Page 210 - Handbook of Electronic Assistive Technology

198 HANDBOOK OF ELECTRONIC ASSISTIVE TECHNOLOGY

circumstances or settings. With reference to adequacy ‘Communicative competence
suggests an adequate level of communication skills to function within the environ-
ment; it does not imply total mastery of the art of communication’ (Light, 1989). This
leads us away from the expectation that people who use AAC must be perfect in terms
of expression (e.g., by using complex grammatical formulations), or perfect in terms of
speed (e.g., being able to generate words at a speech rate observed in non-AAC users).
In other words, professionals should use benchmarks that are not just based on nor-
mal spoken communication. Sufficiency of knowledge, judgement and skill is what
matters rather than total mastery.
Light identifies four areas of competency that underpin performance in AAC system
use: linguistic, operational, social and strategic. Each of these interdependent areas is a
vital component of communicative competence in AAC use.

Linguistic Competence

This refers to an adequate mastery of the linguistic code. For AAC users there are two com-
ponents: being able to communicate using an AAC code (e.g., symbols) and being able
to understand the native language(s) (e.g., spoken English). Light argues that functional
communication without this level of competence is possible but severely limited. In bi- or
multilingual environments the linguistic demands are clearly greater. It is important to
note that some people using AAC may only have access to a limited vocabulary set and this
in itself may limit their linguistic competence.

Operational Competence

This refers to the technical skills required to operate a system. These are not just motor
abilities such as competent switch operation but also sensory abilities (e.g., vision) and
cognitive abilities (e.g., sequencing, planning, memory, etc.). The competent use of an AAC
system will always involve some degree of operational ability such as turning a device on/
off, volume control, etc. There is a risk that judgements of operational ability can dominate
the perception of competence, particularly during the assessment process. Competence
in AAC system operation does not, in itself, ensure functional use (Kraat, 1984).

Social Competence

This has its roots in pragmatic and speech act theory (Austin, 1962). It describes the ways
in which people use language in their interactions with others. Hymes (1972) neatly sum-
marises the social rules of communication as competence as to when to speak, when not,
and as to what to talk about, with whom, when, where, in what manner (p. 277). This
includes behaviours such as topic initiation, asking questions, accepting or refusing
invites, etc. Social competence can have a significant impact on how people who use AAC
are viewed (Light et al., 2003a,b).