A Grammar of Sign Language of the Netherlands (NGT)

Mouth gestures are articulated by the tongue and mouth, and are not related to words from a (surrounding) spoken language. There exists an overview of attested (phonetic) mouth gestures in NGT.

Some signs have a lexically specified mouth gesture with a disambiguating function. The two signs shown in Figure 2.33 are manually identical, whereas the mouth action differs: the sign funny in Figure 2.33a involves a mouth gesture in which the mouth is slightly opened and the signer breathes out; while in look_forward_to in Figure 2.33b, there is a mouthing corresponding to a Dutch word with the same meaning as the sign.

 

                                                           

                                   a. funny                                                              b. look_forward_to

Figure 2.33. Manually identical signs funny (a) and look_forward_to (b), which are disambiguated by accompanying mouth gesture vs. mouthing.

 

Furthermore, some signs are simply ill-formed without the accompanying mouth gesture. Examples of these are the signs be_present and suck_up shown in Figure 2.34.

 

                                                                                    

a. be_present	b. suck_up

 

Figure 2.34. Signs be_present (a) and suck_up (b), which involve obligatory mouth gestures (2.34a Crasborn et al. 2020, symbols added).

 

Most mouth gestures, such as the one in be_present, appear lexically with only one specific sign, but others appear with multiple signs. The mouth gesture ‘mouth open, tongue slackly hanging out’, which is present in suck_up above, also occurs with the signs not_succeed and throw_up, for instance.

A small, special category of mouth gestures concerns mouth gestures that occur on their own, without a manual component – and which could therefore be analyzed as non-manual lexemes, rather than sublexical elements. I am aware of two instances, which, strikingly, involve the same mouth gesture, but with two different meanings: cheat and menstrual_period. This mouth gesture – the tongue pushing against the inside of one of the cheeks (see Figure 2.35) – clearly is used to convey information that should be less visible to bystanders. 

 

 

 

Figure 2.35. Mouth gesture of tongue pushing against the inside of one of the cheeks.

 

 

 

According to Bank (2014), there is much variation in the use of mouth gestures both within individual signers and between signers. It is therefore likely that their role in the phonology is different from the other sublexical elements, as handshapes or movements, for instance, are not optional, while (most) mouth gestures seem to be. Lexicalized mouth gestures are therefore considered to be exceptional, as they are stored in the lexicon.