind of error that you see that seems just utterly perplexing. How can an odour that's familiar, that's recognisable, now that you know what it is, it's clear.

17:12And yet, when you can't see the object, you can't see it and you're only relying on your sense of smell, you can be far away as that. So would my excuse be that it was like free association, that I thought buns and muffins and that I eat cinnamon buns and I eat blueberry muffins and I got muddled in my linguistic part of my brain? That's an interesting hypothesis. One thing that people have proposed is that it may have something to do with how the brain is organised.

17:42According to one set of researchers, it's because the information from smell areas of the brain connect to the language area of the brain too quickly. So that there's only two synapses from going from the olfactory information to the language areas. So there's not enough time for the brain to process what's happening. You're getting there too quickly. So you need to do some of the semantic processing, getting the meanings before you get to the label. And that might be what's causing problems for us when we're trying to describe smells. Oh, I love that. That's fascinating.

18:14Now on with the next one.

18:17Oh, yes, that's a tincture. That's the stuff we used to rub on our legs after we played rugby, like Vicks. It's like an ointment that you rub on, certainly before and after we played rugby, we used to rub our legs with this stuff. Well, I hope you weren't putting this on your legs. It's toothpaste. Oh, well, maybe the same stuff's in it. It's liniment. That's the word I was looking for. Well, it could have some of the same stuff that's in liniment that is in a toothpaste.

18:49Well, this I don't know well enough to argue with you. So let's just say you were on the right track. Yes. Now, I'm obviously talking in English and so are you. So what we're talking about, does this vary across cultures in the world? In other words, do some people talk about smell more than others or in different ways from each other? Well, it certainly does vary quite substantially across cultures. But in fieldwork that I've done with colleagues, with the Jahai, who are a small group of hunter-gatherers in the Malay Peninsula,

19:24we found that they were as good at describing smells as they were describing colours. Ah, right. So that's very different. Very different. And they were better at describing smells than English speakers, even though the smells that we took to test them were familiar to our English speakers. And not necessarily to the Jahai. Right. Now, have you got some examples? Can you say the words and tell us how they translate? Yeah. So they have a term, Lutput, which is for fragrant, pleasant smells.

19:56So flowers, durian is an example of a Lutput smell, even though it's not very pleasant to Western noses. Bearcat that smells like popcorn some of the time. So these are all Lutput smells. But that's different from another fragrant smell, which is a Jungos. So Jungos smells are fragrantly edible sorts of smells. So cooked chicken, coffee even. And are these words transferable in the way that we were talking about how red is transferable?

20:28These words are transferable across different... That's right. So these are terms that pick out classes of smells. I've just given you some illustrative examples of the sorts of things that they might apply to. They only refer to smell, so they can't be used for taste. And they're not related to any object. Have you got some more examples there? Yeah, so maybe at the other end you have haet, which are really awful smells. So feces, rotten meat, prawn, shrimp paste, smell of tiger.

21:01So these things are both edible things and not edible things are all grouped together. So there's a really bad smells. But that's different to Ba'u smells, which are kind of musty sorts of smells. So that can apply to an old building, some species of mushrooms, stale food, like cooked cabbage, stale rice, things like that. Or Jungos smells, which are a little bit stinging. So a bat cave or bats would smell like this. Petrol smoke. Now that's interesting because I wouldn't link petrol with bat bats.

21:34I mean, I've smelt bat droppings in a barn and I wouldn't link that to petrol. Now that's quite interesting, isn't it? Because you've done this research with hunter-gatherers, can we talk with any authority about how a sense of smell has evolved

Evolution of Smell Language

21:48and our language has evolved from the time everyone was a hunter-gatherer? It's difficult to do that with the current data. What we can see now, after having worked on this for many years, is that we find smell language. In pretty much every part of the world, with two notable exceptions. So one, we haven't found a large lexicon of smell terms. So large here means more than two or three terms. We haven't found a large lexicon for smell terms in Europe or in Australia.

22:22And I don't know right now whether those are genuine gaps or whether that's just a documentation gap because people have just assumed it's not there and so nobody's really looked for it. But we find it everywhere else. And so I have changed from asking, why do the Jahai have it? To now asking, well, why do we not have smell language? I think that is the more interesting question to ask, given that it appears in many different contexts. So you find smell lexicons in languages like Thai, which is spoken by millions of people.

22:56Even if you test undergraduates in Thailand, they will know the smell words of their language. So there's something funny happening in our language and culture that we don't seem to be using these terms. I wonder, does this link to the possibility that urbanisation has done something to our sense of smell? I mean, people have talked about how we spend a huge amount of time and money deodorising ourselves. I mean, I brought out my perfume, but we also spend money on stopping ourselves smelling, don't we? We have antiperspirant, we have deodorant, we have baths and showers.

23:29So we lose our natural body smells. We only have to go on holiday for a week and say, not shower. And then we suddenly discover all sorts of very fascinating smells about ourselves. Well, I mean, day to day, we don't do that anymore. I mean, coming into the BBC, people don't want to smell. Smell each other. So we don't do that. So have we de-nuanced ourselves? So we looked at this in a historical corpus of English to see if there was more smell language from the 1800s to 2000s. So was it the case that there was more smell language early on that has disappeared around the turn of the 20th century?

24:05And that does not seem to be the case. So at least from the 1800s to the 2000s, it looks like smell language was equally infrequent in written text, which is all we have access to. Because anything that people were saying, we don't have recordings from those times, we won't know. Yes. Now, I started by talking about perfume. Can you talk a bit more about, say, wine tasters and cookery experts and the perfume makers? I mean, can we say, for example, that they've developed their sense of smell and therefore have a wider range of language to express this?

24:40I mean, they have to for their jobs? They do indeed. So we have done some work with wine and coffee experts. And when we test wine experts on their wine language, what we find is that they do show more agreement in how they talk about the smells and tastes of wine than laypeople do. But it's only for wines. So when we test them with different types of coffees or even ordinary objects like the smell of banana or the smell of cinnamon, they're no better than laypeople.

25:14So what they seem to have developed is a vocabulary only for wine smells and tastes that doesn't generalise. So this is quite important because this tells us that this is an acquired language and an acquired sensory ability. Actually, what this made me think of is that the word that wine tasters use about the smell of wine, they say nose, don't they? They do indeed. They say it's got a good nose or an indifferent nose. And you can become a nose by developing these skills. Yes.

25:44And on the matter of subjectivity, now I know, most people I know, they like the smell of white wine. I can't stand it. So I find it quite horrible. All white wines. Pretty well, whereas I love the smell of red wine. I don't drink either because I'm now more or less teetotal. So, but you pass red wine under me and I'm, mmm, and I could have a go at describing it. But white wine, I'm just, thank you very much. No, just keep it away from me. I don't like it. It smells acrid. There we are. There's an interesting word we haven't used yet.

26:15It's one of them. That's kind of a little bit sour. Yeah. And stale, acrid. Is that right? Yes. It's good. I mean, you can, another study that we did, we took descriptions of wines that experts had produced, and then we try to see if the descriptions that people are providing are informative, we should be able to figure out what the wine is that they're referring to just from the description alone. So we took lots of reviews from the internet, and then we try to see, can we predict from the language, whether it's a red or a white wine, whether it's a Chardonnay or a Riesling, whether it's a cheap or an expensive wine.

26:53And in fact, we can. So just from the descriptions themselves, we can figure out what type of wine it is and whether it's cheap or expensive as well. Interesting. Pop quiz. What's in your kid's lunchbox? At Whole Foods Market, they've already done the studying. Over 300 food ingredients are banned from their shelves. No hydronated fats in the peanut butter and no high fructose corn syrup in the cookies. And for sandwiches, there are no synthetic nitrates or nitrites in any of their deli meat.

27:26So you can pack lunchboxes with peace of mind. Get back to school ready at Whole Foods Market. Well, you're listening to Word of Mouth, and as you may know, the programme is produced in partnership with The Open University. If you'd like to listen to my conversation with The Open University about the words we use, my own language journey and what I've learnt from the stories behind how we speak, you can visit the BBC Radio 4 Word of Mouth programme page and follow the links to The Open University. As for, we often end Word of Mouth programmes with some language that expresses farewell, a parting, a well-wishing, that sort of thing.

28:04Is there a smelly version of that? I can't think of a word that would do it, but smell definitely figures in all sorts of greetings. So when we shake hands, we're exchanging our chemical signature with one another. If you look at what people do once they have shaken hands, you see quite commonly people bring their hand to their face as if they're going to smell the other person. Or if you were born in the 90s, you might smell you later.

28:33Yes, why not? So, listeners, smell you later. And thanks very much indeed, Professor Asfamajid. Thank you.