Constructing Complexity in a Young Sign Language

Abstract

A universally acknowledged, core property of language is its complexity, at each level of structure - sounds, words, phrases, clauses, utterances, and higher levels of discourse. How does this complexity originate and develop in a language? We cannot fully answer this question from spoken languages, since they are all thousands of years old or descended from old languages. However, sign languages of deaf communities can arise at any time and provide empirical data for testing hypotheses related to the emergence of language complexity. An added advantage of the signed modality is a correspondence between visible physical articulations and linguistic structures, providing a more transparent view of linguistic complexity and its emergence (Sandler, 2012). These essential characteristics of sign languages allow us to address the issue of emerging complexity by documenting the use of the body for linguistic purposes. We look at three types of discourse relations of increasing complexity motivated by research on spoken languages - additive, symmetric, and asymmetric (Mann and Thompson, 1988; Sanders et al., 1992). Each relation type can connect units at two different levels: within propositions (simpler) and across propositions (more complex). We hypothesized that these relations provide a measure for charting the time course of emergence of complexity, from simplest to most complex, in a new sign language. We test this hypothesis on Israeli Sign Language (ISL), a young language, some of whose earliest users are still available for recording. Taking advantage of the unique relation in sign languages between bodily articulations and linguistic form, we study fifteen ISL signers from three generations, and demonstrate that the predictions indeed hold. We also find that younger signers tend to converge on more systematic marking of relations, that they use fewer articulators for a given linguistic function than older signers, and that the form of articulations becomes reduced, as the language matures. Mapping discourse relations to the bodily expression of linguistic components across age groups reveals how simpler, less constrained, and more gesture-like expressions, become language.

Keywords: compositionality; discourse relations; gesture; language complexity; language emergence; sign languages; use of body.

FIGURE 1

Typical intonational display of the antecedent clause of an ISL neutral conditional in a sentence meaning, “If you eat now, you won’t be hungry for lunch.” The image was captured while the signer was producing the underlined sign.

FIGURE 2

Typical intonational display of the antecedent clause of an ISL counterfactual conditional and its change in the consequence clause, in a sentence meaning, “If the goalkeeper had caught the ball, the team would have won the game” and glossed [GOALKEEPER HE CATCH-BALL] [WIN]. The figure shows the underlined signs.

FIGURE 3

Schema of complexity cline.

FIGURE 4

Percentage of intonational phrases containing each relation, displayed by age group.

FIGURE 5

Decrease in multiple marking of symmetric relations within propositions.

FIGURE 6

Variability of the marking of symmetric relations within proposition. Signer 1, 2, 8, and 15 showed no examples for this relation.

FIGURE 7

Marking of a symmetric relation by an older signer with opposite tilts of head and torso together. head and torso tilt left head and torso tilt right EXIST FOOD            NOT-EXIST FOOD Sometimes there was food and sometimes there wasn’t food (The underlined words in the glosses above are the words signed in the corresponding figures.).

FIGURE 8

Marking of a symmetric relation by a younger signer with opposite head-only tilts. head tilt right head tilt left BEFORE DOCTOR HE REPLACE            DIFFERENT NEW DOCTOR SHE SIGN GOOD

FIGURE 9

Marking of an asymmetric relation across propositions shown by an older signer – torso shift, forward head movement, head turn, and eyebrow raise accompanies the first part of this construction. torso and head turn, brow raise, head forward head tilt left FATHER SAY YOU TWO THREE            ME ONE GO My father said that if there had been two or three of us (girls), then I could have gone.

FIGURE 10

Marking of an asymmetric relation across propositions shown by a younger signer – forward head movement accompanies the first proposition When my mother needed urgent treatment and backward head movement accompanies the second proposition, we did not know what to do. head forward head back SHE MOTHER EMERGENCY PAST SHE            WE THINK WHAT-TO-DO When my mother needed urgent treatment we did not know what to do.

FIGURE 11

Mapping between simultaneous discourse relations and simultaneous articulations. Opposite torso tilts signal the symmetric contrast between the two major constituents (two different schooling situations); the non-dominant hand (=nd) marks topic continuity; and forward-backward head movement marks the asymmetric relation between dependent and matrix clauses within the first coordinated constituent. head forward    head back ____________  ______________________________________________________ torso tilt right                                       torso tilt left _____________________________________________________________________ _____________ [[ME GROW-UP SCHOOL THERE] [END SCHOOL THERE CLOSE DEAF INTEGRATE NO-MORE] [MOVE-HERE]] [[When I was at that school,] [they closed the deaf program]], [and I moved to another school.]]