picture exchange communication system (pecs) by...

PICTURE EXCHANGE COMMUNICATION SYSTEM (PECS) –

REDUCING SELF-INJURIOUS BEHAVIOUR IN INDIVIDUALS WITH

AUTISM SPECTRUM DISORDER

By

SIMONE THERESA ELLEN BOURASSA

Integrated Studies Final Project Essay (MAIS 700)

submitted to Dr. Paul Kellogg

in partial fulfillment of the requirements for the degree of

Master of Arts – Integrated Studies

Athabasca, Alberta

April, 2014

Picture Exchange Communication System (PECS) – Reducing Self-Injurious Behaviour

in Individuals with Autism Spectrum Disorder.

ABSTRACT

Deficits in communication are characteristic of individuals with Autism spectrum

disorder and developmental disabilities. These deficits can impede their social

interaction, prevent inclusion in educational settings and inhibit their daily living skills.

An inability to communicate effectively with the environment can also predicate

challenging behaviour such as self-injury. These challenging behaviours can be

permanently physically damaging, socially inhibiting and continue through entire

lifetimes. Previous research has supported the use of strictly behaviour-based

interventions in reducing challenging behaviours. More recently research suggests that

challenging behaviour serves a communicative function, thus studies have begun to

explore the possibility of using speech and language-based interventions to reduce the

incidence of such behaviour. This study reviews the literature surrounding the

effectiveness of the applied behaviour analysis (ABA) based assessment tool, functional

behaviour assessment (FBA), in the reduction of self-injurious behaviour in autism. It

also reviews research which supports a language/communication-based intervention,

picture exchange communication system (PECS), for effectively reducing self-injurious

behaviour (SIB). The research question posed is: Is the use of Speech and Language

Pathology based intervention, the augmentative communication tool, picture exchange

communication system (PECS), effective in reducing the occurrence of self-injurious

behaviour in non-verbal individuals with Autism or developmental disabilities when used

in conjunction with the Applied Behaviour Analysis based Functional Behaviour

Assessment? The paper proposes an interdisciplinary approach, combining FBA with a

PECS intervention to successfully reduce self-injurious behaviour in individuals with

autism and developmental disabilities.

TABLE OF CONTENTS

Introduction ......................................................................................................................... 1 Literature Review............................................................................................................ 3

Behaviour Analysis Perspective ......................................................................................... 4 Speech and Language Perspective ...................................................................................... 6

Summary ......................................................................................................................... 9 Interdisciplinary Approach ........................................................................................... 12

Conclusion ........................................................................................................................ 13 References ......................................................................................................................... 15

Introduction

Many children diagnosed as being on the Autism Spectrum, struggle with

communication skills – skills which come naturally to neurologically typical children. It

is typical for this developmental disorder to be characterized by deficits in

communication both receptively and expressively. Poor communication skills are also

associated with challenging behaviour including self-injurious behaviour (SIB) (Park

2012). It is because of these delays in communication that the Picture Exchange

Communication System (PECS) has been developed (Bondy & Frost 2002).

Augmentative communication and devices such as the PECS system, the use of computer

programs, and Apple IPAD applications have often been used to assist with

communication for those on the Autism Spectrum. Often, augmentative communication

devices can reduce frustration and anxiety in the individual on the Autism Spectrum thus

resulting in less incidence of challenging behaviour (Weiss & Harris, 2001).

My practice as a behaviour consultant is based on the principles of Applied

Behaviour Analysis (ABA). When analysing challenging behaviour, ABA dictates that a

functional behaviour analysis (FBA) is required to determine the function of the

behaviour (Cooper et al, 2007). Typically, behaviours serve an escape or access function

whether it is for attention, sensory stimulation, preferred/un-preferred activities, and

tangible items or people (Cipani & Schock, 2007).

PECS-Reducing Self-Injury in Autism

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At a recent conference on autism, the key note speaker, Jo Lynn Mullins – a

Board Certified Behaviour Analyst at the Institute for Applied Behaviour Analysis of Los

Angeles – indicated that this standard FBA is missing a key component: the awareness

that challenging behaviour is always serving a communication function (Matson 2009).

This progressive take on a traditional assessment tool was confirmation of what I had

suspected in my practical work. ABA theory dictates that if the behaviour serves an

attention seeking function we must render the behaviour ineffective in achieving its

function. I understand and agree with the logic behind this theory and in most situations it

is effective and easy to implement. This is not the case with SIB. I have employed a

number of different interventions based in ABA some of which have been effective, some

of which have been less effective. I have noticed that often SIB is exhibited as a form of

communication in individuals who are non-verbal or have limited oral language skills. It

is for these reasons I pose the question: Is the use of SLP based intervention –

augmentative communication tools (PECS) – effective in reducing the occurrence of

self-injurious behaviour in non-verbal individuals with Autism or developmental

disabilities when used in conjunction with the Applied Behaviour Analysis-based

functional behaviour assessment? Can we solve a behavioural problem with a language

intervention? Is self-injurious behaviour really behavioural communication? In an

attempt to answer this question, this paper will provide a thorough literature review and

analysis of current research from both Applied Behaviour Analysis and Speech and

Language Pathology disciplines.


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Literature Review

There exists a wealth of literature and research surrounding the efficacy of the

PECS protocol to teach a functional communication system which can increase

communication and language acquisition in individuals with developmental disabilities,

intellectual disabilities, and Autism Spectrum Disorder (Ganz 2009, Bondy & Frost

2002). The effect of PECS on the reduction of challenging behaviour, such as self-injury,

is a field of limited empirical evidence and research (Ganz 2009, Frea 2001). Conversely,

the study of Functional Behaviour Assessment (FBA) in determining the maintaining

factors of challenging behaviour and self-injury is rich with empirical support (Iwata

1994, Cooper & Heron 2007, Cipani & Schock 2007, Radstaake 2013). In my

professional experience, the use of FBA alone (or other ABA based interventions for the

reduction of the challenging behaviour, self-injury) is not an effective method on its own

(Frea 2001, Durand 2001). The following is a review of current literature and research

from both the fields of Speech and Language Pathology (SLP) and Applied Behaviour

Analysis (ABA) which provide quantitative evidence showing a positive correlation

between the use of augmentative communication devices, and/or functional behaviour

assessment and the reduction of self-injurious behaviour in nonverbal individuals with

Autism or other developmental disabilities to support the combined use of FBA and

PECS in the effective reduction of challenging behaviour, specifically SIB. The literature

review will cover literature which examines the effectiveness of behavioural

interventions for reducing challenging behaviours, the use of interventions which stem

from the field of speech and language pathology, and those which combine the use of


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both behavioural and communication interventions, how they pertain to the proposed

study and support its significance.

Behaviour Analysis Perspective

The behaviourist perspective for dealing with challenging behaviour, such as self-

injury, maintains that a functional behaviour assessment is required to determine the

potential function that a behaviour is serving. Cooper & Heron (2007) propose it as the

preliminary assessment tool to be accessed when addressing problem behaviour, and

suggest that it is from the results of such an assessment that an appropriate behavioural

intervention will be developed. Cipani & Schock (2007) note that a functional

assessment typically yields four categories of perceived behaviour function: direct access,

socially mediated access, direct escape, and socially mediated escape. They go on to

describe behaviour function as the capacity of the behaviour to enable the individual to

get what he or she desires through immediate and unassisted access to an item, person, or

event; through access with the assistance of another person (e.g., Mother giving a child

the desired toy); through immediately and independently withdrawal of themselves from

a situation, from an item or a person; or through withdrawal of themselves via the

assistance of another person (e.g., a crying child being removed from a grocery store by a

parent). Cipani & Schock propose that the intervention to be implemented be based on

which perceived function the challenging behaviour is serving for the individual. Their

rationale for this is the concept that when the function of a behaviour is being reinforced,

the behaviour continues or increases. In order to decrease behaviour (according to applied

behaviour analysis) Cipani & Schock say that all reinforcement of the behaviour and its

function must stop. In other words, they are saying that by withdrawing reinforcement, or


5

preventing the behaviour from achieving its desired purpose the behaviour will no longer

be functional to the individual and thus, the individual will have no reason to engage in

the problem behaviour. Functional behaviour assessment has been proven to be an

effective tool in the evaluation of self-injurious behaviour. This tool can assist

professionals in ascertaining if the individual is more likely to engage in self-injury

during certain environmental conditions (Iwata et al., 1994). These authors suggest that

demand conditions (to escape a task or demand), play conditions when toys are not

present (to access toys), or conditions of social attention (to access, or escape attention)

can provide insight into what is reinforcing the behaviour and thus, recognition of what

behaviour to avoid reinforcing. Danov et.al. expand this concept outlining that

behavioural interventions based on the function of the problem behaviour, determined

through FBA, have been successful in their application to individuals with ASD

exhibiting SIB (Danov et.al. 2010). Danquah et. al. discuss strong evidence for

behavioural explanations in treating SIB (Danquah et.al. 2009). Much of the research

indicates that the cause of the challenging behaviour is best determined by completing a

FBA, which can allow for effective selection of an appropriate intervention (LaRue et. al.

2008)

Although the behaviour analysis perspective and functional assessment is

effective in determining the function of a behaviour according to the four categories

described by Cipani & Schock (2007), it does not explore specifically the potential

communicative function of self-injurious behaviour. However, Maurice & Green (1996)

suggest that determining the perceived function of a self-injurious behaviour through

functional behaviour assessment enables interventionists and those working with


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individuals on the Autism Spectrum to implement behaviour-based interventions which

are effective in the reduction of most problem behaviours including those which are self-

injurious.

Speech and Language Perspective

Augmentative communication systems have been examined as a potential

intervention for the reduction of problem behaviour (Durand & Merges, 2001; Charlop-

Chrisy, 2002). Durand and Merges demonstrate that the use of such systems, including

picture exchange communication system (PECS), are effective in the acquisition of

language for children with Autism and also in reducing problem behaviour. Charlop-

Chrisy, in a study focusing primarily on the acquisition of speech in play and academic

settings with the use of PECS as an augmentative communication system, showed that

ancillary gains associated with increases in social-communicative behaviours and

decreases in problem behaviours were achieved. While they did not implement PECS as

an intervention specifically to reduce the problem behaviour, the association is made that

problem behaviour can decrease by increasing communication.

The PECS system was developed by Bondy and Frost and presented in their book,

A picture’s worth: PECS and other visual communication strategies in autism (2002).

They explain how to develop and implement a PECS system as a means to increase

communication and language acquisition in children who are developmentally delayed in

this area. They outline their system as a speech and language tool to improve

communicative ability but do not identify PECS as a tool for reducing challenging

behaviour. Tincani (2004) compares sign language and PECS, both augmentative


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communication systems designed to improve a child’s ability to communicate, and

determines that both of these augmentative communication methods are effective.

Weiss and Harris (2001), in their text, Reaching out, joining in: Teaching social

skills to young children with autism, discuss the benefits of PECS and augmentative

communication systems for the integration of children with autism into social groups and

interaction with peers. They examine the advantages of having such a system in place to

assist children with autism to communicate effectively with others in their environment.

Weiss and Harris assert that the ability to communicate effectively can reduce isolation—

isolation which can lead to anxiety and stress. Further, they suggest that augmentative

communication systems, such as PECS, are useful in achieving reductions in isolation,

anxiety and stress. Since anxiety and stress can influence the occurrence of challenging

behaviours, including self-injurious behaviour.

Park et.al. (2012) investigate the relationship between language skills and

behaviour problems in pre-schoolers with autism. Their results demonstrate that there

was a relationship between receptive communication skills and the exhibition of

challenging behaviour. Indicating interventions targeting communication skills may lead

to a reduction in challenging behaviour.

A larger sample size study by Matson et. al. (2009) supports the findings of Park

et. al. (2012). Matson and colleagues’ results indicate lower levels of receptive

communication alone significantly correlated with higher levels of multiple topographies

of challenging behaviour, with SIB correlating highest, in children with Autism. The


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findings of both of these studies indicate that there is a communicative function of

challenging behaviour and SIB.

The use of PECS has been demonstrated to be effective in the reduction of

challenging behaviour of a child with Autism (Frea et. al. (2001). In this particular case

functional behaviour assessment was used, but it alone did not differentiate any clear

communicative functions of the behaviour. Despite this fact, PECS was introduced and

found to be effective in reducing the challenging behaviour. The results support the

proposition that enhanced communication needs to be a primary goal for individuals with

challenging behaviour.

When evaluating the effectiveness in reducing SIB two communicative response

modalities were compared in the Danov et. al (2010) study of a child with Autism. The

authors found that SIB was eliminated during functional communication training sessions

with the use of picture cards (PECS), not verbal speech. These results promote the use of

PECS over verbal speech prompting when implementing function communication

training to reduce SIB.

Durand & Merges (2001) identify the importance of adopting a communicative

metaphor as a model for problem behaviour in their single subject study of a child with

Autism who engaged in SIB. Prior to the study a number of behaviour based

interventions (DRI, time-out from positive reinforcement, restraint) had been used to

reduce the challenging behaviour, with no long-term success. The authors outline that

these behaviours are not simply responses which require reduction and elimination, but

that they can be in fact methods in which the individuals are attempting to communicate


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through behaviour. They suggest that attempting to eliminate challenging behaviours

through some reductive technique leaves the individuals without a means to communicate

needs and desires. Durand and Merges posit that other maladaptive behaviours also

known as “symptom substitution” or “response covariation” would be substituted for the

original challenging behaviours. In their study, the subject was taught to use an

augmentative communication device to communicate. As a result his SIB was reduced

dramatically.

Summary

A behavioural perspective maintains that functional behaviour assessment and

behavioural interventions are effective in the reduction of problem behaviour (Cooper &

Heron, 2007; Cipani & Schock, 2007; Danov et. al. 2010; Danquah et. al. 2009; LaRue

et. al. 2008; Iwata et al, 1994; Koegel et. al, 2009; Maurice & Green, 1996). A language

perspective maintains that augmentative communication strategies, such as PECS are

effective in increasing language and improving communication as well as reducing

challenging behaviour (Bondy & Frost 2002; Charlop-Christy et. al, 2002; Danov et. al,

2010; Durand & Merges 2001; Frea et. al. 2001; Koegel et. al 2009; Matson et. al. 2009;

Park et.al. 2012; Tincani 2004; Weiss & Harris 2001). These studies also indicate that

the ability to communicate effectively can reduce stress and anxiety, which potentially

can trigger problem behaviour. With increased capacity for communication as a result of

using an augmentative communication system, problem behaviours have been observed

to decrease (Charlop-Christy et. al, 2002; Danov et. al, 2010; Durand & Merges, 2001;

Frea et. al. 2001; Matson et. al. 2009; Park et.al. 2012; Weiss & Harris, 2001).


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Research is limited but growing surrounding preliminary assessment of

challenging behaviour using both Functional Behavioural Analysis and the

implementation of a communication-based intervention such as PECS. This

interdisciplinary approach of combining the elements of the ABA and SLP disciplines is

proving to have successful results in reducing challenging behaviour such as SIB,

although further research is needed.

LaRue et. al. (2008) discuss the role of speech and language pathologists and

behaviour analysts in serving individuals with autism via functional communication

training (FCT). In their review, the authors suggest a collaboration of the two professions

for an integrated approach which promotes comprehensive programming and quality of

services provided to individuals with Autism who exhibit challenging behaviour. They

discuss the use of FBA to determine the function of a behaviour thus allowing

practitioners to teach the learner to achieve the same reinforcement, previous attained by

challenging behaviour, using an adaptive form of communication (LaRue et. al. 2008).

They suggest that by first conducting an FBA, the communication response can be

matched to the function of the challenging behaviour (e.g. requests for attention, escape,

etc.).

In further support of the use of FBA in conjunction with a communication

intervention such as PECS in the reduction of challenging behaviours, is the research

presented on functional communication training by Durand & Merges (2001). In their

study an FBA was conducted initially for the subject with Autism who exhibited SIB.

Following the FBA the authors implemented an augmentative communication system to

provide the individual with a form of communication other than the demonstration of


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SIB. In this case SIB was reduced dramatically following the FBA and the

communication based intervention. The results of this study demonstrate the

effectiveness of an integrated SLP & ABA approach to challenging behaviour,

specifically SIB.

Any discussion of the implementation of a communication intervention in

conjunction with FBA of challenging behaviour raises the question of which form of

communication based intervention is best arises. The evaluation of two communication

modalities presented by Danov et. al. (2010) assists in answering this question. The

results of their study indicate that the use of a picture exchange based intervention

(similar to that of the PECS protocol) is more effective in the reduction of SIB than is a

verbal speech modality. Their research supports the use of a picture system over other

forms of communication interventions for reducing SIB in individuals with Autism.

In the research presented by Radsaake et. al. (2013), classroom teachers used

FBA procedures to identify the communicative functions of challenging behaviour

presented by three children with Angelman syndrome. PECS was introduced as an

intervention for SIB of one of the study subjects following the FBA. Results indicate that

the use of FBA to determine to communicative function of the challenging behaviour

combined with the PECS intervention was successful in significantly reducing the SIB.

This study provides additional support for the interdisciplinary approach of FBA used in

collaboration with PECS protocol as an intervention for SIB for individuals with

developmental and intellectual disabilities.


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Interdisciplinary Approach

This research comprises elements of two disciplines—speech and language and

behaviourism or applied behaviour analysis. It poses a behaviour question and proposes

a speech and language solution. How can we reduce self-injurious behaviour? That is a

behavioural question. Will PECS reduce this behaviour problem? That potential solution

stems from the field of speech and language rather than the applied behaviour analysis

aspect of behaviourism. Functional behaviour analysis is a tool embedded in Applied

Behaviour Analysis, the augmentative communication tool, PECS, finds its roots in the

field of speech and language.

Interdisciplinary research is defined as “any study or group of studies undertaken

by scholars from two or more distinct scientific disciplines. The research is based upon a

conceptual model that links or integrates theoretical frameworks from those disciplines,

uses study design and methodology that is not limited to any one field, and requires the

use of perspectives and skills of the involved disciplines throughout multiple phases of

the research process” (Aboela et.al. 2007). Since this paper draws from both the Speech

and Language Pathology discipline and the Applied Behaviour Analysis discipline, by

reviewing the use of an intervention from both (functional behaviour assessment and

augmentative communication tools) in combination as a new intervention for self-

injurious behaviour (which is typically managed with an intervention based in applied

behaviour analysis only) this research topic provides a useful base of information for

further research for the field of Interdisciplinary Studies.


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Conclusion

As outlined by LaRue et al. (2008) a significant and primary concern for

individuals with Autism and other developmental disabilities is the existence of

significant communication deficits, which place these individuals at risk for poor

outcomes such as maladaptive or challenging behaviour. Specifically self-injurious

behaviour is of particular concern as it can interfere with academic and social integration

as well as cause serious permanent physical harm. If these behaviours are not assessed

and the appropriate intervention is not implemented they can escalate and continue

throughout a lifetime (Danquah et. al. 2009). As demonstrated through the literature

review there exists significant evidence to support the use of an interdisciplinary

approach to managing and reducing self-injurious behaviour in individuals with autism

and developmental disabilities. As presented in much of the literature the effectiveness of

FBA alone has not proven as effective in reducing challenging behaviours as previously

thought. In fact, these behaviours are often exhibited as a form of communication. By

analyzing the potential function of such behaviours with FBA, professionals can target

specific communication modalities to replace the communicative function of the

challenging behaviour. This is a new form of intervention appears to be more effective

than the behaviour based interventions such as differential reinforcement, time-out from

reinforcement, etc. which have been considered to be most effective in addressing SIB.

As the field of interdisciplinary studies grows, specifically with respect to this research,

the quality of service and effectiveness of interventions specific to individuals with

autism or developmental disabilities will also grow and improve.


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Much research is needed in the expansion of the interdisciplinary ideas proposed

in this paper. Many of the studies presented had small sample sizes, and not all the

behaviours evaluated were specifically self-injurious. This decreases the validity of the

research results relative to the question posed in this research paper. It is suggested that

future research with a specific focus on the mitigation of self-injurious behaviour might

prove valuable to both disciplines. However it must be said that the potential of this new

and growing interdisciplinary field of research presents encouraging preliminary results

for families of individuals with autism or developmental disabilities who engage in self-

injurious behaviour, the individuals themselves, the disciplines of speech and language

pathology and applied behaviour analysis, the practitioners who work within each field,

and educators and service providers who work directly with those individuals.


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References

Aboelela, S. W., Larson, E., Bakken, S., Carrasquillo, O., Formicola, A., Glied, S. A.,

Haas, J. and Gebbie, K. M. (2007), Defining Interdisciplinary Research:

Conclusions from a Critical Review of the Literature. Health Services Research,

42: 329–346. doi: 10.1111/j.1475-6773.2006.00621.x

Bondy, A., & Frost, L. (2002). A picture’s worth: PECS and other visual communication

strategies in autism. Bethesda, MD: Woodbine House, Inc.

Charlop-Christy, M.H., Carpenter, M., Le, L., LeBlanc, L.A., & Kellet, K. (2002) Using

the picture exchange Communication system (PECS) with children with autism:

Assessment of PECS acquisition, speech, social-communicative behavior, and

problem behavior. Journal of Applied Behavior Analysis, 35, 213-231

Cipani, E., & Schock, K.M. (2007). Functional Behavioral Assessment, diagnosis, and

treatment: A Complete system for education and mental health settings. New

York, NY: Springer Publishing Co., LLC.

Cooper, J. O., Heron, T. E., & Heward, W. L. (2007). Applied behavior analysis (2nd

ed.).

Upper Saddle River, NJ: Pearson Education, Inc.

Danquah, A., Limb, K., Chapman, M., Burke, C., Flood, A., Gore, S., Greenwood, K.,

Healey, K., Reid, W.K., Kilroy, J., Huma, L., Malone, C., Perkin, M., Hare, D.J.

(2009) An Investigation of the Factors Predictive of Continued Self-Injurious

Behaviour in an Intellectual Disability Service. Journal of Applied Research in

Intellectual Disabilities, 22, 395-399.

Danvo, S.E., Hartman, E., McComas, J.J., Symons, F.J. (2010) Evaluation of Two

Communicative Response Modalities for a Child with Autism and Self-Injury.

Journal of Speech and Language Pathology and Applied Behavior Analysis, 5(1),

70-79.

Durand, M.V., & Merges, E. (2001). Functional communication training: A

contemporary behavior analytic intervention for problem behaviours. Focus on

Autism and Other Developmental Disabilities, 16(2), 110-119, 136.

Frea, W.D., Arnold, C.L., Vittimberga, G.L. (2001). A Demonstration of the Effects of

Augmentative Communication on the Extreme Aggressive Behavior of a Child

with Autism Within an Integrated Preschool Setting. Journal of Positive Behavior

Interventions, 3(194), 194-198.

Ganz, J.B., Parker, R., Benson, J. (2009) Impact of the Picture Exchange Communication

System: Effects on Communication and Collateral Effects on Maladaptive

Behaviors. Augmentative and Alternative Communication, 25(4), 250-261.


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Iwata, B.A., Dorsey, M.F., Slifer, K. J., Bauman, K. E., & Richman, G.S. (1994) Toward

a functional analysis of self-injury. Journal of Applied Behavior Analysis, 27,

197-209.

Koegel, L. K., Koegel, R. L., & Dunlap, G. (Eds.). (2009). Positive behavioral support:

Including people with difficult behavior in the community. York, PA : The Maple

Press Co.

Radstaake, M., Didden, R., Lang, R., O’Reilly, M., Sigafoos, J., Lancioni, G.E., Appels,

N., Curfs, L.M.G. (2013) Functional Analysis and Functional Communication

Training in the Classroom for Three Children with Angelman Syndrome. Journal

of Developmental and Physical Disabilities, 25, 49-63

LaRue, R., Weiss, M.J., & Cable, M.K. (2008) Functional Communication Training: The

Role of Speech Pathologists and Behavior Analysts in Serving Students with

Autism. Journal of Speech-Language Pathology and Applied Behavior Analysis,

3(2), 26-34.

Matson, J.L., Boisjoli, J., Mahan, S. (2009) The Relation of Communication and

Challenging Behaviors in Infants and Toddlers with Autism Spectrum Disorders.

Journal of Developmental and Physical Disabilities, 21, 253-261.

Maurice, C., Green, G., & Luce, S.C.(Eds.). (1996). Behavioral intervention for young

children with autism: A manual for parents and professionals. Austin, TX: PRO-

ED, Inc.

Park, C.J., Yelland, G.W., Taffle, J.R., Gray, K.M. (2012) Brief Report: The

Relationship Between Language Skills, Adaptive Behavior, and Emotional and

Behavior Problems, in Pre-schoolers with Autism. Journal of Autism and

Developmental Disorders, 42, 2761-2766.

Tincani, M. (2004). Comparing the picture exchange communication system and sign

language training for children with autism. Focus on Autism and Other

Developmental Disabilities, 19(3), 152-163.

Weiss, M. J., & Harris, S. L. (2001). Reaching out, joining in: Teaching social skills to

young children with autism. Bethesda, MD: Woodbine House, Inc


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Keywords

Autism spectrum disorder, Self-injurious behaviour, Picture exchange communication

system, Speech and language, applied behaviour analysis, functional behaviour analysis

picture exchange communication system (pecs) by...

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