Introducing accessibility and assistive technology
Introducing accessibility and assistive technology
Computers and assistive technology
In this activity on accessibility and assistive technology we consider the technological adaptations used by people with different disabilities. In order to understand the adjustments that are needed to make online learning accessible, it is important for you to know what tools disabled students are likely to be using.
In subsequent sections we will look in detail at adjustments that may need to be made but in the meantime, although this is a long activity, we would like you to do as many of the interactive options as you can, as they illustrate the time effort required by successful disabled students. You will then need to expand your list of challenging activities to include possible solutions.
It is a fact of life that even in the most carefully designed course, not all students engage with the material in the same way. This may be because of differences in learning styles or it may be because of a disability or dyslexia. Different aspects of a course will be challenging for different groups of people. Some students may find it impossible to attend a face-to-face activity while for others reading and writing may be very difficult.
Many disabled people use a personal computer with a wide range of adaptations, which are called assistive or enabling devices or technology. Even very severely disabled people can use computers to read and write without help. This gives students greater independence and also a degree of privacy that is not possible if they are relying totally on human helpers. When the assistive technology is combined with online communication, some barriers caused by other people's reactions to disability are also removed.
The benefits of the technology can be negated by poorly designed interfaces provided for the various components of an online course. This will be discussed in more detail in Sections 4 and 5.
Sophisticated assistive technology can be expensive and students who need it may have to go through a long process of applying for financial awards, getting equipment in place and learning how to use it, all before they begin a course. The technology can also be complicated and, as with any group of users, not all students will learn to use all the advanced features.
A few mobile devices have accessibility features and there are some specialist computers designed with a disabled-only accessible interface; for example a portable computer with Braille-only input and output. We will concentrate on the most widely used products: that is software and hardware added to a PC, most often using a Windows platform.
We have arranged the information in the following sections by considering the main groups of disability and the technology that they use, although some students may use more than one assistive device and the same assistive device may be used by students with different disabilities.
It is important to note here that the descriptions in the following sections are rather general and this hides the wide diversity of impairments, abilities and experiences of disabled people. Grouping the categories as we do here, in order to understand the effects on studying, doesn't imply that people with each type of disability can be neatly divided into groups of ability.
You should keep the following points in mind while studying the following descriptions.
A disabled person will have many abilities that are unaffected by the impairment.
Disabled people are as diverse as the population they are part of in terms of their preferences, attitudes, etc.
Impairments vary in their severity, between people and over time.
It is fairly common for a person to have more than one disability.
People's needs and abilities change in relation to specific tasks.
Students studying at this course may have a disability.
There are approximately two million people in the UK who have a sight problem. The Royal National Institute of the Blind (RNIB) defines someone as having a sight problem if they are unable to recognise someone across the road or they have difficulty reading newsprint even when wearing glasses (RNIB, 2005, ‘About sight loss – changing the way we think about blindness’).
When discussing visually impaired people it is important to distinguish between partially sighted people (also known as people with low vision) and people with no useful vision (blind people). This distinction is important because these two groups interact with information and devices in very different ways.
Visual impairments can be caused by many different conditions. Some conditions are associated with aging, while others are congenital (present at birth). Different visual impairments have different effects on the person's vision: some impairments cause increased sensitivity to light; others result in a restricted or partially occluded field of view, such as lack of central vision or tunnel vision. Other conditions cause rapid and uncontrollable eye movements, which make it difficult to see clearly.
People who are colour-blind cannot distinguish between certain ranges of colour. The most common form is red-green colour-blindness. People with red-green colourblindness do not see these colours in the same way as most people do, and cannot distinguish between them. Approximately 1 in 10 men and 1 in 200 women are affected by red-green colour-blindness. Colour-blindness is either inherited or is caused by an underlying eye condition, such as macular degeneration (BBC, 2005, ‘Men's health’ ).
Access to PC output for blind people
Blind people access computers using a combination of software and hardware that present the visual contents of the screen in another form, either in synthesised speech or in Braille. A piece of software known as a screen reader directs the information that is sent to the screen to either a speech synthesiser or a refreshable Braille display.
Screen readers and speech synthesisers
A screen reader monitors the information sent from the computer to the screen. It makes decisions about which part of the screen to read and in what order, then passes this information to either a speech synthesiser or a Braille display. All screen readers support speech synthesisers and most support Braille displays.
The first speech synthesisers were hardware, usually a small box that sat on the desktop and had its own speaker, or a card that fitted inside the computer and used external speakers or those of the computer. These speech synthesisers are still in use, but it is now more common to use a software synthesiser, which generates audio output that is played by the computer's own sound system.
Screen readers and speech synthesisers
A refreshable Braille display is a row of cells each containing pins that represent Braille dots. These pins are raised or lowered to form Braille letters. The screen reader program sends text a line at a time or as set by the user. The hardware is expensive, a 40 character display costs about £4000 ($7000, €6000); so this option is most often used by those in employment. Its main advantage over speech output is that refreshable Braille distinguishes between individual characters, so there is no confusion over homophones such as ‘tale’ and ‘tail’. See the Refreshable Braille Displays website for more details.
The main advantage of using a speech synthesiser with a screen reader rather than reading a Braille display is that synthesisers are cheaper and information is absorbed faster than by reading Braille. The speed of speech output can be varied and experienced users can listen at the same rate as a person reads print silently.
There are several difficulties associated with using a screen reader and speech synthesiser or Braille display to access a computer. The main one is that it is very difficult to obtain a quick overview of the information on the screen because it is presented in a ‘linear’ manner. In other words, the contents of the screen are read out word by word and there is no equivalent of the visual glance. This linear approach also means that it takes much longer to read a screen-full of text using synthesised speech. In addition, synthesised speech can be very tiring to listen to over a long period of time, more so than human speech.
As well as presenting the information on the screen, screen readers also provide additional functionality to allow the user to interact with the information. For example, screen readers have commands for pausing or repeating the speech, and echoing back keyboard input. Screen readers often have two modes: one for reviewing information, for example continuous reading, which can automatically scroll down when the bottom of a screen is reached; and another for interacting with the information, for example editing text or filling in web forms.
When a screen reader is used with a speech synthesiser the user can control the amount of information that is read; for example a paragraph, a line, a word or a character at a time. The user can also move the focus backwards and forwards in the text, control the rate and pitch of the speech, and may be able to choose between different voices.
A list of some of the screen readers currently available is provided on the Resources page at the end of this free course. Navigate there using the 'jump to' facility in the navigation bar at the top of the page.
If you are unfamiliar with screen readers do ‘Activity task 3: using a screen reader’.
PC input by blind people
To input to the computer blind people can touch-type using a standard keyboard but can't use a mouse because this requires hand-eye coordination. Although it is possible to emulate mouse actions using the keyboard, it can be difficult to locate its position on the screen reliably. It is possible to use most Microsoft applications under the Windows platform without using the mouse at all by using keyboard shortcuts. The Help files of Microsoft applications and Windows provide lists of available keyboard shortcuts. There is an activity about this in the section ‘Physical impairments’.