Autism is a spectrum disorder that typically involves communication difficulties.

The Picture Exchange Communication System (PECS) is an alternative and augmentative form of communication that uses pictures to improve communication skills. Initially designed to aid autistic children with extremely limited functional speech or those who were completely nonverbal, PECS can be more widely used today to improve communication in autistic individuals overall.

PECS is an evidence-based treatment method that is recommended to improve functional communication skills in people with autism spectrum disorder (ASD).

What Is PECS?

The Picture Exchange Communication System (PECS) was designed in the mid-1980s based on the principles of applied behavior analysis (ABA) therapy. It was first implemented at the Delaware Autistic Program (DAP) for nonverbal preschool autistic children.

PECS is designed as a form of positive reinforcement. The child shows a picture and gets what they are asking for. It can build up from single pictures to more advanced phases that can include complete sentences.

Ultimately, PECS can help to improve communication and social engagement with peers. It is typically used as an adjunctive therapy type. This means that it is used in conjunction with other forms of therapy and treatment.

PECS can be used in the classroom and at home to help children communicate requests and thoughts — anything that can be depicted by a picture. A child will have communication pictures that they can produce when they have specific needs, wants, feelings, or thoughts to help indicate what they are thinking or feeling.

This system helps to reduce tantrums that are often the result of unmet needs. Over time, the child will experience less frustration, as their ability to communicate is boosted.

PECS has been proven effective for children between the ages of 3 and 12. It can be useful for improving cognitive and physical communication issues in adolescents and adults with autism as well.

The 6 Phases of PECS

The Picture Exchange Communication System is meant to improve functional communication by developing a self-initiating system involving pictures instead of verbal cues. There are six phases of PECS.

Phase 1: How to Communicate

Pictures are used in exchange for what the person really needs or wants.

Phase 2: Distance & Persistence

Single pictures are used to teach persistent communication across a variety of settings and with different people to generalize the new skill.

Phase 3: Picture Discrimination

A PECS Communication Book is designed, which is a three-ring binder to store pictures that can be easily removed and used to communicate. Two or three pictures are now used to ask for specific things.

Phase 4: Sentence Structure

A detachable sentence strip is used to form simple sentences beginning with “I want” and followed by subsequent pictures.

Phase 5: Responsive Requesting

Pictures are used to answer questions such as, “What do you want?”

Phase 6: Commenting

Pictures are used to respond to questions and also for the person to make up their own sentences. Adjectives, conjunctions, and verbs can be added to the sentences in the more advanced phases. The six phases of PECS build on each other to form a complete form of communication.

How PECS Is Used for Autism

PECS differs from traditional autism therapies in that it uses pictures instead of words. In this way, it can be less intimidating and help to improve independence as well as social and functional communication. With autism treatment, PECS is used simultaneously with other therapies too, such as ABA therapy.

The Picture Exchange Communication System is a form of augmentative and alternative communication (AAC) that is low-tech. As a result, it’s less expensive than many other methods of AAC, such as those requiring technological devices.

It should be initiated by a trained professional to be the most effective. In the first phase, children will work with their communication partner directly.

Phase 2 requires that the child travel to use their pictures to make their requests and communicate with different people. Peers in a classroom or small group setting can be taught how to respond and use PECS to communicate together. It can also be used at home and in therapy sessions.

With phase 3, children learn to use picture symbols to discriminate between things they want and do not want. Phase 4 includes the use of the sentence strip to ask for things that are present as well as things that are not present.

During phase 5, the child will learn how to use the sentence strip and pictures to respond directly to adult questions. Phase 6 is used to expand upon this and improve vocabulary.

Once PECS is taught, it can and should be supported in all environments, and its use can be improved and expanded at home. The PECS Communication Book is designed to be portable, so the individual can take it with them wherever they go.

PECS & ABA Therapy

The Picture Exchange Communication System is based on the methodology used in ABA — positive reinforcement to help modify behaviors.

ABA is considered one of the top evidence-based treatment methods for autism. It is scientifically proven to be effective in improving outcomes for autistic children when used intensively long term. One of the benefits of ABA is that it is highly adaptable and can be tailored to fit the individual.

When ABA is used as a flexible behavioral therapy, PECS can also be included as part of the treatment program. Both approaches can complement each other.

The Pros & Cons of PECS

There are limited studies on the effectiveness of PECS; however, the studies that do exist indicate that it can be improve long-term social communication skills in nonverbal autistic children. Initial controversy surrounding PECS was that it would hinder the potential for verbal skills, but the opposite is likely true.

Sign language is often chosen before PECS as a form of nonverbal communication. This is because there are limitations to using pictures since you must have a picture to depict each possible thing. Studies have shown that PECS can be as effective, if not more, in improving communication in nonverbal autistic children, however.

The Picture Exchange Communication System can help to minimize problem behaviors associated with autism, such as poor communication skills and repetitive behaviors, like hand flapping and head turning, by as much as 60%. When a child is more able to communicate effectively, they are less likely to engage in problem behaviors, and they have fewer emotional outbursts as a result.

Overall, PECS is a low-cost form of complementary therapy. It can be beneficial when used as part of a complete treatment plan for autism.


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