Program. PECS (cont.) Speech-Generating Devices (SGDs) SGDs (Cont.) 11/19/2010. Wendt, Boesch, & Subramanian ASHA Convention 2010

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1 Annual Convention of the American Speech-Language-Hearing Association Moving from PECS to SGDs in AAC Intervention for Autism Oliver Wendt Miriam Boesch Anu Subramanian Ning Hsu Katie Johnstone Program Brief Overview: PECS and SGDs Research Question: how can we move learners with autism from PECS to an SGD? Current Experiment A Modified PECS Protocol to Infuse Speech Output Preliminary Results Study Limitations Future Research Directions Discussion/Questions and Answers The Picture Exchange Communication System (PECS) Structured behavioral intervention program to teach use of visual-graphic symbols for communication (Bondy & Frost, 1994) Exchanged-based (versus selection-based) graphic symbol strategy: initially teaches to make requests by handing/ exchanging symbols for desired items Later targets more spontaneous communicative acts Often the initial choice for starting AAC intervention in learners with autism who have little or nor functional speech for several reasons: PECS (cont.) It requires very few prerequisites only prerequisite is that the individual can clearly indicate what he or she wants Requesting often been targeted in early instruction of individuals with developmental disabilities due to motivational considerations (Reichle & Sigafoos, 1991) Later PECS phases systematically target spontaneous communication acts, a particular deficit in autism PECS graphic symbols are highly iconic (Preston & Carter, 9) Speech-Generating Devices (SGDs) Portable, computerized devices producing synthetic/digitized speech output when activated Graphic symbols are used to represent messages, activated by finger, switch, headstick, etc., selecting a symbol from the display Advantages over non-electronic systems due to providing additional auditory stimuli for the learner via speech output: SGDs (Cont.) Additional provision of speech output presented as (a) antecedent auditory stimuli (a.k.a. augmented input ), and/or (b) consequence auditory stimuli (a.k.a. feedback ) may benefit learners with developmental disabilities Gains in receptive and expressive language skills in adolescents with intellectual disabilities using SGDs (Romski & Sevcik, 1993, 1996) SGD may allow more independent form of communication (voice output understood by variety of familiar and unfamiliar comm. partners) 1

2 Research Questions Practitioners/parents: after successful mastery of (initial) PECS phases, can the child move on to a SGD? (Grether, 7) research into innovations to the PECS protocol is a laudable direction and should be continued using rigorous methodologies (Schlosser & Wendt, 8) Project goals: - Modify traditional PECS protocol for implementation and transition to an SGD - Evaluate the effects of such a modified PECS protocol on increasing requesting skills, social-communicative behaviors, and emerging speech - Evaluate effectiveness of a particular device for such purpose that is built upon PECS principles Experimental Design Multiple Baseline Design across participants (Baer, Wolf, & Risley, 1968) Intervention phase split into PECS phases and SGD phases, followed by maintenance phase Dependent measures: Requesting skills: number of correct requests during -trials session Social-communicative behavior: number of responses including eye contact, physical orientation towards comm. partner, positive affect via smiling/laughter Emerging speech: word vocalizations or word approx. Materials and Setting Traditional PECS book with PCS symbols for desired items Proxtalker - sentence strip that actually speaks : picture card is put on ProxTalker display speak out the symbol referent in form of prerecorded digitized speech - several picture cards can be combined to speak sentences - symbols used were identical to PECS symbols Departmental Speech Clinic, 3 sessions per week Reliability Second, independent observer (trained graduate student) scoring baseline and training session on all dependent measures Treatment integrity (TI) checklist to ensure correct protocol implementation All trainers took official PECS Basic Training Workshop, some team members prior experience with PECS Each phase for PECS and the ProxTalker had a distinct checklist according to the different phases outlined in the modified PECS protocol Trainer 1 and Trainer 2 are monitored separately, different components of the TI checklist for each 2

3 Participant Characteristics Baseline Video Clip Participant Age Gender Dx Communication Skills Subject A 9 male severe autism limited speech word approximations; some PECS exposure; gestures Subject Q 11 male severe autism mainly nonverbal with minimal word approximations; PECS exposure; gestures Subject J 11 male severe autism nonverbal; minimal PECS exposure; gestures Traditional PECS Protocol (Bondy & Frost,1994) (Preference Assessment) Phase I: Physical Exchange Phase II: Expanding Spontaneity SGD Implementation Phase III: Picture Discrimination Phase IV: Sentence Structure Phase V: Responding to What do you want? Phase VI: Responsive and Spontaneous Commenting Preference Assessment Parent interview to develop a list of potential reinforcers for further validation 6-8 food items were chosen from the list based on their general accessibility as the potential reinforcers Trial-based assessment was implemented to determine 4- reinforcers of equal value Preference Assessment (cont.) Specific Procedures: 1. A plate containing 1 potential reinforcer was presented in front of the participant 2. The participant had seconds to decide if he wanted to select the item 3. After the decision was made or after the participant finished eating the item, a 2 nd item was presented 4. Each item was offered times in a counterbalanced order. The participant had to take the item from the plate and eat the item in order to count as a selection 6. According to previous research (Pace et al., 198), items selected above 8% (4 out of times) were considered to be reinforcers PECS Protocol: Phase I This is an early learning period where the child will use a single picture The child will be prompted to pick up the picture, reach to the communicative partner, and release the picture into the partner s open hand The communicative partner will then give the desired item to the child who is allowed to play/eat the item for several seconds 3

4 PECS Protocol: Phase I Specific Procedures: A 1. The child will be enticed with a preferred item 2. As the child reaches for the desired item, the physical partner (trainer 2) will physically prompt the child to pick up the picture card and hand it to the communicative partner (trainer 1) 3. Trainer 1 will provide a visual cue by opening her hand 4. Trainer 2 will provide physical assistance using errorless learning procedures (backward chaining). Trainer 1 will comment on the request (e.g., cookie ) upon receiving the card and provide the child with the preferred item within seconds 6. Up to -second break will be given to consume the snack or play with the selected item Mastery criterion: Child exchanges a picture for 2 consecutive trials PECS Protocol: Phase I (cont.) Specific Procedures: B 1. Trainer 2 will gradually fade out, and trainer 1 will gradually fade the open hand cue by waiting increasingly longer to show the hand Mastery criterion: Child independently exchanges a picture for 2 consecutive trials Overall phase criterion: 8% accuracy for 2 consecutive sessions across 2 communicative partners and 3 reinforcers Training is repeated for trials with a variety of reinforcers. The targeted outcome is to have the child see a desired item, pick up a picture card, reach toward the communicative partner, and put the picture in her hand to obtain the desired item PECS Phase I Video Clip Beginning PECS Phase I Video Clip End PECS Protocol: Phase II The main component in communicative spontaneity is that the child will persist when no reaction to the initial attempt is given The child will learn to reach farther or to walk to the communicative partner PECS Protocol: Phase II Specific Procedures: A1 1. The picture card / PECS book will be placed in front of the child 2. Trainer 1 will entice the child with a preferred item from halfway across the room 3. If the child reaches for the item, trainer 2 will use backwards chaining as needed to assist the child in retrieving the picture card and giving it to trainer 1 Mastery criterion: Child independently travels to trainer 1 from halfway across the room to exchange a picture for 2 consecutive trials 4

5 PECS Protocol: Phase II (cont.) Specific Procedures: A2 1. The child will have to travel the full distance of the room to exchange the picture with trainer 1 Mastery criterion: Child independently travels to trainer 1 from across the full distance of the room to exchange a picture for 2 consecutive trials PECS Protocol: Phase II (cont.) Specific Procedures: B1 1. The distance between the child and card/pecs book will increase to half the distance from the room with trainer 1 situated next to the child Mastery criterion: Child independently retrieves the picture, walks back to trainer 1, and releases the picture onto the trainer s hand for 2 consecutive trials PECS Protocol: Phase II (cont.) Specific Procedures: B2 1. The distance between the child, the card/pecs book, and trainer 1 will increase to the full distance of the room Mastery criterion: Child independently exchanges a picture at full distance with trainer 1for 2 consecutive trials PECS Protocol: Phase II (cont.) Specific Procedures: C 1. Trainer 1 will be unavailable during the child s first picture exchange attempt (will engage in conversation with someone else, avoid eye contact, or turn back towards child) Mastery criterion: Child independently persists to exchange a picture at any distance for 2 consecutive trials Overall phase criterion: 8% accuracy for 2 consecutive sessions across 2 communicative partners and 3 reinforcers One goal is to have the child seek out the communicative partner when he or she is not in the room. Additional prompts, such as expectant looks, gestural cues, or eye gazes must be eliminated to enhance spontaneity. This should be done in different environments, with different trainers, across different activities, and with variety of reinforcing items *At the end of this phase, the PECS book is eliminated PECS Phase II Video Clip Beginning PECS Phase II Video Clip Middle

6 PECS Phase II Video Clip End ProxTalker Protocol: Phase II After the child completes the traditional PECS training for this phase, ProxTalker device training will be introduced A similar protocol will be followed but appropriate modifications will be used ProxTalker Protocol: Phase II ProxTalker Activation Specific Procedures: D1 1. The ProxTalker device (with a picture card on the button) will be placed in front of the child 2. Trainer 1 will entice the child with a preferred item from across the table 3. If the child reaches for the item, trainer 2 will use backwards chaining as needed to assist the child to activate the picture card Mastery criterion: Child independently activates the device while seated across from trainer 1 for 2 consecutive trials Specific Procedures: D2 1. The device (with a picture card on the ProxTalker book) will be placed in front of the child 2. Trainer 1 will entice the child with a preferred item from across the table 3. If the child reaches for the item, trainer 2 will prompt the child to grab the picture, place it on the button, and activate it Mastery criterion: Child independently grabs the picture and activates it with 8% accuracy for 2 consecutive sessions across 2 communicative partners and 3 reinforcers Expanding ProxTalker Spontaneity Specific Procedures: E1 1. The device will be placed in front of the child 2. Trainer 1 will entice the child with a preferred item from halfway across the room 3. If the child reaches for the item, trainer 2 will use backwards chaining as needed to assist the child to travel with the device to within arm s reach of trainer 1 and activate the picture card Mastery criterion: Child independently grabs the device, travels to trainer 1 from halfway across the room and activates the device for 2 consecutive trials Specific Procedures: E2 1. The child will have to travel the full distance of the room with the device and activate it near trainer 1 Mastery criterion: Child independently travels to trainer 1 from across the full distance of the room and activates the device for 2 consecutive trials 6

7 Specific Procedures: F1 1. The distance between the child and the device will increase to half the distance of the room with trainer 1 situated next to the child 2. The child will be prompted to retrieve the device, return to trainer 1 and activate it Mastery criterion: Child independently retrieves the device and activates it near trainer 1 for 2 consecutive trials Specific Procedures: F2 1. The distance between the child, the device, and trainer 1 will increase to the full distance of the room Mastery criterion: Child independently travels the full distance and activates the device near trainer 1 for 2 consecutive trials Specific Procedures: G 1. Trainer 1 will be unavailable during the child s first device activation (will engage in conversation with someone else, avoid eye contact, or turn back towards child) Mastery criterion: Child independently persists to communicate by activating the device twice at any distance for 2 consecutive trials Overall phase criterion: 8% correct for 2 consecutive sessions across 2 communicative partners and 3 reinforcers Generalization across communication partners should be sought. Preferred items will be provided with each correct request from the child. Incorrect requests will result in correct modeling/prompting by trainer 2 and verbal praise from trainer 1 after the correct steps are performed ProxTalker Phase II Video Clip Beginning ProxTalker Protocol: Phase III Discrimination preferred vs. distracter Specific Procedures: A 1. The child will be enticed with a preferred item and distracter item 2. If the child reaches towards the preferred item, trainer 1 will provide immediate verbal feedback (e.g., that s right ) 3. If the child reaches for the distracter picture, no social feedback is provided 4. Upon activation of the distracter picture, trainer 1 will provide the item ProxTalker Protocol: Phase III (cont.) Discrimination preferred vs. distracter Specific Procedures: A. If the child reacts negatively when provided with the item, trainer 1 will use a 4-step error correction for selecting the preferred item Mastery criterion: Child selects the desired picture card from the book, places it on the device, and activates it for 2 consecutive trials. Trainer 1 will rearrange the position of the picture cards prior to beginning the next trial 7

8 Number of Verbalizations Number of Requests Number of Social-Communicative Interactions ProxTalker Protocol: Phase III (cont.) Discrimination Two preferred items Specific Procedures: B 1. After the child makes a selection via the device, trainer 1 will do a correspondence check by verbally prompting the child to take the item ( Go ahead and take it ) 2. If the child reaches for the item that was not requested, trainer 1 will block access to the item and the 4-step error correction procedures will be implemented Mastery criterion: Child activates the picture that corresponds to the item selected for 2 consecutive trials ProxTalker Protocol: Phase III (cont.) Discrimination Two preferred items Specific Procedures: C 1. Three preferred items will be placed within the child s line of vision 2. The child will be prompted to make a request 3. Follow similar procedures from the previous subphase B 4. Trainer 1 will provide the reinforcer within seconds of the child correctly requesting it Mastery criterion: Child selects the desired picture card, places it on the device, and activates it for 2 consecutive trials Overall phase criterion: 8% correct for 2 consecutive sessions across 2 communicative partners and 3 reinforcers 2 Baseline PECS 1 PECS 2 Prox 2 A 4 Baseline PECS 1 PECS 2 Prox 2 A Effects on Requesting Skills 1 2 Q Effects on Social- Communicative Behavior Q J J Session Session 2 Baseline PECS 1 PECS 2 Prox 2 A Effects on Emerging Speech Q J Study Limitations Current protocol modifications end at PECS equivalent phase 3 Generalization established across intervention agents (different trainers) but not across learning environments Technically, design allows to demonstrate effects of PECS-ProxTalker combination but not of ProxTalker alone 1 Session 8

9 Future Research Directions Replication with younger participants How early in age can transition to SGD occur? Ongoing effects in later PECS equivalent phases What type of participant is a good candidate for transition, which one is not? Once a mid technology device such as the ProxTalker is mastered, what comes next? Potential trajectory of moving along an intervention spectrum: PECS (low tech) ProxTalker (mid tech)?(high tech) If speech is the focus: augmented input Future Research Directions (cont.) Can you start directly teaching the ProxTalker or similar SGD within a PECS-like protocol? Comparative Efficacy Research Study underway: PECS vs. ProxTalker Participants nonverbal children with autism no prior exposure to PECS Design multiple baseline across participants w/ embedded alternating treatment design Acknowledgements Questions??? This project is supported by a Project Development Team within the ICTSI NIH/NCRR Grant Number RR2761 Thanks to ProxTalker.com, LLC for providing devices Thanks to the families who agreed to participate in our research Contact Information Oliver Wendt, Ph.D. olli@purdue.edu Miriam Boesch, M.S. mchacon@purdue.edu Anu Subramanian, Ph.D., CCC-SLP subramaa@purdue.edu Purdue University West Lafayette, IN , USA Disclosure Statement The authors have no financial or nonfinancial interest in any organization whose products or services are described, reviewed, evaluated or compared in the presentation. 9

10 References Baer, D. M., Wolf, M. M., & Risley, T. R. (1968). Some current dimensions of applied behavior analysis. Journal of Applied Behavior Analysis, 1, Bondy, A., & Frost, L. (1994). The Picture Exchange Communication System. Focus on Autistic Behavior, 9, Grether, S. (7, November). Moving children with autism from PECS to a SGD. Paper presented at the Annual Convention of the American Speech-Language-Hearing Association, Boston, MA. Pace, G.M., Ivancic, M.T., Edwards, G.L., Iwata, B.A., & Page, T.J. (198). Assessment of stimulus preference and reinforcer value with profoundly retarded individuals. Journal of Applied Behavior Analysis, 18, Preston, D., & Carter, M. (9). A review of the efficacy of the Picture Exchange Communication System intervention. Journal of Autism and Developmental Disorders. DOI.7/s y References (cont.) Reichle, J., & Sigafoos, J. (1991). Establishing an initial repertoire of requesting. In J. Reichle, J. York, & J. Sigafoos (Eds.), Implementing augmentative and alternative communication: Strategies for learners with severe disabilities (pp ). Baltimore: Paul H. Brookes. Romski, M., & Sevcik, R. A. (1993). Language comprehension: Considerations for Augmentative and Alternative Communication. Augmentative and Alternative Communication, 9, Romski, M., & Sevcik, R. A. (1996). Breaking the speech barrier: Language development through augmented means. Baltimore: Brookes. Schlosser, R.W., & Wendt, O. (8). Augmentative and alternative communication intervention for children with autism: A systematic review. In J.K. Luiselli, D.C. Russo, & W.P. Christian (Eds.), Effective Practices for Children with Autism: Educational and Behavior Support Interventions that Work (pp ). Oxford, UK: Oxford University Press.