More about Thinking about Thinking for AAC (TAT4AAC)


All humans are learners. Individuals have unique learning profiles. Learning to communicate is a basic human right. Learning to use AAC technology is complex. This online resource provides information by summarizing literature in the fields of AAC and cognition to support clinical decision-making.


Thinking about Thinking for AAC (TAT4AAC) is an interactive online resource summarizing literature from the fields of augmentative and alternative communication (AAC) and cognition.

It was developed to:

  1. Provide references about the cognitive demands of specific features of AAC technologies.
  2. Provide opportunities for clinicians to consider and compare the cognitive demands of AAC technologies.

There are two parts: an online interactive library and a resulting annotated bibliography. Upon completion of the interactive library, a printable PDF is generated that lists pertinent references and summaries related to the selected AAC features and their cognitive demands.

What Thinking about Thinking for AAC (TAT4AAC) is:

  • NOT an assessment tool.
  • NOT a prerequisite list of cognitive skills needed before AAC technology is introduced.
  • NOT a list to determine eligibility for potential device trial, purchase or training.
  • NOT a list of cognitive skills needed before device trialing or purchase.
  • NOT a base to eliminate AAC options for individuals who may rely on AAC technologies.


The Thinking about Thinking for AAC (TAT4AAC) was generated by the REKNEW team at OHSU, part of the Rehabilitation Engineering Research Center on Augmentative and Alternative Communication (RERC on AAC). A literature search was conducted to identify information related to AAC features and their cognitive demands. Through consensus, relevance was determined for inclusion in the interactive TAT4AAC library. Each relevant source was summarized and incorporated into the library.

Content Development Process:

  • Reviewed feature matching lists to identify specific AAC features which impose a cognitive demand on the user.
  • Completed comprehensive literature review of cognitive theory to identify those domains related to AAC, specifically: attention, memory and executive function.
  • Validated identified AAC features and cognitive domains with nationally recognized subject matter experts in fields of AAC and cognition.
  • Completed a comprehensive literature review of online databases, texts and relevant journals through combining key terms: specific AAC feature + a cognitive domain. This literature review was completed on July 1, 2019 and therefore library only contains resources up to that date.
  • Identified relevant findings through consensus process, including interrater agreement.
  • Generated literature summaries to make information easily accessible to clinicians.

What is AAC?

AAC (augmentative and alternative communication) refers to a communication process which relies on a collection of tools and strategies to help people share messages. As the term suggests, AAC may either augment natural speech or serve as an alternative to speech.

We all use AAC tools and strategies to share information, whether we are waving hello, texting a friend, or writing an email. Individuals with complex communication needs have a critical reliance on AAC in order to participate to their greatest potential in all aspects of their lives.

Individuals who rely on AAC have many ways to share information, forming an AAC system that can adapt according to the tools available, the context, the nature of the message, and the communication partners involved. Effective communication occurs when a message is generated and understood by another person, regardless of the means.


AAC tools and strategies are often divided into two categories:

Unaided approaches do not require tools or equipment, and include speech, gestures, facial expressions, and sign language.

Aided approaches involve two types of tools:

  • Those that do not require a battery or power supply, such as pen and paper or printed communication boards or books.
  • Those that require power supply, such as a tablet with a communication app or a dedicated speech-generating device.


AAC devices can be described according to four primary features:

Access is the means by which the user makes a selection on the device or software. Access may be either direct or indirect.

  1. Direct: A person using direct access selects a desired item on a display, either by using a body part (e.g. finger or toe), an instrument (e.g. stylus) or adaptive technology for cursor control (e.g. head tracking, eye tracking, or adapted joystick).
  2. Indirect: A person using indirect access is typically an individual who cannot control the muscles necessary for direct access, and uses one or more switches to make selections with a scanning interface.

Language refers to the vocabulary available on the tool, device, or software, and may include text, images, or a combination of both. The representation of language in AAC technology is dependent on a person’s literacy skills and communication needs, and organized according to preferences, efficiency, or learning optimization.

Display refers to how language is presented on the tool, device or software, and may include grids, visual scenes, keyboards, or a combination. Displays may be static (i.e. the screen remains constant regardless of user input) or dynamic (i.e. screens change according to selections made by the user).

Output is the means by which the device or software produces a message that can be heard or read by the user and communication partners. Output may include synthesized (computer-generated) or digitized (recorded) speech, text, or other visual representations of language, such as symbols.

What is cognition as it relates to AAC?

Cognition refers to the human mental processes of acquiring, using and understanding knowledge. Although there are many domains within cognition that are used to describe these thought processes, the Thinking about Thinking for AAC (TAT4AAC) examines three cognitive domains employed while using AAC: attention, memory and executive function.

Attention: sustain focus on a task while maintaining and shifting focus as necessary between various visual, auditory or tactile stimuli.

Examples of attention demands for a person who relies on AAC:

  • Focus on cursor as it moves from box to box on a grid for auto scanning.
  • Attend to the accuracy of a selection while typing an intended message on the keyboard.

Memory: maintain task-relevant information in mind while performing an activity until completion.

Examples of memory demands for a person who relies on AAC:

  • Retain the intended phrase-length message while generating the message word by word.
  • Remember the content and location of stored messages within a dynamic, multilevel display.

Executive function: a set of complex, higher order processes involved in the planning, organization, regulation, and monitoring of goal-directed behavior.

Examples of executive function demands for a person who relies on AAC:

  • Initiate navigation through multiple pages.
  • Choose the most efficient navigation path.
  • Monitor performance & correct errors.
  • Locate and select the target symbol within a dynamic, multi-level display.