Seminar on Speech and Language Processing for Augmentative

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Seminar on Speech and Language Processing for

Augmentative and Alternative Communication

Class 10: More Symbol Systems

Presenter:

Masoud Rouhizadeh

 1) Transparency and ease of learning of symbols represented by Blissymbolics, PCS, and Picsyms , Mizuko,

1987, Augmentative and Alternative Communication.

 2) Use of picture dictionaries to promote written communication by students with hearing and cognitive impairments, Cohen et al, 2001, Augmentative and

Alternative Communication.

 3) Generalization of a pictorial alternative communication system across instructors and distance.

Ganz et al, 2008, Augmentative and Alternative

Communication.

Paper #1: Mizuko, 1987

Transparency and Ease of Learning of Symbols Represented by Blissymbols, PCS, and Picsyms

 Determining whether significant differences existed among normally developing 3-year-old children in transparency and in the learning of symbols from three different graphic symbol systems:

 Blissymbols

 Picture Communication System [PCS]

 Picsyms

Factors for selecting nonspeech symbol systems

 Which nonspeech symbol system is the most appropriate for a particular nonspeaking individual?

 What factors should be considered when selecting a nonspeech symbol system?

 Ease of acquisition (Clark, 1981 and others)

 Iconicity (which may facilitate symbol communication development among nonspeaking individuals) (Fristoe and Lloyd, 1979)

Iconicity

 The visual representation depicted by nonspeech symbols, in particular their ability to visually resemble or suggest their referents .

 Bellugi and Klima (1976): the degree to which the elements of a sign or symbol are related to the visual aspects of what is denoted.

Symbols which are highly suggestive of their referents. Their meaning can be readily guessed by naive viewers.

(Transparent symbols)

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Symbols which may not be readily guessable, but the viewer is able to perceive a relationship between the symbol and its meaning (Translucent symbols)

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Abstract symbols with no apparent relationship to its referent, which are not guessable. (Opaque symbols)

Transparency vs translucency

Transparency: guessing the symbol when given the gloss or guessing the gloss when shown the symbol.

Translucency: agreement regarding the relationships between a symbol and its referent.

Iconicity in nonspeech symbols

 Nonspeech symbols with high iconicity were more easily learned by individuals with mental retardation and/or autism than nonspeech symbols with low iconicity.

 Clark (1984) suggested that nonspeaking individuals with apparent cognitive delays may need a system that is iconic and easily learned.

 Conversely, when little or no cognitive delay is present in a nonspeaking individual, ease of learning and iconicity may not be critical factors.

The purpose of the study

 To investigate transparency and the ease of learning of referents represented by different graphic symbol systems (Blissymbols, PCS, Picsyms).

 Also to investigate whether there are learning and transparency differences across different graphic symbol systems within three different word categories

(nouns, verbs, descriptors).

Blissymbols , Picsyms and PCS

Blissymbols and Picsyms

 pictographic symbols (drawings that resemble their referents),

 ideographic symbols (drawings that symbolize the idea rather than the name of a referent)

 arbitrary symbols (drawings which do not have a perceptual or conceptual relationship to its referent), whereas

PCS: mainly pictographic symbols.

Picture Communication Symbols

(PCS)

PCS (no word version)

Bliss

Picsyms

Subjects

36 subjects from a group of normally developing children, 29 to 44 months of age

1. English spoken as the primary language

2. no apparent handicaps

3. vision and hearing within normal limits

4. chronological age appropriate vocabulary recognition skills

5. lack of familiarity with any of the three symbol systems

Materials

 Three test booklets each containing 45 items from one of the symbol systems

 15 nouns, 15 verbs and 15 descriptors were randomly chosen for the learning tasks from a pool of referents

 The referent should have the following criteria:

1. listed in the PCS Dictionary, Picsyms Dictionary and

Blissymbolics for Use.

2. high frequency of occurrence

3. they could not be used as a noun and a verb (e.g., drink)

4. they could not be used as a body part or person

Procedures

 45 items of the booklet

 3 learning trials

 Transparency and learning tasks

 showing the subject a stimulus page with four different symbols and asking the subject to select the symbol that best matched the spoken label

Results

 The Scheffe test for means revealed significant differences between Blisymbols and both

PCS and Picsyms.

 Overall scores were significantly lower with Blissymbols than with the other two symbol systems.

 There were significant differences between PCS and Picsyms for descriptors and verbs.

Results

Discussion

 Fewer Blissymbols were correctly identified than either PCS or

Picsyms

 Picsyms and PCS were similar for nouns, while PCS was more transparent than Picsyms for verbs and descriptors.

 Learning: more PCS symbols were learned over three trials than either Picsyms or Blissymbols : symbols judged to be iconic are learned more easily than symbols that are not iconic.

 PCS and Picsyms may be used with physically disabled children with spoken language comprehension skills near 3 years, if they need to acquire an immediate means of communication.

 Conversely, when selecting a system for older persons with severe physical disabilities with little or no cognitive delay, ease of acquisition may not be an important factor.

Paper #2: Cohen et al, 2001

Use of picture dictionaries to promote written communication by students with hearing and cognitive impairments

 Students with deafness and limited literacy skills at communitybased vocational sites

 Students were taught to use picture dictionaries—small notebooks consisting of symbols with corresponding words—to write printed messages to their communication partners.

Introduction

 Implementing other forms of communication can be challenging in vocational settings such as community-based vocational training (CBVT) sites.

 CBVT sites: businesses in the community, agreed to provide work experience opportunities to high school students

 Additional forms of communication should be available for untrained coworkers, customers and students

 Interpreters? not always available in vocational settings

Communication partners

 Primary: teachers and family members

 Regular: immediate coworkers

 Primary and regular communication partners have the opportunity to learn sign, gestures, and other effective methods of interaction.

 Irregular: a coworker working in a different area

 Strangers: a customer

 Irregular communication partners and strangers have little or no consistent contact with the student

Symbol-Based Forms of Communication

 Such as : PCS, Bliss, Picsyms

 Negative attitude:

 Symbol-based form of communication is different from the gestures and written notes

 So they may be a visible sign of students' reduced literacy capabilities

 Students may not use symbol-based systems because of concerns that such systems make them appear “retarded” to other people

Picture Dictionaries

 A series of pictures or symbols with printed labels, placed in an alphabetical or categorical sequence

Picture Dictionaries

 Assuming that the student have sufficient writing skills to look up and copy words, they can refer to a picture dictionary for the desired picture, copy the associated printed words onto a pad of paper, and give the communication partner the written message.

 Less negative attitude:

 Because the picture symbols are hidden from the communication partner and the product is a written note, use of a picture dictionary should be less stigmatizing and more motivating than a standard communication board.

Participants

Materials

 Symbol Communication Boards

 multiple pages with 15 symbols per page of both sitespecific and job-related vocabulary, general vocabulary, and social vocabulary.

 Picture Dictionaries

 Individualized picture dictionaries with pages of symbols accompanied by written word(s) or short phrases describing them.

Preintervention Assessment

 Students were assessed with regard to writing skills

 Copying the words

 Legibility of writing

 Copying speed

 Comprehension

 Eliminating the words that the students could spell and sign

Picture Dictionaries Vocabulary Selection

 The investigator observed the students at each job site and recorded the vocabulary words that were needed for them to perform each task

 Interviews were conducted with the students and their job coaches, coworkers, and site supervisors

 Target vocabulary words were selected out of a pool based on their frequency of use, their potential usefulness for job completion, and the likelihood that the student need that word

 Most of the selected words were job specific and consisted of nouns representing the items necessary for job completion and directive phrases such as I NEED, WHERE IS, or SHOW ME

 The social phrases PLEASE and THANK YOU and the names of regular communication partners were also included

Instructional Procedure

 Teaching symbol meanings and the picture dictionaries

 The distinction between the symbol-based boards and picture dictionaries explained to minimize any negative reactions

 Locating an appropriate symbol or word in response to specific queries, copying the words associated with each symbol ...

Design and Data Collection

At baseline, data were collected on the student’s frequency of board use at CBVT sites and their use of any other forms of aided or unaided communication.

 During the first training phase, Treatment S (S = symbol), students were taught the meanings of the symbols in their picture dictionaries in a school setting.

 During the second training phase, Treatment M (M = mechanism), students were taught the mechanics of using their picture dictionaries (locating symbols, copying, ripping out the note paper, handing it to a communication partner)

 During the generalization phase data were recorded on (a) the forms of communication each student elected, (b) the content of the message, and (c) whether the communication was an initiation or a response.

Discussion

 Using picture dictionaries for note writing can be an effective form of expressive communication at the job site for students with deafness and mild to borderline mental retardation.

 The use of picture dictionaries resulted in fewer missed opportunities to communicate.

 Increased ability to communicate on for specific work-related items

 Change in the content of messages with and without picture dictionaries.

 One drawback is that such use assumes literacy skills on the part of the communication partner, which may not always be the case.

 Another problem is that communication partners may assume that the writer has a higher level of literacy than is actually the case.

Discussion

 This form of communication was readily understandable by communication partners who had literacy skills and enabled the students to communicate effectively across a range of job-related and social activities.

 The picture dictionaries also appeared to be more motivating than symbol-based communication boards for these students, which may have contributed to their success.

Paper #3: Ganz et al, 2008

Generalization of a pictorial alternative communication system across instructors and distance. Ganz et al, 2008,

Augmentative and Alternative Communication

 Investigated use of a modified Picture Exchange Communication

System (PECS) protocol to teach AAC-supported functional communication skills to a 12-year-old boy with autism.

Introduction

 Nonverbal individuals with autism spectrum disorders (ASD) often require the use of picture-based, aided augmentative and alternative communication (AAC) systems.

 The Picture Exchange Communication System (PECS) (Bondy

& Frost, 1994) is a widely employed example of a picture-based, aided AAC system.

 Phases I and II

 During Phase I, the child is taught to exchange a picture with an adult to receive an item

 During Phase II, the child is taught to locate his or her communication book, remove a picture from it, and walk to the appropriate communicative partner.

 Improves functional communication skills, speech skills and play

How to increase the use and ease of use of

AAC systems

 (a) giving individuals choices about which AAC devices

(e.g., voice-output-communication-aids versus picture selection methods) they prefer

 (b) organizing pictures according to taxonomic categories

 (c) decreasing the physical effort or response efficiency required to use the AAC device

 (d) individualizing aspects and instruction of AAC use in terms of vocabulary, cognitive, and communication abilities; needs in varied environments; and motor skills

Generalization of AAC-supported communication skills

 (a) generalization of AAC use into community settings

 (b) generalization of AAC use from clinical to natural environments

 (c) use of video-based instruction to teach generalization of

AAC use (to fast-food restaurants)

 (d) generalization of writing skills to less structured activities in children who use AAC systems

 Little research has investigated the generalization of these devices to a variety of communicative partners and under a variety of conditions

Research questions

 (a) How quickly would the participant (a Ryan, 12-year-old youth with autism) generalize the use of a pictorial AAC system across three adult instructors when those instructors were more than 10 feet away (Phase

1)

 (b) Would the participant spontaneously generalize the use of his AAC system to a novel condition (communication binder 10 or more feet away and reinforcer within reach) when taught in a more complex condition (communication binder and reinforcer 10 or more feet away)

(Phase 2)

 (c) Once the participant had been instructed to use his communication device in a number of conditions in which he was able to reach his communication binder, would instruction be required or would the participant be able to spontaneously determine a method of communicating the need for help retrieving his communication binder and reinforcers when they were placed out-of-reach (Phase 3)?

Participant

Ryan was a 12-year-old boy with autism.

His vision, hearing, and fine and his gross motor skills within the normal range

 Could play independently for 10– 20 min with a preferred toy or activity

Ryan did not speak, but occasionally vocalized speech-like sounds.

He communicated primarily by pointing, using a few manual signs and approximations (e.g., CRACKER, DRINK)

 Ryan responded appropriately to several simple verbal and gestured commands, including Sit down, and, Get your chair.

Ryan was able to use voice-output AAC devices

He mastered the skill of picture correspondence; that is, matching numerous pictures with actual items.

Baseline: Phase 1

 Generalization across near and far instructors.

 Instructor A (the first author) stood near Ryan (i.e., within arms-reach),

 Instructor A stood far away from Ryan (10 feet or more away)

 Instructor B near

 Instructor B far

 Instructor C near (instructors varied),

 Instructor C far.

Baseline: Phase 2

 Generalization of picture exchanges when the participant’s

AAC device and preferred items were far

 Communication binder near Ryan and reinforcer near

 Communication binder near and reinforcer far (10 or more away)

 Communication binder far but within-view and reinforcer near

 Communication binder far, but within-view and in-reach and reinforcer far

Phase 3: Generalization

 To determine how the participant would spontaneously communicate the need for help when his communication binder and/or reinforcer was placed out-of-reach.

 Communication binder near (within arms-reach) and reinforcer far and out of reach

 Communication binder far (approximately 10 feet or more away) and reinforcer far and out-of-reach;

 Communication binder far and out-of-reach and reinforcer near

 Communication binder far, within-view but out-of-reach, and reinforcer far

 Communication binder far, however within-view and out-ofreach and reinforcer far, within- view but out-of-reach.

Results and Discussion

 Picture-based interventions provides a means for students with

ASD to spontaneously initiate their wants and needs while utilizing a pictorial representation of a preferred item.

 This study demonstrated that a second instructor may be excluded or used briefly, thus saving valuable resources.

 This study contradicts previous research that has found that children with autism often have difficulty generalizing communication skills to novel situations.

Effective instructional strategies in producing generalization of skills

 (a) training of sufficient exemplars, in which generalization instruction is planned in a variety of contexts with a variety of materials to ensure all possible variations are addressed;

 (b) teaching skills that will naturally be reinforced by others in community settings (e.g., the appropriate words to use to request toys from peers);

 (c) using common stimuli across a variety of contexts or settings, and

 (d) mediated generalization, in which instructors teach responses that will likely be required in a variety of contexts, thus promoting generalization in those other contexts

Two obstacle arise when using aided-AAC

 Learning to approach the appropriate listener:

 The appropriate listener was defined as the person holding the preferred item.

 Retrieving an inaccessible AAC device:

 Indicate to listeners that they need to obtain their AAC devices when they are not accessible. Ryan did this by using behavior indication

(e.g., reaching, leading)

Thank you.

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