Sign language

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Two men and a woman signing American Sign Language (2008) ASL family.jpg
Two men and a woman signing American Sign Language (2008)
Preservation of the Sign Language, George W. Veditz (1913)

Sign languages (also known as signed languages) are languages that use the visual-manual modality to convey meaning, instead of spoken words. Sign languages are expressed through manual articulation in combination with non-manual markers. Sign languages are full-fledged natural languages with their own grammar and lexicon. [1] Sign languages are not universal and are usually not mutually intelligible, [2] although there are similarities among different sign languages.

Contents

Linguists consider both spoken and signed communication to be types of natural language, meaning that both emerged through an abstract, protracted aging process and evolved over time without meticulous planning. [3] This is supported by the fact that there is substantial overlap between the neural substrates of sign and spoken language processing, despite the obvious differences in modality. [4]

Sign language should not be confused with body language, a type of nonverbal communication. Linguists also distinguish natural sign languages from other systems that are precursors to them or obtained from them, such as constructed manual codes for spoken languages, home sign, "baby sign", and signs learned by non-human primates.

Wherever communities of deaf people exist, sign languages have developed as useful means of communication and form the core of local deaf cultures. Although signing is used primarily by the deaf and hard of hearing, it is also used by hearing individuals, such as those unable to physically speak, those who have trouble with oral language due to a disability or condition (augmentative and alternative communication), and those with deaf family members including children of deaf adults.

The number of sign languages worldwide is not precisely known. Each country generally has its own native sign language; some have more than one. The 2021 edition of Ethnologue lists 150 sign languages, [5] while the SIGN-HUB Atlas of Sign Language Structures lists over 200 and notes that there are more that have not been documented or discovered yet. [6] As of 2021, Indo-Pakistani Sign Language is the most-used sign language in the world, and Ethnologue ranks it as the 151st most "spoken" language in the world. [7]

Some sign languages have obtained some form of legal recognition. [8]

History

Juan Pablo Bonet, Reduccion de las letras y arte para ensenar a hablar a los mudos
("Reduction of letters and art for teaching mute people to speak") (Madrid, 1620) Arte para ensenar a hablar a los mudos.jpg
Juan Pablo Bonet, Reducción de las letras y arte para enseñar a hablar a los mudos ("Reduction of letters and art for teaching mute people to speak") (Madrid, 1620)

Groups of deaf people have used sign languages throughout history. One of the earliest written records of a sign language is from the fifth century BC, in Plato's Cratylus , where Socrates says: "If we hadn't a voice or a tongue, and wanted to express things to one another, wouldn't we try to make signs by moving our hands, head, and the rest of our body, just as dumb people do at present?" [9] Most of what is known about pre-19th-century sign languages is limited to the manual alphabets (fingerspelling systems) that were invented to facilitate the transfer of words from a spoken language to a sign language, rather than documentation of the language itself.

Debate around European monastic sign languages developed in the Middle Ages has come to regard them as gestural systems rather than true sign languages. [10] Monastic sign languages were the basis for the first known manual alphabet used in deaf schools, developed by Pedro Ponce de León. [11]

Ghanaian Sign Language alphabet

The earliest records of contact between Europeans and Indigenous peoples of the Gulf Coast region in what is now Texas and northern Mexico note a fully formed sign language already in use by the time of the Europeans' arrival there. [12] These records include the accounts of Cabeza de Vaca in 1527 and Coronado in 1541.

In 1620, Juan Pablo Bonet published Reducción de las letras y arte para enseñar a hablar a los mudos ('Reduction of letters and art for teaching mute people to speak') in Madrid. [13] It is considered the first modern treatise of sign language phonetics, setting out a method of oral education for deaf people and a manual alphabet.

Chirogram from Chirologia, 1644 Jbulwer.jpg
Chirogram from Chirologia, 1644

In Britain, manual alphabets were also in use for a number of purposes, such as secret communication, [14] public speaking, or communication by or with deaf people. [15] In 1648, John Bulwer described "Master Babington", a deaf man proficient in the use of a manual alphabet, "contryved on the joynts of his fingers", whose wife could converse with him easily, even in the dark through the use of tactile signing. [16]

In 1680, George Dalgarno published Didascalocophus, or, The deaf and dumb mans tutor, [17] in which he presented his own method of deaf education, including an "arthrological" alphabet, where letters are indicated by pointing to different joints of the fingers and palm of the left hand. Arthrological systems had been in use by hearing people for some time; [18] some have speculated that they can be traced to early Ogham manual alphabets. [19] [20]

The vowels of this alphabet have survived in the modern alphabets used in British Sign Language, Auslan and New Zealand Sign Language. The earliest known printed pictures of consonants of the modern two-handed alphabet appeared in 1698 with Digiti Lingua (Latin for Language [or Tongue] of the Finger), a pamphlet by an anonymous author who was himself unable to speak. [21] [22] He suggested that the manual alphabet could also be used by mutes, for silence and secrecy, or purely for entertainment. Nine of its letters can be traced to earlier alphabets, and 17 letters of the modern two-handed alphabet can be found among the two sets of 26 handshapes depicted.

Charles de La Fin published a book in 1692 describing an alphabetic system where pointing to a body part represented the first letter of the part (e.g. Brow=B), and vowels were located on the fingertips as with the other British systems. [23] He described such codes for both English and Latin.

By 1720, the British manual alphabet had found more or less its present form. [24] Descendants of this alphabet have been used by deaf communities, at least in education, in the former British colonies India, Australia, New Zealand, Uganda and South Africa, as well as the republics and provinces of the former Yugoslavia, Grand Cayman Island in the Caribbean, Indonesia, Norway, Germany and the United States.

During the Polygar Wars against the British, Veeran Sundaralingam communicated with Veerapandiya Kattabomman's mute younger brother, Oomaithurai, by using their own sign language.[ clarification needed ]

Frenchman Charles-Michel de l'Épée published his manual alphabet in the 18th century, which has survived largely unchanged in France and North America until the present time. In 1755, Abbé de l'Épée founded the first school for deaf children in Paris; Laurent Clerc was arguably its most famous graduate. Clerc went to the United States with Thomas Hopkins Gallaudet to found the American School for the Deaf in Hartford, Connecticut, in 1817. [25] [26] Gallaudet's son, Edward Miner Gallaudet, founded a school for the deaf in 1857 in Washington, D.C., which in 1864 became the National Deaf-Mute College. Now called Gallaudet University, it is still the only liberal arts university for deaf people in the world.

International Sign, formerly known as Gestuno, is used mainly at international deaf events such as the Deaflympics and meetings of the World Federation of the Deaf. While recent studies claim that International Sign is a kind of a pidgin, they conclude that it is more complex than a typical pidgin and indeed is more like a full sign language. [27] [28] While the more commonly used term is International Sign, it is sometimes referred to as Gestuno, [29] International Sign Pidgin [28] or International Gesture (IG). [30] International Sign is a term used by the World Federation of the Deaf and other international organisations.

Linguistics

Sign languages have capability and complexity equal to spoken languages; their study as part of the field of linguistics has demonstrated that they exhibit the fundamental properties that exist in all languages. [31] [1] [32] Such fundamental properties include duality of patterning [33] and recursion. [34] Duality of patterning means that languages are composed of smaller, meaningless units which can be combined into larger units with meaning (see below). The term recursion means that languages exhibit grammatical rules and the output of such a rule can be the input of the same rule. It is, for example, possible in sign languages to create subordinate clauses and a subordinate clause may contain another subordinate clause.

Sign languages are not mime—in other words, signs are conventional, often arbitrary and do not necessarily have a visual relationship to their referent, much as most spoken language is not onomatopoeic. While iconicity is more systematic and widespread in sign languages than in spoken ones, the difference is not categorical. [35] The visual modality allows the human preference for close connections between form and meaning, to be more fully expresse, whereasdthis is more suppressed in spoken language., [36]

Sign languages, like spoken languages, organize elementary, meaningless units into meaningful semantic units. This type of organization in natural language is often called duality of patterning. As in spoken languages, these meaningless units are represented as (combinations of) features, although coarser descriptions are often also made in terms of five "parameters": handshape (or handform), orientation, location (or place of articulation), movement, and non-manual expression. These meaningless units in sign languages were initially called cheremes, [37] from the Greek word for hand, by analogy to the phonemes, from Greek for voice, of spoken languages. Now they are sometimes called phonemes when describing sign languages too, since the function is essentially the same, but more commonly discussed in terms of "features" [1] or "parameters". [38] More generally, both sign and spoken languages share the characteristics that linguists have found in all natural human languages, such as transitoriness, semanticity, arbitrariness, productivity, and cultural transmission.[ clarification needed ]

Common linguistic features of many sign languages are the occurrence of classifier constructions, a high degree of inflection by means of changes of movement, and a topic-comment syntax. More than spoken languages, sign languages can convey meaning by simultaneous means, e.g. by the use of space, two manual articulators, and the signer's face and body. Though there is still much discussion on the topic of iconicity in sign languages, classifiers are generally considered to be highly iconic, as these complex constructions "function as predicates that may express any or all of the following: motion, position, stative-descriptive, or handling information". [39] The term classifier is not used by everyone working on these constructions. Across the field of sign language linguistics the same constructions are also referred with other terms such as depictive signs.[ citation needed ]

Today, linguists study sign languages as true languages, part of the field of linguistics. However, the category "sign languages" was not added to the Linguistic Bibliography/Bibliographie Linguistique until the 1988 volume, [40] when it appeared with 39 entries.

Relationships with spoken languages

Sign language relief sculpture on a stone wall: "Life is beautiful, be happy and love each other", by Czech sculptor Zuzana Cizkova on Holeckova Street in Prague-Smichov, by a school for the deaf Holeckova, napis ve znakove reci.jpg
Sign language relief sculpture on a stone wall: "Life is beautiful, be happy and love each other", by Czech sculptor Zuzana Čížková on Holečkova Street in Prague-Smíchov, by a school for the deaf

There is a common misconception [41] that sign languages are spoken language expressed in signs, or that they were invented by hearing people. [42] Similarities in language processing in the brain between signed and spoken languages further perpetuated this misconception. Hearing teachers in deaf schools, such as Charles-Michel de l'Épée or Thomas Hopkins Gallaudet, are often incorrectly referred to as "inventors" of sign language. Instead, sign languages, like all natural languages, are developed by the people who use them, in this case, deaf people, who may have little or no knowledge of any spoken language.

As a sign language develops, it sometimes borrows elements from spoken languages, just as all languages borrow from other languages that they are in contact with. Sign languages vary in how much they borrow from spoken languages. In many sign languages, a manual alphabet ("fingerspelling") may be used in signed communication to borrow a word from a spoken language. This is most commonly used for proper names of people and places; it is also used in some languages for concepts for which no sign is available at that moment, particularly if the people involved are to some extent bilingual in the spoken language. Fingerspelling can sometimes be a source of new signs, such as initialized signs, in which the handshape represents the first letter of a spoken word with the same meaning.

A January 2021 Welsh Government video informing viewers of their new COVID-19 regulations

On the whole, though, sign languages are independent of spoken languages and follow their own paths of development. For example, British Sign Language (BSL) and American Sign Language (ASL) are quite different and mutually unintelligible, even though the hearing people of the United Kingdom and the United States share the same spoken language. The grammars of sign languages do not usually resemble those of spoken languages used in the same geographical area; in fact, in terms of syntax, ASL shares more with spoken Japanese than it does with English. [43]

Similarly, countries which use a single spoken language throughout may have two or more sign languages, or an area that contains more than one spoken language might use only one sign language. South Africa, which has 11 official spoken languages and a similar number of other widely used spoken languages, is a good example of this. It has only one sign language with two variants due to its history of having two major educational institutions for the deaf which have served different geographic areas of the country.

Spatial grammar and simultaneity

Hello in ASL (American Sign Language)
Another variation of hello in ASL (American Sign Language)

Sign languages exploit the unique features of the visual medium (sight), but may also exploit tactile features (tactile sign languages). Spoken language is by and large linear; only one sound can be made or received at a time. Sign language, on the other hand, is visual and, hence, can use a simultaneous expression, although this is limited articulatorily and linguistically. Visual perception allows processing of simultaneous information.

One way in which many sign languages take advantage of the spatial nature of the language is through the use of classifiers. Classifiers allow a signer to spatially show a referent's type, size, shape, movement, or extent.

The possible simultaneity of sign languages in contrast to spoken languages is sometimes exaggerated. The use of two manual articulators is subject to motor constraints, resulting in a large extent of symmetry [44] or signing with one articulator only. Further, sign languages, just like spoken languages, depend on linear sequencing of signs to form sentences; the greater use of simultaneity is mostly seen in the morphology (internal structure of individual signs).

Non-manual elements

Sign languages convey much of their prosody through non-manual elements. Postures or movements of the body, head, eyebrows, eyes, cheeks, and mouth are used in various combinations to show several categories of information, including lexical distinction, grammatical structure, adjectival or adverbial content, and discourse functions.

At the lexical level, signs can be lexically specified for non-manual elements in addition to the manual articulation. For instance, facial expressions may accompany verbs of emotion, as in the sign for angry in Czech Sign Language. Non-manual elements may also be lexically contrastive. For example, in ASL (American Sign Language), facial components distinguish some signs from other signs. An example is the sign translated as not yet, which requires that the tongue touch the lower lip and that the head rotate from side to side, in addition to the manual part of the sign. Without these features the sign would be interpreted as late. [45] Mouthings, which are (parts of) spoken words accompanying lexical signs, can also be contrastive, as in the manually identical signs for doctor and battery in Sign Language of the Netherlands. [46]

While the content of a signed sentence is produced manually, many grammatical functions are produced non-manually (i.e., with the face and the torso). [47] Such functions include questions, negation, relative clauses and topicalization. [48] ASL and BSL use similar non-manual marking for yes/no questions, for example. They are shown through raised eyebrows and a forward head tilt. [49] [50]

Some adjectival and adverbial information is conveyed through non-manual elements, but what these elements are varies from language to language. For instance, in ASL a slightly open mouth with the tongue relaxed and visible in the corner of the mouth means "carelessly", but a similar non-manual in BSL means "boring" or "unpleasant". [50]

Discourse functions such as turn taking are largely regulated through head movement and eye gaze. Since the addressee in a signed conversation must be watching the signer, a signer can avoid letting the other person have a turn by not looking at them, or can indicate that the other person may have a turn by making eye contact. [51]

Iconicity

Iconicity is similarity or analogy between the form of a sign (linguistic or otherwise) and its meaning, as opposed to arbitrariness. [52] The first studies on iconicity in ASL were published in the late 1970s and early 1980s. Many early sign language linguists rejected the notion that iconicity was an important aspect of sign languages, considering most perceived iconicity to be extralinguistic. [53] [31] However, mimetic aspects of sign language (signs that imitate, mimic, or represent) are found in abundance across a wide variety of sign languages. For example, when deaf children learning sign language try to express something but do not know the associated sign, they will often invent an iconic sign that displays mimetic properties. [54] Though it never disappears from a particular sign language, iconicity is gradually weakened as forms of sign languages become more customary and are subsequently grammaticized. As a form becomes more conventional, it becomes disseminated in a methodical way phonologically to the rest of the sign language community. [55] Nancy Frishberg concluded that though originally present in many signs, iconicity is degraded over time through the application of natural grammatical processes. [53]

In 1978, psychologist Roger Brown was one of the first to suggest that the properties of ASL give it a clear advantage in terms of learning and memory. [56] In his study, Brown found that when a group of six hearing children were taught signs that had high levels of iconic mapping they were significantly more likely to recall the signs in a later memory task than another group of six children that were taught signs that had little or no iconic properties. In contrast to Brown, linguists Elissa Newport and Richard Meier found that iconicity "appears to have virtually no impact on the acquisition of American Sign Language". [57]

A central task for the pioneers of sign language linguistics was trying to prove that ASL was a real language and not merely a collection of gestures or "English on the hands." One of the prevailing beliefs at this time was that "real languages" must consist of an arbitrary relationship between form and meaning. Thus, if ASL consisted of signs that had iconic form-meaning relationship, it could not be considered a real language. As a result, iconicity as a whole was largely neglected in research of sign languages for a long time. However, iconicity also plays a role in many spoken languages. Spoken Japanese for example exhibits many words mimicking the sounds of their potential referents (see Japanese sound symbolism). Later researchers, thus, acknowledged that natural languages do not need to consist of an arbitrary relationship between form and meaning. [58] The visual nature of sign language simply allows for a greater degree of iconicity compared to spoken languages as most real-world objects can be described by a prototypical shape (e.g., a table usually has a flat surface), but most real-world objects do not make prototypical sounds that can be mimicked by spoken languages (e.g., tables do not make prototypical sounds). However, sign languages are not fully iconic. On the one hand, there are also many arbitrary signs in sign languages and, on the other hand, the grammar of a sign language puts limits to the degree of iconicity: All known sign languages, for example, express lexical concepts via manual signs. From a truly iconic language one would expect that a concept like smiling would be expressed by mimicking a smile (i.e., by performing a smiling face). All known sign languages, however, do not express the concept of smiling by a smiling face, but by a manual sign. [59]

The cognitive linguistics perspective rejects a more traditional definition of iconicity as a relationship between linguistic form and a concrete, real-world referent. Rather it is a set of selected correspondences between the form and meaning of a sign. [36] In this view, iconicity is grounded in a language user's mental representation ("construal" in cognitive grammar). It is defined as a fully grammatical and central aspect of a sign language rather than a peripheral phenomenon. [60]

The cognitive linguistics perspective allows for some signs to be fully iconic or partially iconic given the number of correspondences between the possible parameters of form and meaning. [61] In this way, the Israeli Sign Language (ISL) sign for ask has parts of its form that are iconic ("movement away from the mouth" means "something coming from the mouth"), and parts that are arbitrary (the handshape, and the orientation). [62]

Many signs have metaphoric mappings as well as iconic or metonymic ones. For these signs there are three-way correspondences between a form, a concrete source and an abstract target meaning. The ASL sign LEARN has this three-way correspondence. The abstract target meaning is "learning". The concrete source is putting objects into the head from books. The form is a grasping hand moving from an open palm to the forehead. The iconic correspondence is between form and concrete source. The metaphorical correspondence is between concrete source and abstract target meaning. Because the concrete source is connected to two correspondences linguistics refer to metaphorical signs as "double mapped". [36] [61] [62]

Classification

The classification of Sign Language families
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French Sign Language family
-American Sign Language (ASL) cluster
-Russian Sign Language cluster
-Czech Sign Language cluster
Danish Sign Language family
Swedish Sign Language family
German Sign Language family
Vietnamese sign languages & some Thai and Lao SLs
Arab sign-language family
Indo-Pakistani Sign Language
Chinese Sign Language
Japanese Sign Language family
BANZSL family (British, Australian and New Zealand Sign Language)
South African Sign Language (within the BANZSL family)
Isolated languages
No data Sign language families.svg
The classification of Sign Language families
  American Sign Language (ASL) cluster
  Russian Sign Language cluster
  Czech Sign Language cluster
   Vietnamese sign languages & some Thai and Lao SLs
   BANZSL family (British, Australian and New Zealand Sign Language)
   South African Sign Language (within the BANZSL family)
  Isolated languages
  No data

Sign languages may be classified by how they arise.

In non-signing communities, home sign is not a full language, but closer to a pidgin. Home sign is amorphous and generally idiosyncratic to a particular family, where a deaf child does not have contact with other deaf children and is not educated in sign. Such systems are not generally passed on from one generation to the next. Where they are passed on, creolization would be expected to occur, resulting in a full language. However, home sign may also be closer to full language in communities where the hearing population has a gestural mode of language; examples include various Australian Aboriginal sign languages and gestural systems across West Africa, such as Mofu-Gudur in Cameroon.

A village sign language is a local indigenous language that typically arises over several generations in a relatively insular community with a high incidence of deafness, and is used both by the deaf and by a significant portion of the hearing community, who have deaf family and friends. [63] The most famous of these is probably the extinct Martha's Vineyard Sign Language of the U.S., but there are also numerous village languages scattered throughout Africa, Asia, and America.

Deaf-community sign languages, on the other hand, arise where deaf people come together to form their own communities. These include school sign, such as Nicaraguan Sign Language, which develop in the student bodies of deaf schools which do not use sign as a language of instruction, as well as community languages such as Bamako Sign Language, which arise where generally uneducated deaf people congregate in urban centers for employment. At first, Deaf-community sign languages are not generally known by the hearing population, in many cases not even by close family members. However, they may grow, in some cases becoming a language of instruction and receiving official recognition, as in the case of ASL.

Both contrast with speech-taboo languages such as the various Aboriginal Australian sign languages, which are developed by the hearing community and only used secondarily by the deaf. It is doubtful whether most of these are languages in their own right, rather than manual codes of spoken languages, though a few such as Yolngu Sign Language are independent of any particular spoken language. Hearing people may also develop sign to communicate with users of other languages, as in Plains Indian Sign Language; this was a contact signing system or pidgin that was evidently not used by deaf people in the Plains nations, though it presumably influenced home sign.

Language contact and creolization is common in the development of sign languages, making clear family classifications difficult– it is often unclear whether lexical similarity is due to borrowing or a common parent language, or whether there was one or several parent languages, such as several village languages merging into a Deaf-community language. Contact occurs between sign languages, between sign and spoken languages (contact sign, a kind of pidgin), and between sign languages and gestural systems used by the broader community. For example, Adamorobe Sign Language, a village sign language of Ghana, may be related to the "gestural trade jargon used in the markets throughout West Africa", in vocabulary and areal features including prosody and phonetics. [64] [65]

Young students learn some words of Lao sign language from Suliphone, a deaf artist. This was one of several activities at a school book party sponsored by Big Brother Mouse, a literacy project in Laos where Suliphone works. Lao sign language 025.jpg
Young students learn some words of Lao sign language from Suliphone, a deaf artist. This was one of several activities at a school book party sponsored by Big Brother Mouse, a literacy project in Laos where Suliphone works.

The only comprehensive classification along these lines going beyond a simple listing of languages dates back to 1991. [74] The classification is based on the 69 sign languages from the 1988 edition of Ethnologue that were known at the time of the 1989 conference on sign languages in Montreal and 11 more languages the author added after the conference. [76]

Wittmann classification of sign languages
Primary
language
Primary
group
Auxiliary
language
Auxiliary
group
Prototype-A [77] 5172
Prototype-R [78] 1811
BSL-derived 8
DGS-derived 1 or 2
JSL-derived 2

LSF-derived 30
LSG-derived

1?

In his classification, the author distinguishes between primary and auxiliary sign languages [79] as well as between single languages and names that are thought to refer to more than one language. [80] The prototype-A class of languages includes all those sign languages that seemingly cannot be derived from any other language. [77] Prototype-R languages are languages that are remotely modelled on a prototype-A language (in many cases thought to have been French Sign Language) by a process Kroeber (1940) called "stimulus diffusion". [78] The families of BSL, DGS, JSL, LSF (and possibly LSG) were the products of creolization and relexification of prototype languages. [81] Creolization is seen as enriching overt morphology in sign languages, as compared to reducing overt morphology in spoken languages. [82]

Typology

Linguistic typology (going back to Edward Sapir) is based on word structure and distinguishes morphological classes such as agglutinating/concatenating, inflectional, polysynthetic, incorporating, and isolating ones.

Sign languages vary in word-order typology. For example, Austrian Sign Language, Japanese Sign Language and Indo-Pakistani Sign Language are Subject-object-verb while ASL is Subject-verb-object. Influence from the surrounding spoken languages is not improbable.

Sign languages tend to be incorporating classifier languages, where a classifier handshape representing the object is incorporated into those transitive verbs which allow such modification. For a similar group of intransitive verbs (especially motion verbs), it is the subject which is incorporated. Only in a very few sign languages (for instance Japanese Sign Language) are agents ever incorporated. In this way, since subjects of intransitives are treated similarly to objects of transitives, incorporation in sign languages can be said to follow an ergative pattern.

Brentari [83] [84] classifies sign languages as a whole group determined by the medium of communication (visual instead of auditory) as one group with the features monosyllabic and polymorphemic. That means, that one syllable (i.e. one word, one sign) can express several morphemes, e.g., subject and object of a verb determine the direction of the verb's movement (inflection).

Another aspect of typology that has been studied in sign languages is their systems for cardinal numbers. [85] Typologically significant differences have been found between sign languages.

Acquisition

Children who are exposed to a sign language from birth will acquire it, just as hearing children acquire their native spoken language. [86] In a study done at McGill University, they found that American Sign Language users who acquired the language natively (from birth) performed better when asked to copy videos of ASL sentences than ASL users who acquired the language later in life. They also found that there are differences in the grammatical morphology of ASL sentences between the two groups, all suggesting that there is a very important critical period in learning signed languages. [87]

The acquisition of non-manual features follows an interesting pattern: When a word that always has a particular non-manual feature associated with it (such as a wh-question word) is learned, the non-manual aspects are attached to the word but do not have the flexibility associated with adult use. At a certain point, the non-manual features are dropped and the word is produced with no facial expression. After a few months, the non-manuals reappear, this time being used the way adult signers would use them. [88]

Written forms

Sign languages do not have a traditional or formal written form. Many deaf people do not see a need to write their own language. [89]

Several ways to represent sign languages in written form have been developed.

So far, there is no consensus regarding the written form of sign language. Except for SignWriting, none are widely used. Maria Galea writes that SignWriting "is becoming widespread, uncontainable and untraceable. In the same way that works written in and about a well developed writing system such as the Latin script, the time has arrived where SW is so widespread, that it is impossible in the same way to list all works that have been produced using this writing system and that have been written about this writing system." [95] In 2015, the Federal University of Santa Catarina accepted a dissertation written in Brazilian Sign Language using Sutton SignWriting for a master's degree in linguistics. The dissertation "The Writing of Grammatical Non-Manual Expressions in Sentences in LIBRAS Using the SignWriting System" by João Paulo Ampessan states that "the data indicate the need for [non-manual expressions] usage in writing sign language". [96]

Sign perception

For a native signer, sign perception influences how the mind makes sense of their visual language experience. For example, a handshape may vary based on the other signs made before or after it, but these variations are arranged in perceptual categories during its development. The mind detects handshape contrasts but groups similar handshapes together in one category. [97] [98] [99] Different handshapes are stored in other categories. The mind ignores some of the similarities between different perceptual categories, at the same time preserving the visual information within each perceptual category of handshape variation.

In society

Deaf communities and Deaf culture

When deaf people constitute a relatively small proportion of the general population, deaf communities often develop that are distinct from the surrounding hearing community. [100] These deaf communities are very widespread in the world, associated especially with sign languages used in urban areas and throughout a nation, and the cultures they have developed are very rich.

One example of sign language variation in the deaf community is Black ASL. This sign language was developed in the black deaf community as a variant during the American era of segregation and racism, where young black deaf students were forced to attend separate schools than their white deaf peers. [101]

Use of sign languages in hearing communities

On occasion, where the prevalence of deaf people is high enough, a deaf sign language has been taken up by an entire local community, forming what is sometimes called a "village sign language" [102] or "shared signing community". [103] Typically this happens in small, tightly integrated communities with a closed gene pool. Famous examples include:

In such communities deaf people are generally well-integrated in the general community and not socially disadvantaged, so much so that it is difficult to speak of a separate "Deaf" community. [100]

Many Australian Aboriginal sign languages arose in a context of extensive speech taboos, such as during mourning and initiation rites. They are or were especially highly developed among the Warlpiri, Warumungu, Dieri, Kaytetye, Arrernte, and Warlmanpa, and are based on their respective spoken languages.

A sign language arose among tribes of American Indians in the Great Plains region of North America (see Plains Indian Sign Language) before European contact. It was used by hearing people to communicate among tribes with different spoken languages, as well as by deaf people. There are especially users today among the Crow, Cheyenne, and Arapaho.

Sign language is also used as a form of alternative or augmentative communication by people who can hear but have difficulties using their voices to speak. [104]

Increasingly, hearing schools and universities are expressing interest in incorporating sign language. In the U.S., enrollment for ASL (American Sign Language) classes as part of students' choice of second language is on the rise. [105] In New Zealand, one year after the passing of NZSL Act 2006 in parliament, a NZSL curriculum was released for schools to take NZSL as an optional subject. The curriculum and teaching materials were designed to target intermediate schools from Years 7 to 10, (NZ Herald, 2007).

Some sign languages have obtained some form of legal recognition, while others have no status at all. Sarah Batterbury has argued that sign languages should be recognized and supported not merely as an accommodation for those with disabilities, but as the communication medium of language communities. [106]

Legal requirements covering sign language accessibility in media vary from country to country. In the United Kingdom, the Broadcasting Act 1996 addressed the requirements for blind and deaf viewers, [107] but has since been replaced by the Communications Act 2003.

Interpretation

A Polish Sign Language interpreter at the Przystanek Woodstock in 2017 2017 Woodstock 022 Jezyk migowy.jpg
A Polish Sign Language interpreter at the Przystanek Woodstock in 2017

In order to facilitate communication between deaf and hearing people, sign language interpreters are often used. Such activities involve considerable effort on the part of the interpreter, since sign languages are distinct natural languages with their own syntax, different from any spoken language.

The interpretation flow is normally between a sign language and a spoken language that are customarily used in the same country, such as French Sign Language (LSF) and spoken French in France, Spanish Sign Language (LSE) to spoken Spanish in Spain, British Sign Language (BSL) and spoken English in the U.K., and American Sign Language (ASL) and spoken English in the U.S. and most of anglophone Canada (since BSL and ASL are distinct sign languages both used in English-speaking countries), etc. Sign language interpreters who can translate between signed and spoken languages that are not normally paired (such as between LSE and English), are also available, albeit less frequently.

Video about access to cultural institutions in Mexico, with Mexican Sign Language interpretation and captions in Spanish

Sign language is sometimes provided for television programmes that include speech. The signer usually appears in the bottom corner of the screen, with the programme being broadcast full size or slightly shrunk away from that corner. Typically for press conferences such as those given by the Mayor of New York City, the signer appears to stage left or right of the public official to allow both the speaker and signer to be in frame at the same time. Live sign interpretation of important televised events is increasingly common but still an informal industry [108] In traditional analogue broadcasting, some programmes are repeated outside main viewing hours with a signer present. [109] Some emerging television technologies allow the viewer to turn the signer on and off in a similar manner to subtitles and closed captioning. [109]

Technology

A deaf person using a remote VRS interpreter to communicate with a hearing person Deaf or HoH person at his workplace using a Video Relay Service to communicate with a hearing person via a Video Interpreter and sign language SVCC 2007 Brigitte SLI + Mark.jpg
A deaf person using a remote VRS interpreter to communicate with a hearing person

One of the first demonstrations of the ability for telecommunications to help sign language users communicate with each other occurred when AT&T's videophone (trademarked as the Picturephone) was introduced to the public at the 1964 New York World's Fair– two deaf users were able to freely communicate with each other between the fair and another city. [110] However, video communication did not become widely available until sufficient bandwidth for the high volume of video data became available in the early 2000s.

The Internet now allows deaf people to talk via a video link, either with a special-purpose videophone designed for use with sign language or with "off-the-shelf" video services designed for use with broadband and an ordinary computer webcam. The special videophones that are designed for sign language communication may provide better quality than 'off-the-shelf' services and may use data compression methods specifically designed to maximize the intelligibility of sign languages. Some advanced equipment enables a person to remotely control the other person's video camera, in order to zoom in and out or to point the camera better to understand the signing.

Video interpreter sign used at VRS/VRI service locations Video interpreter.svg
Video interpreter sign used at VRS/VRI service locations

Interpreters may be physically present with both parties to the conversation but, since the technological advancements in the early 2000s, provision of interpreters in remote locations has become available. In video remote interpreting (VRI), the two clients (a sign language user and a hearing person who wish to communicate with each other) are in one location, and the interpreter is in another. The interpreter communicates with the sign language user via a video telecommunications link, and with the hearing person by an audio link. VRI can be used for situations in which no on-site interpreters are available.

However, VRI cannot be used for situations in which all parties are speaking via telephone alone. With video relay service (VRS), the sign language user, the interpreter, and the hearing person are in three separate locations, thus allowing the two clients to talk to each other on the phone through the interpreter.

With recent developments in artificial intelligence in computer science, some recent deep learning based machine translation algorithms have been developed which automatically translate short videos containing sign language directly to written language. [111]

Sign language has been incorporated into film; for example, all movies shown in Brazilian movie theaters must have a Brazilian Sign Language video track available to play alongside the film via a second screen. [112] [113]

Sign Union flag

The Sign Union flag Sign Union flag.svg
The Sign Union flag

The Sign Union flag was designed by Arnaud Balard. After studying flags around the world and vexillology principles for two years, Balard revealed the design of the flag, featuring the stylized outline of a hand. The three colors which make up the flag design are representative of Deafhood and humanity (dark blue), sign language (turquoise), and enlightenment and hope (yellow). Balard intended the flag to be an international symbol which welcomes deaf people. [114]

Language endangerment and extinction

As with any spoken language, sign languages are also vulnerable to becoming endangered. [115] For example, a sign language used by a small community may be endangered and even abandoned as users shift to a sign language used by a larger community, as has happened with Hawai'i Sign Language, which is almost extinct except for a few elderly signers. [116] [117] Even nationally recognised sign languages can be endangered; for example, New Zealand Sign Language is losing users. [118] Methods are being developed to assess the language vitality of sign languages. [119]

Communication systems similar to sign language

There are a number of communication systems that are similar in some respects to sign languages, while not having all the characteristics of a full sign language, particularly its grammatical structure. Many of these are either precursors to natural sign languages or are derived from them.

Manual codes for spoken languages

When Deaf and Hearing people interact, signing systems may be developed that use signs drawn from a natural sign language but used according to the grammar of the spoken language. In particular, when people devise one-for-one sign-for-word correspondences between spoken words (or even morphemes) and signs that represent them, the system that results is a manual code for a spoken language, rather than a natural sign language. Such systems may be invented in an attempt to help teach Deaf children the spoken language, and generally are not used outside an educational context.

"Baby sign language" with hearing children

Some hearing parents teach signs to young hearing children. Since the muscles in babies' hands grow and develop quicker than their mouths, signs are seen as a beneficial option for better communication. [124] Babies can usually produce signs before they can speak.[ citation needed ] This reduces the confusion between parents when trying to figure out what their child wants. When the child begins to speak, signing is usually abandoned, so the child does not progress to acquiring the grammar of the sign language. [125]

This is in contrast to hearing children who grow up with Deaf parents, who generally acquire the full sign language natively, the same as Deaf children of Deaf parents.

Home sign

Informal, rudimentary sign systems are sometimes developed within a single family. For instance, when hearing parents with no sign language skills have a deaf child, the child may develop a system of signs naturally, unless repressed by the parents. The term for these mini-languages is home sign (sometimes "kitchen sign"). [126]

Home sign arises due to the absence of any other way to communicate. Within the span of a single lifetime and without the support or feedback of a community, the child naturally invents signs to help meet his or her communication needs, and may even develop a few grammatical rules for combining short sequences of signs. Still, this kind of system is inadequate for the intellectual development of a child and it comes nowhere near meeting the standards linguists use to describe a complete language. No type of home sign is recognized as a full language. [127]

Primate use

There have been several notable examples of scientists teaching signs to non-human primates in order to communicate with humans, [128] such as chimpanzees, [129] [130] [131] [132] [133] [134] [135] gorillas [136] and orangutans. [137] However, linguists generally point out that this does not constitute knowledge of a human language as a complete system, rather than simply signs/words. [138] [139] [140] [141] [142] Notable examples of animals who have learned signs include:

Gestural theory of human language origins

One theory of the evolution of human language states that it developed first as a gestural system, which later shifted to speech. [143] [144] [145] [146] [65] [147] An important question for this gestural theory is what caused the shift to vocalization. [148] [149] [150]

See also

Related Research Articles

<span class="mw-page-title-main">American Sign Language</span> Sign language used predominantly in the US

American Sign Language (ASL) is a natural language that serves as the predominant sign language of Deaf communities in the United States and most of Anglophone Canada. ASL is a complete and organized visual language that is expressed by employing both manual and nonmanual features. Besides North America, dialects of ASL and ASL-based creoles are used in many countries around the world, including much of West Africa and parts of Southeast Asia. ASL is also widely learned as a second language, serving as a lingua franca. ASL is most closely related to French Sign Language (LSF). It has been proposed that ASL is a creole language of LSF, although ASL shows features atypical of creole languages, such as agglutinative morphology.

<span class="mw-page-title-main">Fingerspelling</span> Form of communication using one or both hands

Fingerspelling is the representation of the letters of a writing system, and sometimes numeral systems, using only the hands. These manual alphabets have often been used in deaf education and have subsequently been adopted as a distinct part of a number of sign languages. There are about forty manual alphabets around the world. Historically, manual alphabets have had a number of additional applications—including use as ciphers, as mnemonics and in silent religious settings.

<span class="mw-page-title-main">International Sign</span> Sign language, used particularly at international meetings

International Sign (IS) is a pidgin sign language which is used in a variety of different contexts, particularly as an international auxiliary language at meetings such as the World Federation of the Deaf (WFD) congress, in some European Union settings, and at some UN conferences, at events such as the Deaflympics, the Miss & Mister Deaf World, and Eurovision, and informally when travelling and socialising.

<span class="mw-page-title-main">British Sign Language</span> Sign language used in the United Kingdom

British Sign Language (BSL) is a sign language used in the United Kingdom and is the first or preferred language among the deaf community in the UK. While private correspondence from William Stokoe hinted at a formal name for the language in 1960, the first usage of the term "British Sign Language" in an academic publication was likely by Aaron Cicourel. Based on the percentage of people who reported 'using British Sign Language at home' on the 2011 Scottish Census, the British Deaf Association estimates there are 151,000 BSL users in the UK, of whom 87,000 are Deaf. By contrast, in the 2011 England and Wales Census 15,000 people living in England and Wales reported themselves using BSL as their main language. People who are not deaf may also use BSL, as hearing relatives of deaf people, sign language interpreters or as a result of other contact with the British Deaf community. The language makes use of space and involves movement of the hands, body, face and head.

<span class="mw-page-title-main">William Stokoe</span> American linguist (1919–2000)

William Clarence “Bill” Stokoe Jr. was an American linguist and a long-time professor at Gallaudet University. His research on American Sign Language (ASL) revolutionized the understanding of ASL in the United States and sign languages throughout the world. Stokoe's work led to a widespread recognition that sign languages are true languages, exhibiting syntax and morphology, and are not only systems of gesture.

Auslan is the sign language used by the majority of the Australian Deaf community. Auslan is related to British Sign Language (BSL) and New Zealand Sign Language (NZSL); the three have descended from the same parent language, and together comprise the BANZSL language family. As with other sign languages, Auslan's grammar and vocabulary is quite different from spoken English. Its origin cannot be attributed to any individual; rather, it is a natural language that emerged spontaneously and has changed over time.

Signing Exact English is a system of manual communication that strives to be an exact representation of English language vocabulary and grammar. It is one of a number of such systems in use in English-speaking countries. It is related to Seeing Essential English (SEE-I), a manual sign system created in 1945, based on the morphemes of English words. SEE-II models much of its sign vocabulary from American Sign Language (ASL), but modifies the handshapes used in ASL in order to use the handshape of the first letter of the corresponding English word.

The American Manual Alphabet (AMA) is a manual alphabet that augments the vocabulary of American Sign Language.

Tactile signing is a common means of communication used by people with deafblindness. It is based on a sign language or another system of manual communication.

Manually Coded English (MCE) is an umbrella term referring to a number of invented manual codes intended to visually represent the exact grammar and morphology of spoken English. Different codes of MCE vary in the levels of adherence to spoken English grammar, morphology, and syntax. MCE is typically used in conjunction with direct spoken English.

<span class="mw-page-title-main">Home sign</span> Gestural communication system

Home sign is a gestural communication system, often invented spontaneously by a deaf child who lacks accessible linguistic input. Home sign systems often arise in families where a deaf child is raised by hearing parents and is isolated from the Deaf community. Because the deaf child does not receive signed or spoken language input, these children are referred to as linguistically isolated.

A contact sign language, or contact sign, is a variety or style of language that arises from contact between deaf individuals using a sign language and hearing individuals using an oral language. Contact languages also arise between different sign languages, although the term pidgin rather than contact sign is used to describe such phenomena.

<span class="mw-page-title-main">Stokoe notation</span> Phonemic script for sign languages

Stokoe notation is the first phonemic script used for sign languages. It was created by William Stokoe for American Sign Language (ASL), with Latin letters and numerals used for the shapes they have in fingerspelling, and iconic glyphs to transcribe the position, movement, and orientation of the hands. It was first published as the organizing principle of Sign Language Structure: An Outline of the Visual Communication Systems of the American Deaf (1960), and later also used in A Dictionary of American Sign Language on Linguistic Principles, by Stokoe, Casterline, and Croneberg (1965). In the 1965 dictionary, signs are themselves arranged alphabetically, according to their Stokoe transcription, rather than being ordered by their English glosses as in other sign-language dictionaries. This made it the only ASL dictionary where the reader could look up a sign without first knowing how to translate it into English. The Stokoe notation was later adapted to British Sign Language (BSL) in Kyle et al. (1985) and to Australian Aboriginal sign languages in Kendon (1988). In each case the researchers modified the alphabet to accommodate phonemes not found in ASL.

Catalan Sign Language is a sign language used by around 18,000 people in different areas of Spain including Catalonia. As of 2012, the Catalan Federation for the Deaf estimates 25,000 LSC signers and roughly 12,000 deaf people around the Catalan lands. It has about 50% intelligibility with Spanish Sign Language (LSE). On the basis of mutual intelligibility, lexicon, and social attitudes, linguists have argued that LSC and LSE are distinct languages.

Singapore Sign Language, or SgSL, is the native sign language used by the deaf and hard of hearing in Singapore, developed over six decades since the setting up of the first school for the Deaf in 1954. Since Singapore's independence in 1965, the Singapore deaf community has had to adapt to many linguistic changes. Today, the local deaf community recognises Singapore Sign Language (SgSL) as a reflection of Singapore's diverse culture. SgSL is influenced by Shanghainese Sign Language (SSL), American Sign Language (ASL), Signing Exact English (SEE-II) and locally developed signs.

American Sign Language literature is one of the most important shared cultural experiences in the American deaf community. Literary genres initially developed in residential Deaf institutes, such as American School for the Deaf in Hartford, Connecticut, which is where American Sign Language developed as a language in the early 19th century. There are many genres of ASL literature, such as narratives of personal experience, poetry, cinematographic stories, folktales, translated works, original fiction and stories with handshape constraints. Authors of ASL literature use their body as the text of their work, which is visually read and comprehended by their audience viewers. In the early development of ASL literary genres, the works were generally not analyzed as written texts are, but the increased dissemination of ASL literature on video has led to greater analysis of these genres.

Nepalese Sign Language or Nepali Sign Language is the main sign language of Nepal. It is a partially standardized language based informally on the variety used in Kathmandu, with some input from varieties from Pokhara and elsewhere. As an indigenous sign language, it is not related to oral Nepali. The Nepali Constitution of 2015 specifically mentions the right to have education in Sign Language for the deaf. Likewise, the newly passed Disability Rights Act of 2072 BS defined language to include "spoken and sign languages and other forms of speechless language." in practice it is recognized by the Ministry of Education and the Ministry of Women, Children and Social Welfare, and is used in all schools for the deaf. In addition, there is legislation underway in Nepal which, in line with the UN Convention on the Rights of Persons with Disabilities (UNCRPD) which Nepal has ratified, should give Nepalese Sign Language equal status with the oral languages of the country.

In sign languages, the term classifier construction refers to a morphological system that can express events and states. They use handshape classifiers to represent movement, location, and shape. Classifiers differ from signs in their morphology, namely that signs consist of a single morpheme. Signs are composed of three meaningless phonological features: handshape, location, and movement. Classifiers, on the other hand, consist of many morphemes. Specifically, the handshape, location, and movement are all meaningful on their own. The handshape represents an entity and the hand's movement iconically represents the movement of that entity. The relative location of multiple entities can be represented iconically in two-handed constructions.

The sociolinguistics of sign languages is the application of sociolinguistic principles to the study of sign languages. The study of sociolinguistics in the American Deaf community did not start until the 1960s. Until recently, the study of sign language and sociolinguistics has existed in two separate domains. Nonetheless, now it is clear that many sociolinguistic aspects do not depend on modality and that the combined examination of sociolinguistics and sign language offers countless opportunities to test and understand sociolinguistic theories. The sociolinguistics of sign languages focuses on the study of the relationship between social variables and linguistic variables and their effect on sign languages. The social variables external from language include age, region, social class, ethnicity, and sex. External factors are social by nature and may correlate with the behavior of the linguistic variable. The choices made of internal linguistic variant forms are systematically constrained by a range of factors at both the linguistic and the social levels. The internal variables are linguistic in nature: a sound, a handshape, and a syntactic structure. What makes the sociolinguistics of sign language different from the sociolinguistics of spoken languages is that sign languages have several variables both internal and external to the language that are unique to the Deaf community. Such variables include the audiological status of a signer's parents, age of acquisition, and educational background. There exist perceptions of socioeconomic status and variation of "grassroots" deaf people and middle-class deaf professionals, but this has not been studied in a systematic way. "The sociolinguistic reality of these perceptions has yet to be explored". Many variations in dialects correspond or reflect the values of particular identities of a community.

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    77. 1 2 These are Adamorobe Sign Language, Armenian Sign Language, Australian Aboriginal sign languages, Hindu mudra, the Monastic sign languages, Martha's Vineyard Sign Language, Plains Indian Sign Language, Urubú-Kaapor Sign Language, Chinese Sign Language, Indo-Pakistani Sign Language (Pakistani SL is said to be R, but Indian SL to be A, though they are the same language), Japanese Sign Language, and maybe the various Thai Hill-Country sign languages, French Sign Language, Lyons Sign Language, and Nohya Maya Sign Language. Wittmann also includes, bizarrely, Chinese characters and Egyptian hieroglyphs.
    78. 1 2 These are Providencia Island, Kod Tangan Bahasa Malaysia (manually signed Malay), German, Ecuadoran, Salvadoran, Gestuno, Indo-Pakistani (Pakistani SL is said to be R, but Indian SL to be A, though they are the same language), Kenyan, Brazilian, Spanish, Nepali (with possible admixture), Penang, Rennellese, Saudi, the various Sri Lankan sign languages, and perhaps BSL, Peruvian, Tijuana (spurious), Venezuelan, and Nicaraguan sign languages.
    79. Wittmann adds that this taxonomic criterion is not really applicable with any scientific rigor: Auxiliary sign languages, to the extent that they are full-fledged natural languages (and therefore included in his survey) at all, are mostly used by the deaf as well, and some primary sign languages (such as ASL and Adamorobe Sign Language) have acquired auxiliary usages.
    80. Wittmann includes in this class Australian Aboriginal sign languages (at least 14 different languages), Monastic sign language, Thai Hill-Country sign languages (possibly including languages in Vietnam and Laos), and Sri Lankan sign languages (14 deaf schools with different sign languages).
    81. Wittmann's references on the subject, besides his own work on creolization and relexification in spoken languages, include papers such as Fischer (1974, 1978), Deuchar (1987) and Judy Kegl's pre-1991 work on creolization in sign languages.
    82. Wittmann's explanation for this is that models of acquisition and transmission for sign languages are not based on any typical parent-child relation model of direct transmission which is inducive to variation and change to a greater extent. He notes that sign creoles are much more common than vocal creoles and that we can't know on how many successive creolizations prototype-A sign languages are based prior to their historicity.[ clarification needed ]
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    Bibliography

    Further reading

    Note: the articles for specific sign languages (e.g. ASL or BSL) may contain further external links, e.g. for learning those languages.