Research – Sign language as a communication option for non-hearing impaired children and adults

DOCUMENT 3 FOI 24/25 - 0002

Research – Sign language as a communication option for non- hearing impaired children and adults

          Two briefs for this request exist.
                    1)  Relates to the efficacy of teaching sign language to non-verbal or
                      minimally verbal children

Brief 2) Relates to the delivery of sign language to hearing impaired adults rather than other conventional options (hearing aids etc.) Please refer to the request for further detail.

Date 03/03/2021 Jean redacted: s22(1)(a)(ii) - irre - Senior Technical Advisor (TAB) Requester(s) redacted: s22(1)(a)(ii) - irrele Judith Senior Technical Advisor (TAB) Researcher Jane redacted: s22(1)(a)(ii) - irrelev (Research Team Leader - TAB)

Cleared

Please note:

The research and literature reviews collated by our TAB Research Team are not to be shared external to the Branch. These are for internal TAB use only and are intended to assist our advisors with their reasonable and necessary decision-making.

Delegates have access to a wide variety of comprehensive guidance material. If Delegates require further information on access or planning matters they are to call the TAPS line for advice.

The Research Team are unable to ensure that the information listed below provides an accurate & up-to-date snapshot of these matters.

1 Contents

2 Summary ……………………………………………………………………………………………………………………….. 2 3 Australian Sign Language (AUSLAN)…………………………………………………………………………………… 3 4 What is Key Word Sign? …………………………………………………………………………………………………… 3 5 Signed Exact English ………………………………………………………………………………………………………… 3 6 Diagnosis of Autism – non-verbal deficits …………………………………………………………………………… 4 7 Literature investigating the use of signs for non-verbal individuals with autism ……………………… 4 8 Learning a second language as an adult …………………………………………………………………………… 17 9 Delivery of sign language training to those with early hearing loss ……………………………………… 19

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9.1 Difficulties in learning a signed language ………………………………………………………………….. 19 10 Deaf Culture ……………………………………………………………………………………………………………… 20 10.1 Values …………………………………………………………………………………………………………………… 20 10.2 Behaviour ……………………………………………………………………………………………………………… 21 10.3 Customs………………………………………………………………………………………………………………… 21 References ………………………………………………………………………………………………………………………….. 23

2 Summary

1)  There is no peer reviewed evidence that shows that sign language (Auslan, American Sign
   Language, British Sign Language etc.) is an effective communication system for nonverbal on
   minimally verbally children with an autism diagnosis (literature tends to focus on autism
    rather than intellectual disability)
         a.  Literature shows that some children with autism (usually higher functioning with
         good motor coordination) are able to pick up various manual signs and use them to
         communicate. Although the term ‘sign language’ is used in these studies, it is more
        commonly Signed Exact English or a type of Key Word Sign being taught. Children
           are generally taught a small subset of signs (normally those that are iconic) and are
          not learning pure forms of sign language such as Auslan.
         b.  Literature investigating aided and unaided AAC devices for children with autism
        show that aided devices such as speech generating devices are more commonly
           preferred and are learnt more quickly (refer to Table 1 for more in-depth results).
          c.  Due to the cognitive and motor demands, as well nonverbal communications skills
           (eye contact, gestures, facial expression) required to master sign language it is not
         an appropriate form of communication for non-hearing impaired children with
           autism.
         d.  Manual signs should be used as part of a ‘total communication’ approach which
           included aided AAC interventions so they can communication with a range of
             individuals

2)  There is no peer reviewed evidence that investigates the efficacy or advantages of delivering
    sign language over other rehabilitations options (hearing aids, remote microphones etc.) for
   those with acquired hearing loss/progressive hearing loss
         a.  Literature suggests there is a critical period when it comes to learning a second
          language as an adult. Although there is no consensus, the cut off is somewhere
         around the age of 17 to 18.
         b.  Learning sign language is difficult and requires extensive practice/input (approx.
         1000 hours). There are few opportunities for new signers to immerse themselves in
          the language due to small number of native Auslan speakers
          c.  Deaf culture can make it difficult for new signers to be accepted into the community

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3 Australian Sign Language (AUSLAN)

Sign language refers to the use of manually produced signs to convey information or ideas. It is the method of communication used by most moderately or profoundly deaf persons. Sign language is not just a manual representation of oral language; rather, it is an independent language [1]. When combined with facial expression and gestures, it conveys rich meaning, humour, anguish, and many subtleties of communication [1].

Descriptive research and publications have established sign languages as syntactically complex languages with distinctive morphological, phonological and sociolinguistic features [2]. At present, there are sixty-two handshapes listed in the Signs of Australia dictionary of Auslan [3]. Of these sixty-two handshapes, thirty-seven are the core handshapes used and the other twenty-five are seen as non-significant variations of these (the exception to this is with productive signing where small differences can represent a different and precise meaning) [3].

Fingerspelling is generally mixed in with signing and is especially used for spelling nouns (place names, people’s names, objects’ names) or for spelling words that don’t have a sign. Fingerspelling is using your hands to represent the letters of a writing system. In English, this means using 26 different hand configurations to represent the 26 letters of the English alphabet. As such, fingerspelling is not a signed language in and of itself, rather it is a manual code for representing the letters of the English alphabet [3].

It is now increasingly recognised that signing deaf people constitute a group like any other non- English-speaking language group in Australia, with a distinct sub-culture recognised by shared history, social life and sense of identity, united and symbolised by fluency in Auslan.

4 What is Key Word Sign?

Key Word Sign (KWS) is a type of augmentative and alternative communication (AAC). It is a way of communicating that uses hand signs to represent the main or key words in a sentence at the same time as the words are spoken [4]. Key Word Sign was formerly known as Makaton in Australia and is also known as manual signing [4].

There is very little research on KWS as an intervention for children with autism exists [5, 6]. There are some studies with positive outcomes that investigate educator’s perception, experience and ability to learn KWS [7, 8] as well as in the intellectual disability population [9].

5 Signed Exact English

Signing Exact English (SEE) is a sign system aimed at representing English vocabulary and syntax as literally as possible by providing visual access to English morphology [10]. It uses Sign Language signs

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(American, British, Australian etc.), as well as invented signs, in combination with signed representations of English affixes; the invented signs are necessary for (a) representing English grammatical words that do not exist in ASL (e.g., “the”) and (b) differentiating English synonyms that correspond to the same ASL sign [10]. Signs are produced sequentially, in English word order, in conjunction with the mouth movements of English, with the goal of establishing a one-to-one mapping between signs and English words [10].

Signed English was developed by teachers of the deaf and other professionals to assist in the English literacy development of deaf (sign language using) children [11].

6 Diagnosis of Autism – non-verbal deficits

Professionals diagnose autism spectrum disorder on the basis of difficulties in two areas – ‘social- communication’, and ‘restricted, repetitive and/or sensory behaviours or interests’.

The DSM-5 criteria lists the below criteria in the ‘social communication’ domain [12].

Deficits in nonverbal communicative behaviours used for social interaction, ranging, for example, from poorly integrated verbal and nonverbal communication; to abnormalities in eye contact and body language or deficits in understanding and use of gestures; to a total lack of facial expressions and nonverbal communication.

Eye contact, gestures and facial expressions are key components in sign language. Facial and head movements are used in sign languages at all levels of linguistic structure. At the phonological level some signs have an obligatory facial component in their citation form [13].

Because of the nonverbal deficits associated with autism it is highly unlikely that proficiency in sign language will ever be achieved, therefore, it isn’t inappropriate as a communication technique.

7 Literature investigating the use of signs for non-verbal

individuals with autism

The literature search did not identify any peer reviewed research that investigated the delivery or efficacy of sign language training to individuals diagnosed with ASD.

In the literature, the terms sign language, manual signs and finger spelling are often used interchangeably. In reality, one of two systems are being used and consist of 1) taking various signs from the language of the deaf community (Auslan, American Sign Language or British Sign Language) and putting the signs in English order or 2) using SEE signs, which is a system that attempts to duplicate English syntax and morphology in the manual mode. The sign language input in most cases has been augmented by the teacher or therapist’s simultaneous use of spoken English and is not the same sign language that is utilised by the deaf community [14].

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For many years, AAC interventions for individuals with ASD focused primarily on the use of unaided communication strategies, and sign language in particular [15]. The literature review (see Table 1 for full review) revealed that studies investigating the effectiveness of manual sign-based interventions are generally;

1)  Case series designs with no control/comparison group
2) Low in quality
         a.  provide no measure of reliability, few are generalizable to the greater ASD
         community, and many fail to disclose sufficient detail for either clinical application
           or experimental replication

Results show a wide range in individual outcomes;

1) Some participants appears to readily learn signs and others are unable to attain even the
  most basic signing skills
         a.  Very low-functioning autistic children do not appear to make as rapid progress
2)  Studies mostly taught a small number of basic signs and productive combinations were
    less frequently observed
3) No evidence to suggest that signing leads to a meaningful increase in speech production
         a.  signs alone or in conjunction with speech training is not harmful or in any way
           contraindicated (early theories were that teaching sign language would be harmful
           to speech production)

Proponents of sign language training have reported several advantages over the delivery of speech training for children with ASD:

1) Many individuals with ASD or other developmental disorders cannot echo sounds, but they
   can imitate at least a few gross motor movements presented by communication partners.
         a.  the facilitator can make use of physical prompting and fading procedures
2) Some signs resemble the object or action it represents which may help people with ASD to
    learn rapidly. Oral speech, on the other hand, is not iconic.
         a.  Example: the sign for drink is produced by moving a hand close to the mouth and
           turning it slightly back and forth as if holding a cup and drinking from it.
3)  Manual signs are unaided and free from access to external supports, are highly portable and
   cannot be left behind [15]

One proposed explanation for the failure of sign language training in many individuals with ASD is that the successful acquisition and use of sign language as a communicative tool is dependent on the ability to form a variety of manual motor signs, and there are many individuals with ASD who do not possess the fine motor skills required [16, 17]. Mirenda and Erickson [18] outline “the three I’s” that contribute to successful sign language acquisition:

1.  Imitation
2.  Iconicity, and
3.   Intelligibility

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They maintain that children with ASD demonstrate a lack of imitation, symbolic representation, and motor coordination/planning skills, while the successful acquisition and use of sign language relies largely on the possession of these abilities. In each of these proposed explanations, deficits and delays in motor and motor-related skills are key to explaining why children with ASD generally fail to develop both sign language-based communication and speech and language skills [16].

Following the discovery of visual processing strengths that many children with ASD demonstrate, greater attention was paid to the application of aided strategies such as pictographic symbol sets and other graphic sets/systems to enhance communication. From a practical perspective, graphic symbols (especially when highly iconic) seem to present several potential advantages over manual signs or abstract symbols [15]:

1) Demands on memory and cognitive skill may be lower
         a.  Picture-based systems are concrete, remain present to refer back to (unlike manual
             signs, which are transient), and many resemble their referents [19, 20]
2)  Motor ability requirements are lower
         a.  Fine motor difficulties are common in individuals with ASD, thus causing difficulty in
            learning manual signs [19]
3)  Graphic symbols are more easily understood by unfamiliar communication partners and are
    easier to prompt
         a.  A study by Rotholz, Berkowitz [21] highlights this point: Adolescents with ASD were
           taught to use both manual signs and PECS to order food in a restaurant. None of the
            students’ manual signs were understood, relative to successful request rates of
         between 80% and 100% when PECS were used. Thus, the intelligibility of an AAC
          approach is an important consideration when deciding upon which strategy to teach
            [22]
4)  Lower training demands placed on communication partners compared to when learning
  manual signs
         a.  High teaching costs associated with manual signing and the need to establish
            prerequisite skills such as eye contact and imitation [22].

In more recent years, low and high technology aided ACC technologies have been used successfully with individuals with ASD and appear to be more promising communication strategies [20, 23, 24]. A systematic review by Gevarter, O’Reilly [24] compared aided and unaided communication options across 10 studies (n = 33).

•  Seven of the studies comparing mand acquisition of sign to picture exchange (PE) systems
   and/or speech generating devices (SGDs) found that aided systems were more effective than
    sign for 14 participants, aided and unaided systems were equally effective for 12, and data
  were inconclusive for 1 participant.
•  Three studies attempted to account for differential outcomes among learners provided
   support for the fact that PE systems were more effective than sign when participants had
   low motor imitation abilities.
•   Four studies assessed preference, and found that aided systems were preferred by 10
    participants (3 PE or picture card and 7 SGD) and sign was preferred by one.

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Overall, this review suggests thataided systems are acquired quicker and generally preferred by users over manual signing. This finding was also supported by Couper, van der Meer [23] who suggested that for some children, acquisition may be quicker when learning a preferred option.

Manual signs are still a useful means of communication, however, might best be included as one component of a multimodal communication system that also includes graphic symbols, SGDs, and an individual’s extant communication modalities (i.e. gestures, vocalisations and facial expressions) [15].

8 Cost effectiveness

No health economic analysis or cost effectiveness studies have been conducted that compare sign language (Auslan) to other AAC devices. However, sign language training is considered to be high cost due to the time consuming training compared to low tech AAC such as picture exchange [25].

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9 Learning a second language as an adult

The role that age plays in second language learning /acquisition (SLA) has been the central topic of many studies in SLA over various decades. Biological, social, and psychological maturation phenomena are factors which have been hypothesised as reasons why adults find it more difficult to learn a second language [29].

The concept of a critical age for learning was first suggested in 1959 when the age of 9 was claimed as the limit in terms of successful language learning because of physiological constraints such as progressive loss of brain plasticity (this age is also considered the cut off for visual development) [30]. The critical period has been researched extensively with no agreement on what the upper age limit is [29, 30]. Inconsistencies have been found across various studies relating to the impact that age has on learning different language domains [29, 30]:

1)  Onset and offset – no consensus reached, although newer research has suggested the offset
       is somewhere between 17 and 18 years of age [31].
2)  Language domains – most researchers agree that pronunciation/phonology is more affected
   by age than other language domains.
3)  Existence of a critical period – no consensus has been reached so far, but age is believed to
  be an important factor in SLA.

Neuroplasticity begins to decrease after adolescence, making it practically impossible or very difficult for adult students to reach a native language level, especially when “input” levels are small [32]. A combination of individual and contextual factors determines the learning journey and affects the time each individual needs to make progress [33]. Although there is no unanimous agreement as to how many hours are needed to gain increasing language proficiency, attempts have been made to produce learning time estimates [33]. The table below provides estimates for fast and slow learners using the Common European Framework for Reference of Languages (CEFR) [33]. For example, it would take 4491 hours for a slow learner to go from a basic user (A1) to a proficient user (C1).

Basic user = A1 & A2 Independent user = B1 & B2 Proficient user = C1 & C2

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Adult learners often lack the level of linguistic knowledge that their younger peers possess because of factors that stem from cognitive and affective limitations. These limitations have been described by Bernal Castañeda [32].

Cognitive limitations

•  A decrease in memory levels: Adult students generally present a reduced ability to
   memorize, which limits learning when acquiring the second language lexicon and grammar.
    This leads to the belief that translation is an indispensable tool for learning the language and
   the need to search for equivalences in their native language [34, 35].
•   Loss of sensory acuity: older students lose their ability to imitate sounds and to memorize,
   consequently they are forced to start a production process based on trial/error and the oral
   response is decidedly slower [34]. Thus, in addition to the cognitive factors associated with
    late language acquisition, adult students must also face progressive losses in sensory acuity
    that have accumulated since their adolescence.
•  Tendency to fossilization: Adult students tend to fossilize their knowledge of the target
   language. They generally tend to systematize errors, and their lack of correction or habit can
    lead to the repetition of such errors and, consequently, the lack of acquisition. The most
  commonly investigated areas in the field of fossilization are grammar and pronunciation [30,
    34].
•  Language 1 Transfer: Adult learners generally feel a more constant need to transfer the
   knowledge they possess in their L1 to learning a second language. Such transfer can result in
   a positive outcome when the common characteristics of certain languages encourage
    learning through equivalences and comparisons. However, there is a thin line between
     facilitation of an L2 through transference and the constant and negative interference of L1 in
      all L2 skills [35, 36]. This has also been termed ‘tyranny of the mother tongue’ where the
    native language comes to dominate the linguistic map space and the second language finds
        it hard to compete [37].

Affective limitations

•  Language anxiety: Anxiety is an important variable in adult L2 learning because students
    face an elevated pressure to acquire a second language at the same pace or rhythm as their
   younger peers. Frequently the outcome is not as positive as adults would expect, which
    leads to stress and a very high pressure in class. Recent studies argue that language anxiety
       is a complex and dynamic construct and that it is linked to psychological variables such as
     self and personality [38].
•   Self-concept: Adult students’ self-concept is also crucial and directly affects motivation in L2
     class [39]. Adult students usually present a distorted self-concept or image due to a lack of
   confidence in themselves and insecurities towards L2 learning and new methodologies [39].
•   L2 enjoyment: Interest and enjoyment towards learning a foreign language are the key
    points of success in linguistic education. When teaching a second language subject in age-
   heterogeneous contexts, a sense of enjoyment must be found [32].

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10 Delivery of sign language training to those with early

hearing loss

No peer reviewed research could be sourced on the efficacy or advantages of delivering sign language as a communication option for those with acquired hearing loss/progressive hearing loss. Research in the area of early intervention exclusively focuses on the delivery of sign language to deaf and hearing impaired children, often at the time a cochlear implant is provided.

A systematic review was conducted in 2018 to investigate the effectiveness of early sign and oral language intervention compared with oral language intervention only for children with permanent hearing loss [40]. The review found there is no evidence that adding sign language facilitates spoken language acquisition. However, the review also found no conclusive evidence that adding sign language interferes with spoken language development. Overall, the literature related to intervention methods for children with hearing loss lacks properly designed cohort studies of today’s generation of children.

10.1 Difficulties in learning a signed language

A major misconception about sign language is that it is an easily learnt, picture-like language [41]. This misunderstanding is due partly to the fact that some of the first basic signs learned may be thought of as iconic (e.g. signs for eat, drink and sleep) [41]. Sign language has been established as a distinctive language separated from other languages. It contains the linguistic components that constitute a sophisticated, independent language [41].

It has been argued that learning sign language is as difficult for native English speakers as learning Chinese or Japanese [42]. The ‘foreignness’ of sign language makes it more difficult to learn than, perhaps, Spanish or French [35]. Rosen [43] noted that second language learners of sign language often make phonological errors in producing signs, which makes the signing seem awkward and unnatural. The Defense Language Institute have grouped languages into four categories in terms of their level of difficulty for native English speakers to learn [28]. The degree of difficulty is based on how long it takes to learn the target language before reaching a proficiency level of two (limited working proficiency) on a scale of 0 (memorised proficiency) to 5 (functionally native proficiency) [41]. There is no published guide on which category sign language falls into. Some authors have suggested Category 2 (36 weeks, 1080 hours) or Category 4 (44 weeks, 1320 hours) [33].

One of the problems in learning a signed language as a second language is the limited opportunity for immersion in the language and the associated culture that many learners experience. In Australia, there is estimated to be about 6,500 signing deaf people/ ‘native speakers’. This number would more than double if all hearing people who use Auslan were included [44]. A ‘native speaker’ is defined as someone who has learned sign language from birth through Deaf parents – which is a small minority group [42]. Immersion is often only available to learners by attending and participating in activities in the Deaf community, such as social events. For many reasons it may be Research – Sign language as a communication option for non-hearing impaired children and adults Page 19 of 25

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difficult for hearing individuals to access such situations. In some cases such difficulties may be exacerbated by the often-held perception by some Deaf people that hearing people are members of an oppressive majority group [41, 42]. Alternatively, some Deaf adults may warmly embrace the families of deaf children that are endeavouring to learn to sign. Further information on Deaf culture is covered below.

A major barrier in providing sign language as the prominent communication support for adults with acquired hearing loss is that family members/support networks would also need to learn sign language to enable communication and increased participation. If parents/spouse can sign, but siblings or other extended family cannot, then the deaf individual will miss out on much of the conversations with other people [42].

11 Deaf Culture

The term “Deaf culture” is used to identify a set of beliefs, practices, and a common language shared by a group of deaf people [45]. Culturally Deaf people prefer to look at their deafness positively as a different culture instead of as impairment, which is at odds with the medical/professional community’s view of deafness as an illness [45].

Sign language is at the centre of Deaf culture and community and the single most unifying characteristic. Anyone who does not value sign language is unlikely to either feel comfortable within the Deaf culture, or to be accepted by it. Those who use sign language, especially as a first language, are viewed as members of a tightly knit in-group, or “Deaf culture,” while those who are not “pure” signers are viewed as members of the out-group, or

disabled or impaired and dislike being referred to as

The long goodbye: When Deaf people are leaving a gathering of friends (and Deaf people who belong to the Deaf community tend to have many friends) they take much longer than most hearing people do to say goodbye. The custom is to seek out one’s friends and in the process of saying goodbye, discuss when they next expect to meet.

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