Two Switches for Success:
Access for Children with
Severe Physical and/or
Linda J. Burkhart, Dale Gardner-Fox
M.S., RPT, Gretchen Hanser MS, OTR/L,
Deanna K. Wagner, MS/CCC-SLP
Which Students and Why?
Types of Scanning & the Demands
A Closer Look at the Cognitive & Motor Demands
- Sensorimotor demands
- Language components
- Considerations for Parallel Programming
Keeping the Balance
- Motor load
- Cognitive load
A Closer Look at Motor Learning
- Development and use of cognitive/motor schemas
- Motor loop
Stepping Stones to Switch Access
Step 1: Single Switch - Cause and Effect
- Momentary/direct activation to get started
- Short timed segments for more active engagement
- Toys with a mission
- Simple Means-Ends
Step 2: Single Switch - Multiple Locations and Multiple Functions
Note: Strive to achieve a balance between leaving a switch
in one place long enough for the child to accommodate to it, and experimenting
with moving the switch to a place that might be easier for the child to
- Locating a switch in multiple locations
- Developing some motor automaticity, through repetition
with moderate differences - without the stress of timing
- Using a switch with clear intent
- General social and pragmatic timing
- Sequenced social scripts
Step 3: Two Switches - Two Functions
- Increase motivation by increasing cognitive engagement
- Two switches trial and error
- Two switches positionally related to function (Left
Right Switch Activities on this CD)
- Two switches social turn talking
- Two switches / two functions - Appropriate pragmatic
use of function
Types of Scanning - to increase choices and control
- Automatic Scanning
- Inverse Scanning
- Step Scanning with a Delay
- 2 Switch Step Scanning
- Morse Code
Why Two Switch Step Scanning?
- Eliminate need for Timing
- Concentration / Distraction
- Allows for more appropriate social skills and pragmatics
- Active vs. Passive Control
- Separate Function for Each Switch: Simple Cognitive
- One switch advances scan with each activation, the
second switch selects the item.
- Very few options are available for a single switch
user beyond cause and effect
Different Cognitive Levels:
- Some children have difficulty moving to two switch step scanning
because they do not yet understand the cognitive task. These students
will go on to Step 4.
- Some Children will understand the concept of 2 Switch Step Scanning,
as soon as they are shown how it works. These students will go on
to Step 5.
Step 4: Learning to Two Switch Step Scan
- One switch is the mover or lister and one
switch is the get it or selector switch
- Children who dont understand the concept of two switch step
scanning, may need this intermediate step to experience one switch
as the mover and one switch as the selector.
- These children may appear to activate the two switches randomly
and without discrimination of function.
- Use battery powered toys to move to a location for a play purpose.
Use a delay timer that moves the toy a short distance for each activation.
Step 4a: Side Step: Single Switch timing - Following
this step may lead to variations of steps 5-8 for automatic scanning,
inverse scanning or step scan with a delay
- Some children show an ease of activating the switch that indicates
they will be able to activate a switch in a timed mode. For these
children, you may want to probe this ability by presenting simple
single switch activities that require timing. Experiment with automatic
scanning, inverse scanning and single switch step scanning with a
- Other children may not be ready for a timed form of scanning until
step 8, at which time, they may have developed enough motor automaticity
with a switch to be successful with timed scanning.
- Some children may always be faster with two switch scanning and
never use a timed scanning.
Step 5: Two Switch Step Scan Errorless Learning - any
- This type of activity offers the child a variety of choices through
two switch step scanning, but any response is accepted as the child
plays or creates a story, rhyme or errorless letter.
- Similarly the child can use a series of communication displays to
direct the action of another person in a play activity script.
- The child can scribble with a talking word processor
with a limited set of letters.
- The child can use different computer voices to listen to a selected
tongue twister or silly saying.
- The chid can use a communication device to direct action in a game
such as follow the leader or draw a face, with options that all make
Step 6: Two Switch Step Scan for Clear Choices: Activities for
Increasing Accuracy and Cognitive Engagement:
- Insert some blanks in the array of choices with a communication
display or software activity.
- Use a word like click or nothing repeatedly
and have the child listen/look for a target word such as: read,
sing, or show me! Vary the number of clicks
- When the child selects one of these choices, the feedback shows
that it is somehow not logical or not reinforcing. Hopefully the child
will not select that item again, and pay more attention to selecting
a fun or appropriate choice.
- Use partner assisted scanning and model self-talk, hmm, no,
no, yes, thats what I want
- The number of blanks or clicks before a target item, should be varied
to prevent the child from just learning a motor pattern, instead of
staying cognitively engaged to make a clear choice.
- Gayle Porters light tech multi-page dynamic displays
- Step 7: Practice for Increasing Accuracy with Two Switch Step
- There are an endless variety of activities that can be set up to
give children experience with two switch step scanning using authoring
programs and communication devices.
- Try activities with some correct answers and some incorrect answers
- Add slightly negative or illogical items in the array of choices,
or simply no and repeat what to listen/look for.
- For communication displays, select vocabulary items that have different
pragmatic intents, so that the responses from the listeners provide
clear feedback for the childs comments.
- Once the child understands the process, then two switch scanning
can provide an access strategy to many curricular applications as
well as a means of communication. Music, animation, and logical or
humorous sequences are often a good starting place.
- Use errorless activities that allow the child to be creative and
generative: For example, errorless letters.
- Provide emerging literacy activities for creating stories, playing
with sounds and letters, or constructing a rhyme or sentence.
- Keep motivation high and customized for the child
- With successful and motivating practice, the child will be developing
more motor automaticity, and integration of cognitive and motor tasks
- Step 8: Two Switch Step Scan Reducing Time for Success
(for children who understand the process of two switch step scanning,
and have developed some motor automaticity for the task)
- Present a limited array at appropriate times to increase efficiency
(combining letters with word endings)
- If the child is just spelling out a controlled set of words, it
may be faster for the child to be presented with only the possible
letters instead of the whole alphabet array.
- If the child is creating sentences, selected words can be offered,
instead of the child having to spell out each word.
- Make use of sentence starters, endings and phrases.
- Use the feature of natural branching to present a limited number
of choices at each logical step of a discussion, sequence of activity,
composition or story. (For example: the next logical vocabulary needed
in a sequenced type activity, automatically appears, instead of having
to be navigated to from the main page.)
- Set up the array so that incorrect pictures or items disappear after
- Provide practice for rehearsing or studying for a test in a child-controlled
flash card format.
- Provide multiple choice instead of fill in the blank activities.
- Provide feedback in the form of a voice-output/written explanation
for illogical choices.
- Utilize electronic "Word Walls" and "Word Banks"
to provide access to frequently used words.
- Consider using word prediction or picture/word prediction.
- Consider using encoded alphabet displays for spelling.
- Explore other switch access strategies, such as Morse Code.
Linda J. Burkhart Linda@Lburkhart.com
Gretchen Hanser MS, OTR/L email@example.com
Dale Gardner-Fox M.S., RPT firstname.lastname@example.org
Deanna K. Wagner, MS/CCC-SLP Dwagner@swhd.org