There are two main sets of symbols available Widgit Literacy Symbols (WLS) from Widgit Software based in the UK and Pictorial Communication Symbols (PCS) from Mayer Johnson based in the US. Previously these two symbol sets have competed with one another but the two companies now appear to work closely and each set has a clearly defined role.
The recent change of name from 'Widgit Rebus' to 'Widgit Literacy' makes clear the new defined purpose of this symbol set. The vocabulary is extensive and at the time of writing reportedly covers over 30,000 words. These include grammatical symbols required for more accurate representation of text, such as putting verbs in the past and the future. The detail in the symbols is kept to an absolute minimum allowing them to read quickly and a variety of rules (see below) remains consistent throughout the set. Until recently these symbols were only available in black and white but Widgit created colour versions to coincide with the release of Communicate: In Print 2.
To make the symbols easier to understand Widgit have devised four 'levels' into which any symbols can be (approximately) categorised:
These symbols are usually recognisable to any reader as they clearly illustrate the object or action they represent.
These symbols are fairly abstract but follow strict rules allowing the meaning of any symbol to be guessed once the rules are learnt.
These symbols need to be taught as it is difficult to guess their intended meaning from the symbol alone. However many people with learning difficulties find these easier to remember than text alone.
How to you represent a word like 'is' in symbol form? These symbols are the most difficult to work with as they are purely abstract representations and are very difficult to recognise without being first taught the meaning. Some symbols, such as 'Sorry' below, are based on the action used in the BSL or Makaton sign languages.
These symbols are often not used in pieces of text except for the most advanced symbol-users.
The PCS symbol set was primarily designed for face-to-face communication and is used extensively by speech & language therapists for high tech and low tech communication aids. The pictures contain more detail making them aesthetically pleasing and motivating to use but as there only 10,000 words are covered in the set more obscure and grammatical words might not be covered.
DynaSyms is the proprietary symbol set used on the popular Dynavox range of communication aids. There are over 5,000 symbols in the DynaSym set but they can be combined to create more meanings such as the combination of 'bed' and 'idea' to create 'dream'. DynaSyms are available as an add-on for Boardmaker and conversely PCS Symbols can be installed on to DynaVox communication aids.
The Imagine Symbol set is a growing collection of symbols designed for augmentative and alternative communication (AAC). They are free for non-commercial use. Further information can be found at www.imaginesymbols.com .
The preceding information seems to make choosing a symbol set really simple: use WLS for literacy and PCS for communication. But be careful not to stick rigidly to that rule, however. It is up to a qualified professional such as a Speech & Language Therapist to look at each case individually and decide which is the optimum solution.
Obviously all symbol companies are very careful about retaining the copyright of their assets while allowing them to be used in a practical way. All symbols throught the Better Living Through Technology website are copyright of their respective owners. Further information about the allowed use of symbols can be found on the Widgit and Mayer-Johnson websites.
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