Something you might find surprising if you delve into sign language literature is the familiarity of the terminology. When you see the word phonology you probably think about the study of sounds. You might even be shocked to discover that there is phonology for sign languages. This post will explain how the phonological terms of spoken languages can be applied to sign languages.
Spoken language phonology identifies the smallest contrastive sound units of language. In spoken languages phonemes differ in various ways (for example, place of articulation, voicing or aspiration). We know that phonemes are contrastive in a certain language when we find minimal pairs where only one of these features differs. For example, when we say the English words came and game, we know that the only difference between them is the voicing of the first consonant but this contrast is enough for them to be considered two different words. Place of articulation (PoA) is also contrastive. Game and dame both start with voiced stops, but one is velar and one is (usually) alveolar and this marks them as separate words. However, certain speakers pronounce dame with a dental stop (some Scottish accents, for example). As alveolar and dental stops are not contrastive in English, both would be considered acceptable variations of the same word. What this tells us is that not all contrasts are meaningful in all languages. We find the same situation when we look at contrastive units of sign languages.
PoA is contrastive in sign languages as well as in spoken languages. In sign languages PoAs are not places along the vocal tract but are various body parts where a sign takes place. These are called Locations. The same exact sign produced in two different Locations yields two different meanings. SEE and TELL in British Sign Language (BSL) are identical apart from their Location (from the eyes for SEE and from the lips for TELL) and this difference is what gives them separate meanings. Location is the first of five parameters that make up the phonology of signs.
The second parameter is Handshape. There are many possible handshapes and each sign language uses a certain sub-set of these as meaningful components of the language. Again, we can identify the handshapes used in a particular sign language by looking for minimal pairs. BSL, for example, has a contrast between a fist with the little finger raised (the [I] handshape) and a fist with the thumb raised (the [Ȧ] handshape). When we keep all other parameters the same and change just the handshape, two different signs are produced, for example PRAISE and CRITICISE. There are also handshapes that are contrastive in other languages but not contrastive in BSL. In American Sign Language there is a contrast between a fist made with the thumb over the fingers and a fist made with the fingers resting on the thumb. BSL does not have this distinction and use of either handshape for a sign such as EUROPE would not alter its meaning.
The orientation of the hand used in a sign is the third parameter. Orientation is the exact direction in which the handshape faces (upwards/downwards, leftwards/rightwards and towards/away from the signer). Even in gesture we can see how important hand orientation is, as we get a very different meaning if we turn the two-fingered peace sign around. In Britain this is offensive, yet this orientation may be seen as simply a variant of the same meaning in other cultures. Again, we can find minimal pairs in BSL where the only difference between signs is the orientation of the hand, for example NOW (in some varieties) and BRITISH (the former having the handshape oriented palm up and the latter palm down).
The fourth parameter in sign language phonology is Movement. This parameter concerns exactly how a handshape moves in a sign. LIVE and FEEL have the same location, handshape and orientation, but the movement (repeated up and down Movement or short upwards Movement) marks them as distinct signs.
The final parameter concerns the non-manual features (NMFs) of the sign. This parameter includes facial expressions and lip patterns. There are some signs that share the same Location, Handshape, Orientation and Movement and are only differentiated by NMFs. By including English mouthing alongside the sign, we can clarify whether a sign means GARAGE or GERMANY. As well as mouthing, there are facial expressions in sign languages that distinguish between signs. For example, the signs DEPRESSED and RELIEVED are differentiated only by the facial expression displaying these two emotions. There is also an NMF that marks negation (head shakes, mouth turns down and eyebrows raise and furrow). The sign MILK with the negation NMF becomes NO-MILK. At sentence level, NMFs can also turn a plain form into a question (through raising of the eyebrows and head tilt) so ALL-RIGHT can become the question form ALL-RIGHT?
These five parameters are the same across all sign languages and, like spoken language phonology, each sign language has restrictions on the way in which these parameters may combine. Certain combinations of these parameters are phonotactically illegal (for example, some Handshapes are not made in certain Orientations). Orfanidou et al (2009) found that when they presented BSL signers with phonotactically illegal nonsense signs, signers often used phonotactic knowledge to correct them. This suggests that native signers, like native speakers, have an underlying understanding of the phonotactics of their language.
Although phonology may at first seem about as far away as possible from the study of sign languages, I hope this post has shown that spoken language terminology and concepts can be successfully applied to another language modality. If you enjoy reading about sign linguistics, have a look at BSL QED’s short linguistics notes on BSL for more.
Sutton-Spence, R., & Woll, B. (1999). The linguistics of British Sign Language: An introduction. Cambridge: Cambridge University Press.
Orfanidou, E., Adam, R., McQueen, J. M., & Morgan, G. (2009). Making sense of nonsense in British Sign Language (BSL): The contribution of different phonological parameters to sign recognition. Memory & Cognition, 37(3), 302–15.
Edited18/03/15 to revise and clarify section on NMFs