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Voice Output Communication Aids (VOCAs)


Voice Output Communication Aids (VOCAs) are devices used by individuals who are either unable to speak or whose speech in unintelligible. There is a wide range of VOCAs commercially available. The most important element concerning these devices is that they reflect as closely as possible, the users own abilities and that they fulfil the needs of the user.

What is the difference between a dedicated device and a communication software programme?

Dedicated Communication Devices

Dedicated communication devices are designed specifically with communication as their primary goal, although recent advances in infra-red and bluetooth technologies have led to the incorporation of environmental control options being added in an increasing number of cases.

They are available with both text-based and symbol-based programmes, and many are wheelchair mountable.Typically they will store frequently used words or phrases in memory that can be accessed by a two or three key combination. For example UB = “I need to use the bathroom, please.

They typically include a ‘Word Prediction Facility’ as standard. This is a very useful tool as it significantly reduces the number of keystrokes a user has to make.

Symbol based communication devices are commonly used by individuals whose literacy skills prevent them from accessing a text-based system. However, there is a range of symbol-based language representation systems, called Minspeak, which require the user to learn a specific symbol coding system so that symbols can be used individually or in combination to communicate. Sometimes this offers a more efficient method of communication than using text, even for highly literate users.

Other symbol based communication devices are much simpler, and allow the user to decide which symbol is associated with which word. These symbols can then be used to store single words, phrases or entire sentences, depending on the user’s abilities.

Below are two examples of  symbol based dedicated communication devices:

symbol based dedicated communication device

Below are two examples of dedicated Text to Speech devices:

Text to Speech deviceSecond Text to Speech device

PC – Based Communication Software Programmes

PC – Based Communication Software Programmes

In recent years, a wide number of manufacturers have developed software programmes which can be installed on to a standard Windows computer.

Communication software programmes come in a range of styles, and vary in complexity. Some are largely 'content-free', and allow the user and his/her family/carers to programme words and messages to suit the user’s specific requirements. Others come with templates consisting of vocabulary sets which enable the user to communicate straight away, without the need for immediate programming. However, all software should be customised to meet the user’s needs, and should be updated on a regular basis as the user’s needs change and expand.

As with dedicated devices, communication software programmes can be text-based or symbol-based.