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How does sign language work?

Have you ever wondered how exactly sign language works? Or why signers’ faces are so expressive? Or if you can shout in sign language? Prof. Lorraine Leeson answers all our questions!


Welcome to the very first episode of What Do You Want To Know? My name is Jenny, and I'll be your host over this series. A couple of months ago, I asked people for examples of the kind of questions that kids asked them. And it turns out that kids ask lots of questions! And some of them are really profound and really curious! And while the answers might seem obvious, when you actually start trying to answer them, you often find yourself falling down a rabbit hole of 'but why...?' We got questions about superheroes, about traffic lights, about how lifts work, about space, and life and death and everything in between. So we had tremendous plans to make a shiny fancy podcast in a shiny fancy studio, and then a few days before we were due to start recording... well you can guess what happened. So we're leaning in to the DIY aspect of it now! If the episodes sound a little bit less than polished then that's because they are. We're using the internet and very little equipment! And if you think they sound good in spite of that, then that will be down to the wizardry of the wonderful people at Headstuff who've been helping us all along the way.

For this first episode, we're trying to answer the question 'how does sign language work?' Most of us will have had some exposure to sign language, whether it's the signed version of the evening news or a viral video of an interpreter at a Stormzy gig. And it might seem like how sign language works is pretty obvious: you use your hands. But what are your hands doing? And do you use the rest of your body? And why are the sign language users' faces so expressive when they're signing? Do you see I mean about falling down a rabbit hole?

I asked Lorraine Leeson to help me answer this question. Lorraine is a Professor of Deaf Studies at the Centre for Deaf Studies, and the School of Linguistic, Speech and Communication Sciences in Trinity College Dublin. She has published widely on aspects of the linguistics of signed languages, and has a specific interest in Irish Sign Language and the area of sign language interpreting. Lorraine was a member of the first cohort of professionally trained Irish Sign Language interpreters in Ireland, and she continues to interpret occasionally. I once even spotted her on the telly interpreting for Michael D.

I began by asking Lorraine 'how does sign language work?'

LORRAINE: Well, sign languages are languages that are expressed through the body - actually, so are spoken languages, but what happens with sign language is that you are using larger articulators. You're using the hands, but also the torso, and the head, the eyes, the mouth, the cheeks... All of that comes into play when you're expressing information in a signed language.

JENNY: Ok, so I suppose all of us would be familiar with sign language interpreters, say, on the news or things like that that we've seen, and the question that always comes to me is 'what is the face doing?' Because the face is very expressive on people using sign, so I've always been like 'what is it doing?!'

LORRAINE: That's the one thing that people often get completely wrong. They think, 'oh, your one is very expressive, aren't they!' when in fact what's happening is you're using the face for grammatical purpose. So, your eye gaze is really important. Where you look: if you look towards a particular location in signing space, what you're doing is you are effectively using a definite article. You're saying it's this thing that I'm focussing on, or this is the point that I'm volitionally acting towards. You're using your eyebrows to impart meaning. So, if you raise your eyebrows, tilt your head back a little, you're marking something as a topic. So you're saying 'you know that thing that we were talking about?' so shared information is being presented and then your head returns to a normal sort of resting position and you present some more information and you're saying this is what's really important for us to know about that, or here's this new piece of information I want to give you about that.
You can furrow your brows and lean forward a little bit, and you do that normally when you're asking particular kinds of questions. So if you're asking questions like 'who are you, where are you from, how did that happen, why is this important' then normally to mark those questions your brows are furrowed and you're looking forward. If you wanted to ask a question where you were expecting a yes or no response, then you would have your eyebrows raised. What you do with your eyes and your eyebrows is pretty important!

Also, with the mouth in fact you do lots of really interesting things. If you were to stick your tongue out a little bit, as if you are saying 'the' in a very pronounced way, but if you keep your tongue out and make a sort of a little airy sound actually that's marking that you - you normally would have that facial expression co-occurring with a verb on your hands. And what you're doing is that mouth pattern is functioning as an adverb so it's saying that you were careless about something or you weren't paying enough attention. Whereas if you made the mouth pattern like 'mmhmm' what that says is that everything was done in the normal way. And another one that's used very frequently is if you sort of bare your teeth a little bit like you're grinning or you don't want to open your mouth, what that's saying is that something was very difficult. So when you put those particular mouth patterns with particular verbs you're actually modifying the meaning of the verb.

JENNY: Ok, so does the face help to convey tone or are there other ways that you convey tone using sign languages?

LORRAINE: That's a brilliant question. You can indeed. You can ramp up meaning by being more insistent with your facial expression, you know so you can exaggerate facial expression in order to do things like you would with tone so if you wanted to say, you know, 'wow, that's amazing!!' well then you could do something like really widen your eyes but you would also extend the movement of the sign. So just as you know with a word you can say 'that's amazing!' or something like that - of course I'm completely exaggerating - but equally you can lengthen the duration of the sign in order to give emphasis to it. 

JENNY: Wow. Ok, so then, can you shout in sign language?

LORRAINE: Oh yes you can! So if you're signing in a normal way, in adult conversation, you use a certain amount of space. And younger deaf people tend to use more space. They own their space more than older deaf people. So, if you have a normal sort of tone in order to exaggerate it what you do is you sign bigger. It can be shouting or it can be articulated clearly, so if you're having an argument you will have hands flying, and using space more strenuously. But equally if you were to present at a conference where you've got 400 sign language users in the audience, you want to make sure that you're heard - as in seen - at the back of the room and so therefore you're also going to use more signing space. You'll also for those purposes, though, slow things down a little, so pace would be important and that's also to make sure that your audience is with you because what is seen is heard effectively.

And equally then if you wanted to whisper, you can also do that. Normally what that means is that you reduce your signing space completely, but you might also move it to the side of your body and down lower so that it might be under a table, for example, so you can say something to the person sitting next to you - if you don't want somebody to see. I was once at a meeting where I saw a deaf person who wanted to get out of that meeting and felt that it wasn't going anywhere, lift their hand, pretend to stretch, and over their head they literally finger spelled to somebody sitting opposite them to say 'there's no hope' i.e. let's get out of here. And so that's also an effective strategy, and well outside the normal ways of articulating!

JENNY: I can see lots of people learning specific signs to try and get out of meetings now! Just to pick up on something that you mentioned there, about the history of sign language. How long has sign language been a recognised language in Ireland and what kind of status has it had over the years?

LORRAINE: That's a big question! At the moment I'm reading a paper that is co-authored by one of my colleagues John Bosco Conoma with a wonderful PhD student called Cormac Leonard. They are trying to uncover the historic roots of Irish Sign Language because we know that since the schools for the deaf were established in the early 1800s, that there has been documented evidence of deaf kids using sign languages, but we don't know what happened before that because records are sparse, because sign languages are visual, they don't have a written form.

It's really difficult to reconstruct what sign languages looked like, but what Cormac has done is he's gone back through the historical records and has been able to trace references to deaf people in Irish institutions - so, coming in contact with the state - and there are references made in all of those records to the use of sign languages. So we know for hundreds of years, well before there were any schools established there were deaf people in Ireland who were signing. We don't really know what that looked like exactly, and so it's only really since people started to try and write down, to record, and describe individual signs in the 1800s that we have any sense of what individual signs might have looked like, and from there we can try and track how things have changed over time.

JENNY: I'm assuming then that other countries have their own versions of sign language, so could sign language users from those different countries, could they communicate with each other with relative ease? Or are they specific to each country?

LORRAINE: Well, it depends. If you've been exposed to a lot of sign languages, well then you're probably going to have a much easier time in getting by with another sign language user from another place. I've met and I've seen deaf people from many countries, where there would be absolutely zero point of contact between the spoken languages, being able to have at least basic conversations around where they're from and what they do, and their experience of life. But that said, at the same time, the languages are very different. While they all use space to represent space and use movement through space, use hand shapes moving through signing space to represent how people move or how things move through space, that's only going to get you so far. Because that's great for, maybe, concrete ideas, and maybe you can get to some more abstract ideas through that, but you have to really also have something else that gets you over that hurdle.

There is a thing that we call International Sign, but that is what we would consider to be a 'contact phenomenon' whereby if you're using let's say Flemish Sign Language or Adamorobe Sign Language and I'm using Irish Sign Language, what we would have to do is we would have to negotiate meaning as we're going through a conversation, so there would be an opportunity for repetition, we would have to slow down, we would also potentially draw on American Sign Language which is like the lingua franca - it's probably like Latin was, or French has been in previous times - and you would move between strategies and linguistic devices to try and overcome the language barrier. But there are people who come together very regularly and so have regularised their mechanisms for communicating across linguistic and cultural borders. One great example is the European Union of the Deaf, which is a pan-national body that represents all of the national associations of deaf people in Europe, and when they come together as a board they use what they call 'International Sign' and that works very effectively for them because they have that repeated contact. That repeated contact and building up of a shared repertoire helps, whereas if you had an incidental first meeting with somebody from a very different place that might be very difficult to do.

JENNY: Within each of those, so within Irish Sign Language, British Sign Language, or the sign language of wherever a particular person is from, are there accents or dialects or, you know, regional variations the way that we would say 'oh, that person is definitely from Kerry!' when you hear them speak. Are you able to identify where someone is from by the way that they sign?

LORRAINE: You can. In some countries, yes. But I think, fundamentally, what it comes back to is where did you go to school. What's really, really interesting is here in Ireland traditionally there were two main schools for the deaf. There was St Joseph's School for deaf boys in Cabra, and St Mary's School for deaf girls in Cabra. And so as a result of that - they're about a mile up the road from each other - and when they were established, the nuns had gone to France and they had learned about the French approach to teaching deaf kids and brought that home. The Christian Brothers set up their school ten years later and they deliberately decided that they wanted to differentiate the way the boys would sign from the way the girls would sign. And so they went out of their way to make the vocabulary less "girly" I suppose, and they went through this process of differentiating out the vocabulary of the language.

Over time those two schools were like little language islands, and if you talk to anybody in zoology they'll tell you when you've got two islands effectively you're going to allow for things to develop differently and evolve differently. You effectively have this female variant of signs in the girls' school and the male variant in the boys' school and they became really quite different. You had different signs for days of the week, for things like nouns like girls and boys, different signs for Easter, different signs for colour terms, and on and on it went to the point that, of course, being Ireland and being in a patriarchal society, the boys - the men - decided that their variety was the proper variety and, therefore, the school leavers from the girls' school were encouraged to ditch what they were using and adopt the male variant as the dominant and the more prestigious variant. And that was very interesting. So that kind of went on for a long time.

In the late 1970s, there was a nun called Sister Nicholas Griffey who was very influential in Ireland for many, many reasons, but she and this deaf man called Stan Foran who was a very key person in the deaf community at the time, they were involved in an attempt to what they called 'unify the language.' So they tried to bring together the two variants and... well, it wasn't terribly successful because of course people use what they use. I think the British Council or some language council in the UK in the 1920s wanted to call what we call roundabouts 'gyratory circuses' and that never caught on! Just because somebody tells you you should do something a particular way doesn't mean you're going to use that in your everyday language. So while the deaf women would in broader company generally adopt the male signs, the male lexicon, when they were with themselves they were still using the female variant of course, because it's about language, it's about identity, it's about culture, it's about belonging. And so that expression of self maintained over time. So while the degree of variation has reduced there, it's still lovely now to see that the most commonly signs for days of the week are actually the women's variety. That gives me great pleasure I have to tell you! But then there are other signs that have won out, like the male sign for boots and shoes is the more dominant variety for some reason. So there are tonnes of interesting stuff that happens in language and who knows why and how these things actually play out.

JENNY: So, following on from that then, is there slang or contractions or can you abbreviate things in sign the way that we would kind of chop up spoken language?

LORRAINE: You can indeed. You have got lots of slang, in fact - not just even slang, but also that carrying on of identity or taking language that was used in one form and then bringing it forward and reusing it in a different way. One of the other things that has happened with these gendered varieties that we've had in Irish Sign Language, is that we see members of the LGBTQ community are using what were previously old women's signs, if you like, without knowing it, and they have brought that in and adopted them as vocabulary that's used amongst their community. So you've got this recycling of language, but also this broadening out and using it in a new way so it's very creative and very effective.

JENNY: You mentioned finger spelling earlier, and some of us have heard of Lámh sign, and I'm just wondering what is the difference between sign language and Lámh sign?

LORRAINE: Lámh actually borrows its vocabulary from Irish Sign Language. Lámh would typically use open hand shapes so that would be like a flat hand as if you're about to wave to somebody, that hand shape is much easier to articulate than if you also had to pull together the thumb and the little finger which is like the scouts' sign, you know the peak hand shape, but that can be quite tricky to articulate. So you would expect that those tricky hand shapes would be eliminated from the vocabulary, and so it might mean that signs would be reimagined, they would be - when I say simplified, I mean that the complexity of the hand shape would be reduced, and so there would be deliberate efforts to try and do that so that somebody who might have articulation issues, or hand mobility issues, would be more easily able to articulate those signs.

JENNY: An accessibility kind of thing?

LORRAINE: I mean it's also about little kids, even for little deaf kids with deaf parents who are acquiring a sign language naturally, those hand shapes are hand shapes that they don't "get" until they're older because it's just a matter of being able to pronounce things in a particular way. So just as for spoken languages there are certain words or certain combinations of sounds that are harder to produce, equally there are certain signs, certain hand shapes, that are harder to produce.

JENNY: So how does someone actually go about learning sign language?

LORRAINE: Well, if you want to learn a sign language, we actually in Trinity have some evening classes that you can come to! But there are also many good sign language classes that are delivered by the Irish Deaf Society and by the Irish Sign Language Academy. Irish Sign Language was only officially recognised in Ireland in 2017, with the Irish Sign Language Act, and that doesn't commence as a piece of legislation until December 2020 in fact. So in the interim, sure there are other laws that govern the provision of information in certain settings but in order to tie up loose ends where deaf people are finding it difficult to access information and were not being considered as a group in society who deserve access to information through their language, the power of the Irish Sign Language Act will be that it will oblige public sector providers to make sure that there's at least interpretation and other information made accessible through Irish Sign Language. But while I'm talking about the recognition piece, what's interesting, however, is that at European level sign languages were recognised through the European Parliament as early as 1988.

JENNY: I don't know how to sign, so what is the best way for me to communicate with a sign language user?

LORRAINE: I would say what you need to do is remember that hearing people - that would be you and me, people who hear - that we use our bodies all the time too. We gesture when we speak in face to face communication, so we should leverage that and we should not be afraid to gesture, to slow down, to repeat ourselves, but just make sure that you are visible, that you don't over articulate, that you're looking at the person, that you're not afraid to gesture. Don't be afraid to write something down, you know, or use your phone to write a text message and try and be open to engaging. Don't be afraid to repeat or to ask for repetition, and give it a go!

JENNY: You also mentioned about there not being very many sign language teachers, but we haven't really talked about interpreting yet, and I'm guessing that would be a part of the Sign Language Act as well. Do you need special training to be a sign language interpreter or can anyone who knows sign language act as an interpreter?

LORRAINE: One of the great things about the ISL Act is that it requires the establishment of a register of sign language interpreters, and it will require public sector bodies to only use people who are members of that register to provide their interpretation. That's so important because unfortunately over time we have had people rock up in hospitals, in courts, in all sorts of settings that are very impactful on people's lives, and say ‘I'm here to sign’ and when you inquire it turns out that they may have the best intentions in the world but they could perhaps have had a couple of sign language classes. You can imagine, I mean, if you've gone to a French class for a year you're not ready to walk in to a court room and interpret. Because knowing a language and interpreting or translating between languages, they're very different things. You can be very bilingual and still not be a good interpreter. You can grow up bilingually and still not be a good interpreter because it's a very intricate set of skills that you need to develop around handling language, about moving between - you know - thinking about the meaning in the first language, and how you would articulate that in the second language with minimal influence on how the ideas that are being presented by a speaker or many speakers are being affected because you don't want to warp a message.

Inevitably when you're moving between languages there has to be... there's a shift maybe in cultural perspective, or in the perspective of the speaker, but you want to do your damnedest to minimise that, and to make sure also that there's sort of fluency and cultural appropriateness in the interaction as it moves forward. And you also want to do your very best to not influence the outcome of the proceedings because when you're interpreting, certainly, it's not about you. It's about the other parties to the event, and those things are really, really important. There's the ethical issues as well as the linguistic issues, as well as the interpretation issues so if you know a few signs, really, you shouldn't be offering to interpret.

JENNY: So what does that mean then for say major news events? I'm thinking everything that's going on in the country at the moment with the Covid-19 outbreak, and occasionally you'll see the sign language interpreter on screen and then sometimes the shot will cut away or whatever, and they're not always visible or... what does it mean - how should those broadcasts be made accessible for sign language users?

LORRAINE: One of the big problems for deaf community members is that they have to keep pushing and pushing hard to ensure that they have access to information. You and I can turn on the radio, can turn on the telly, and you have easy access to that information. But if you're deaf, even with the best will in the world, the bodies who are bringing in interpreters, they'll have them at a live event and as you said, you know, the cameraperson will pan away and they don't seem to realise that if you're not seeing a sign language interpreter at all times, you're not hearing the message.

You have to see it in order to hear it when you're talking about a sign language.

So what should happen is that you have the interpreter on screen, visible from at least the waist up to above their head in a good screen pattern and not as a teeny weeny little dot at the bottom of the screen somewhere. They need to have ample space and visibility so that somebody can literally read what's on the signer's body. Cutting away means that you just don't have that message, or you have - it's like having really poor sound quality where your message is interrupted or there's static on the line. That would really annoy you and I, and so therefore this cutting away really upsets deaf people. And it means they do not have access to information which is highly problematic in a situation like the one we're in.

JENNY: I'm going to end with one question to you. What is your favourite thing about being a researcher?

LORRAINE: I've been thinking about this question, you know, myself in terms of 'why do we do what we do!' What I love about being a researcher is that its a bit like being a detective. You... like, I'm a linguist. That's what my original training is, as a linguist and as an interpreter, and so for me, you know, when I'm practicing as an interpreter, something will come up either in terms of the interaction or in terms of language that makes me think 'I wonder how that works.' I go away and I look and see if anybody talked about this for other sign languages, try and figure out what's the missing piece to the puzzle. What account of the phenomenon that we're describing makes sense, and how can we articulate that and bring it forward.

I think the other thing that I love about being a researcher is the fact that we're able to build up a body of literature to document the experiences of deaf people and the way the languages work. When I first started out as a student in the early 1990s, I could find one paper written about Irish Sign Language, and that had been written by an anthropologist from the United States who had come to Ireland to document the gendered differences between the men and the women in the Irish deaf community. Today, we have many, many, many pieces of empirical research that's there and I think that that's really… the mission is to make sure that there is a body of knowledge there to go forward that people can build on, that they can critique. But if you don't write about a language it's much more vulnerable, if a language is undocumented it's much more likely to diminish and to be overlooked. So what we really want to do is to try and make sure that Irish Sign Language, now that it's recognised, is robust and that we build resources, because there aren't enough resources. I want to help to build those resources over time.

JENNY: That's amazing. Thanks for talking to me today, Lorraine!

LORRAINE: Thank you for the opportunity, Jenny! It's been a real pleasure.


JENNY: My thanks to Lorraine for chatting with me and answering my questions. Confession time: I was the one who wanted to know how sign language works, so we'll be answering questions posed by big kids too! If you want to find out more, go to where you'll be able to find a full transcript of this episode, along with some links to the things that Lorraine was talking about.

Thanks also to Conor Reid for all his help with the production side of things, and thank you for listening! Tune in next time to find out more of what you never realised you wanted to know!

Lorraine Leeson

Lorraine Leeson is Professor in Deaf Studies at the Centre for Deaf Studies, and currently serves as Associate Dean of Research (2018-). Her research work is multidisciplinary in nature, influenced by her background in Deaf Studies, Gender Studies and Linguistics. She has published widely on aspects of the linguistics and applied linguistics of signed languages with a specific interest in Irish Sign Language and in the area of sign language interpreting.