AAC Chapter Four Flashcards
Selection Set
Includes the…
Most AAC techniques utilize..
visual, auditory, or tactile presentation of all messages, symbols, and codes that are available at one time to a person who relies on AAC
visual displays of items in the selection set
Types of Selection Sets
Fixed (or static) displays – usually low tech
Dynamic displays – when activated, change screen to show new set of symbols
Hybrid displays – electronic fixed with dynamic component
Visual Scene Display – picture, photo, virtual environment depicting a situation, place, experience
Can you use a VSD on a 7-level communicator?
How have companies compensated for the limited number of symbols or images available on a lower-tech device?
Word prediction would fall into which category?
Yes
They have created levels within the device
Combined?
Process
You’ve already…
Chosen messages
Chosen symbolization or encoding strategies
Now consider…
physical characteristics of selection set displays
Physical Characteristics of Selection Set Displays
Number of items
Size
Spacing and arrangement
Orientation of the display
Which of these does your book say is most important?
Number of items
Most important factor is the …
number of messages, symbols, codes, and commands that the individual requires
Size for visual displays
2 issues
- individual item size
2. Overall display size
Individual item size – (for visual) determined by
***visual capabilities,
***motor access technique employed,
type of symbol,
number of items to be displayed
Overall display size – determined by
number of items that must be displayed
size of individual items
spacing of items
mounting and portability factors
physical capabilities of the person using the AAC
Size for Auditory and Tactile Displays
Auditory displays: determined by
Tactile displays: depends on
individual’s memory and ability to retain the organizational scheme of the display
tactile recognition abilities
Spacing and Arrangement of Items
Determined by
**Visual capabilities
**Motor control capabilities
Orientation:
Position of the display relative to _____
Determined by:
If scanning, determined by:
the floor
Postural capabilities
Visual capabilities
Motor capabilities
Visual factors
Postural factors
Selection Techniques
Direct Selection***
Scanning
Direct Selection Options
Physical contact - touch
Physical pressure or depression – keyboards, headstick, pencil/stylus
Pointing (no contact) – eye pointing, tracking, gazing, laser pointer, infrared
Speech recognition – for those with mild/moderate distortion
Some AAC systems support access options and others don’t.
What about keyguards?
?
Direct Selection Activations Strategies
Timed activation – dwell time
Release activation – maintain direct contact
Filtered or averaged activation
Scanning Patterns
Circular scanning – least complicated
Linear scanning – passes over every option
Group-item scanning – ex. Row-column scanning (can make own groups)
1 reason for choosing scanning over direct selection?
being unable to physically do direct selection
physical abilities/ disabilities
Consider…
scanning timing and speed
Selection Control techniques
- Directed (inverse) scanning
- Automatic (regular or interrupted scanning)
- Step scanning
- Directed (inverse) scanning
- Automatic (regular or interrupted scanning)
- Step scanning
activate switch until desired selection then quit activation
activate switch to start scanning then activate switch to stop scanning
only moves through selections if switch is activated, then either pause or use another switch to choose selection
Feedback
Provided during message construction
Purposes:
- Activation feedback:
Let the individual using AAC know that an item has been selected – click, ding, beep… - Message feedback:
Provide the individual with information about the message that has been formulated or selected
Feedback is available through:
auditory, visual, tactile, or proprioceptive modalities
