A comparison of two approaches for representing AAC vocabulary for young children (summary)

Young Children


A significant percentage of children with special educational needs have complex communication needs and might benefit from the use of some form of augmentative and alternative communication (AAC) system.

It is important that these children are given early access to language and communication to enable them to express early communicative functions. Develop language concepts and build social relationships. This requires access to a wide range of vocabulary.

Vocabulary items range from very concrete to highly abstract, the latter being much more difficult to ‘experience’, for example concepts such as ‘more’ or ‘big’.

Young AAC users need access to a range of concrete and abstract linguistic concepts.

When using symbols for communication the user has to recognise the link between the picture or symbols and the concept it represents, and be able to use it in different situations to communicate different intentions. Concrete vocabulary is generally easy to represent in pictoral or symbol form, abstract concepts are more difficult and less ‘transparent’ with little obvious connection to the thing they represent.

Research has found that the transparency of graphic symbols effects the ability of typically developing young children to identify and learn symbols. Representations of concrete concepts e.g. object labels (nouns) are easier to learn than more abstract words such as verbs and adjectives.

Many AAC systems represent abstract concepts with symbols based on adult understanding of the word they represent, this understanding is not necessarily the same for children. This has been investigated by Janice Light and colleagues who asked typically developing children to draw 10 abstract early concepts and explain their drawings. There were great differences between these and other, commercially available symbol systems such as Picture Communication Symbols (PCS).

This study aimed to look into the ability of young children to identify symbols developed and designed using children’s understanding of the concepts represented, known as Developmentally Appropriate Symbols (DAS), compared with the commercially available PCS which are based on adult understanding of the concepts. Children’s preferences of the different symbol types were also investigated.


What did they do?

Forty typically developing pre-school children were randomly divided into two groups and the authors looked into the accuracy with which they identified symbols following a short period of training and which symbol set the children reported to prefer.

10 early concepts were used; all gone, big, come, eat, more, open, up, want, what and who. All were represented in PCS and DAS symbol sets.

Each child took part in one sessions during which they were shown one set of 10 symbols, either all DAS or all PCS, given the label for the symbols and an explanation of the relation between the idea/concept and the symbol.

The children were asked to look at all 10 symbols on a single sheet and identify each one when the name was given by the researcher.

Immediately after completion of the 10 identification trials the children were shown both sheets of 10 symbols together and asked which pictures they liked best and what they liked about the preferred set.


What did they find?

In the symbols identification task the children were 82% accurate with the DAS set and 58% with PCS. All items in the DAS group scored more highly except ‘who’ which was identified correctly by equal numbers of children in both groups.

The DAS symbols had consistently higher correct selections across all three word categories used; action words, descriptors and questions.

In choosing preferences for symbols sets there was no significant difference between the two, though higher numbers selected DAS.



It is suggested that it might be beneficial to use symbols developed taking children’s conceptual knowledge into account when introducing symbols based AAC to very young children, but these are acknowledged to be complex and difficult to create.

The concepts that were most difficult to represent in DAS were those that are used in a wide variety of contexts and so are challenging to represent in a single relevant picture.

The authors suggest that it is not easy to collect information on symbols preferences from very young children, possibly due to their understanding of the questions being asked; ’ Which pictures do you like better?’ and ‘Why?’. Understanding of these question forms tends to develop later than understanding of ‘What?’ and ‘Who?’ questions. Some children did not express a preference and more were unable to give a reason for their choice.



This study investigated typically developing children only, further research should include children with developmental disabilities.

The study also considered only a small number of concepts, possibly increasing the rate of learning and reducing errors. This did not realistically represent the amount of early vocabulary young children need and generally acquire.

The training given in the study was not typical of that used in introducing AAC. The way in which children need to use symbols to represent language in an AAC system is much more complex than simply identifying symbols in response to spoken labels.

Things you may want to look into:

Interpretation and Construction of Meaning of Bliss-words in Children

Teaching Conceptually Referenced Core Vocabulary for Initial Augmentative and Alternative Communication

The Iconicity of Picture Communication Symbols for Children with English Additional Language and Mild Intellectual Disability

Iconicity in the Development of Picture skills: Typical Development and Implications for Individuals with Severe Intellectual Disabilities

Added to site September 2016