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Level 0.0
Passive, no input
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level 1.1 level 1.3
1 switch Touchscreen
single input single input
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level 2.1 level 2.2 level 2.3
1 switch 2 switch Touchscreen
build/animate build/animate build/animate
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level 3.1 level 3.2 level 3.3 level 3.4
1 switch 2 switch Touchscreen Joystick
timing/accuracy timing/accuracy timing/accuracy 4 directions
Joystick
2 directions
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level 4.1 level 4.2 level 4.3
1 switch 2 switch touchscreen choice
choice choice
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level 5.1 level 5.2 level 5.4
1 switch 2 switch scanning Joystick
scanning scanning
Level 0.0
This is purely passive. The student has no input to the computer.
The aim of this level aim is to stimulate the visual and auditory centres
in the brain. The variables that can be altered are size, colour,
shape, movement, location, timing, and sound.
A basic reason for using I.T. with our pupils is to allow them to
experience a degree of autonomous control . So these 'passive'
programs should be used and monitored carefully. They are
especially useful for assessing pupils hearing and vision
capabilities.
Level 1
These are single input programs, fundamentally a straight forward
cause and effect. A single switch press leads to a single
response.The screen then clears and awaits the next switch press.
Programs at this level are usually bright and noisy to gain the pupils
attention. The variables that can be altered are the time of display,
the colours used and the sound. Digitised pictures of pupils, family
and friends with sound samples taken from real life can be
especially motivating.
In using programs at this level the length of time the display
remains on the screen is important; too long and the pupils
attention is lost and he/she may not connect the response with the
switching operation; too short and the student may not have had
time to shift his/her attention to the screen.
Level 2
These are switch building programs. The program responds to each
switch press by drawing part of a picture. Repeated switch presses
are required to finish the picture. When the picture is completed a
short animation is usually the final reward. The screen then clears
and the program waits for the next switch press to continue. The
pupil is learning to become more discriminating and to concentrate
for a longer period of time. The variables that can be altered are the
number of switch operations to complete the picture (and thus the
time required for the pupil to concentrate), the colours used and the
sound.
The main difficulty with programs at this level is switch banging;
the student can operate the program by tapping the switch
repeatedly whilst paying no attention at all to the computer screen.
The computer switches can be positioned so that switch banging is
not encouraged (by increasing the difficulty of physical access to
the switch or placing where the pupil has to reach up to touch it) or
use two switches (level 2.2).
Perhaps the pupil needs to move on to something more demanding
or more interesting, certainly I have found switch banging less
frequent when using the better sounds and graphics on the newer
computers
It can also be important to let the pupil know when he/she has
pressed the switch with an auditory and visual cue.
With the two switch operation of this level (2.2) the switch
operation can be shared between two pupils enabling a degree of co-
operation and changing the nature of the interaction from a solitary
task to one promoting turn taking and communication. It can be
used as the basis of a small group activities and group games.
Level 3
These are switch accuracy programs. The pupil in operating these
programs is required to press his switch at a particular time in
response to an event on the computer. He/she has to monitor the
events on screen, judging when to press the switch and when not to
(the waiting is often the most difficult part).
The variables that can alter the degree of accuracy are the speed of
the target, the size of target and the sound.
The cognitive and operational differences between level 2 (switch
building) and level 3 (switch accuracy) are considerable.
On the switch building level the student is encouraged to
repeatedly press a switch, and can do so without reference to the
computer program. However level 3 demands that the student
continually monitors the program to achieve a successful switch
press at the right time. Pupils can often be confused when some
switch presses are successful and others are not.
In part the operation may rely on a certain cognitive ability some
pupils may never achieve. There are however teaching strategies
and linking activities to promote accurrate switching:
Using two switch building (Level 2.2) programs in which the
student has to touch more than one switch for each progressive
effect and using two physically different switches e.g. a press
switch and a wobble switch.
Using switches at different positions e.g. one on the floor and one
on the table.
Using related switch accuracy activities (switching on tape
recorders, radios and light room apparatus with a timed switch
operation)
Using switch accuracy programs with the teacher in control of one
of the switches, so the student has to tell the teacher when to
operate the switch.
Using physical guidance to help the student to operate the switch at
the necessary time and progressively reducing the help.
Level 4
These are switch choice programs. These include matching and
snap type activities. In these programs the student is selecting an
element from a number of alternatives which may be assigned to
different switches or that may be displayed in a row along at the top
or bottom of the screen. The variables include the number of
elements to choose and match and the differences between them.
Level 5
These are switch scanning programs. The student is presented by a
matrix of symbols from which he/she can choose an item. The
variables are speed of scan (for 1 switch operation), size of grid
(usually 2,4,8 or 16), and the elements within the matrix.
Scanning is an important skill necessary for the operation of switch
operated speech machines and of switch based word /symbol
processors. The different methods of scanning (one/two switch, the
different selection methods) and their relative merits are fully
examined in the Ace centre document "A Common Terminology for
Switch Controlled Software" 1990.
There does not appear to be a practical progression within
scanning; from a one switch to a two switch method, both have their
problems and inherent weakness. Fundamentally what is occurring
is the reduction of a multi-choice complex (the individual) to a one
or two state switching operation which is then expanded back to a
multi-choice condition at the computer end usually through some
kind of scanning access to a grid of words or pictures.
There are proportional switching methods that can either respond
variably to the pressure applied to the switch, or to the distance the
switch mechanism is pushed or to the time the switch is activated. I
think these switching methods could be usefully explored since the
present simple scanning methods are not very successful for pupils
who have severe learning difficulties.
All these levels are further subdivided according to the method of
input (.1 one switch, .2 two switch, .3 touchscreen, .4 joystick).
Thus level 2.1 is one switch building and level 5.2 is two switch
scanning.
All our switch based computer software is catalogued under this
scheme allowing us to assess and choose appropriate software for
each individual, to provide precise aims and objectives for computer
use and to chart any progression. It also allows us to sort all our
software into manageable and useful categories.
A simple method of recording computer use is also essential. Fig 2
shows our everyday recording sheet which is easily and quickly
filled in after every computer session. This allows us to build up a
picture of an individual's computer use throughout the school, to
note what was successful, and to avoid repetition. In addition it
allows us to monitor which level of software is being used most and
to plan which software we need to purchase.
With the more powerful computers now coming into education the
opportunities for using microtechnology with our pupils is
increasing. Simple authoring switch based programs whose graphics
and sound can be selected by the teacher perhaps with reference to
the pupils interests or friends can now be constructed. Newly
developed programs allow the teacher/therapist to choose the kind
of input (e.g. switches, touchscreen etc.) he/she wants. This enables
the operation to be tailored more precisely to the needs of the
individual. High quality speech can be produced by the computers
themselves without recourse to additional hardware. Hypertext (the
mixing written words, symbols, photographs, video and sound) is
now available on computers in schools. The possibilities for
personal profiling using the computer are very exciting;
constructing personal record of achievement documents and
recording evidence and achievements using video, scanned images
and recorded sounds.
Acorn software (Level 1)