Mouse and Keyboard Alternatives for Computer Accessibility

Mouse Alternatives
Students with physical disabilities are provided with certain mouse alternatives through Macintosh OS X and the Windows Operating System. These alternatives allow students to use movements that they are most comfortable with to direct a mouse pointer.

Trackballs act as a mouse that remains in one place. The mouse pointer moves in response to a stationary ball that is rotated on a base. Buttons are also positioned near the ball that have the same function as the buttons on a mouse. There are large trackballs, standard trackballs, and mini-trackballs. Mini-trackballs work well for students with good fine motor control but have a very limited range of motion

Joysticks are similar to trackballs, but instead of a ball, there is a movable handle that is perpendicular to the base.

Eye-gaze systems use a students' eyes to direct a mouse pointer. Infrared-sensitive video cameras determine where a student is looking and then move the mouse pointer to that spot. Clicking can be done by using a switch or blinking an eye. This type of mouse alternative is used by students who have limited muscle movements in their hands and/or head.

Keyboard Alternatives
Although standard keyboards work well for most students, students with disabilities have trouble using them. Expanded keyboards are over-sized keyboards that offer a larger surface. Students with poor fine motor control who need a large area to perform an accurate key stroke benefit greatly from this type of alternative keyboard.

On-screen keyboards display an image of the keyboard on the computer screen, and letters/functions are selected by clicking on them with a mouse/mouse alternative. They provide computer accessibility to students who are unable to use a keyboard because of motor skill deficiencies but can control a mouse/mouse alternative. Students who also have trouble refocusing their attention from the monitor to the keyboard and back to the monitor again benefit from this tool.

Resource: Dell, A., Newton, D., Petroff. (2012). Assistive technology in the classroom: Enhancing the school experiences of students with disabilities. Boston, MA: Pearson Education, Inc.

Computer Accessibility Features for Users with Disabilities

Apple and Microsoft are both devoted to providing computer accessibility to individuals with disabilities. Both of these companies offer a wide variety of features for users with physical disabilities, vision impairments/blindness, and hearing impairments/deafness. Computer accessibility features include:

Keyboard Modifications
Filter (Slow) Keys adjust how long a key can be pressed before it is recognized by the computer. By using slow keys, repeated key strokes or unintentional key strokes are minimized. This directly benefits students with hand tremors, muscle weakness, or fine/gross motor control deficiencies. Click here to watch a video on filter (slow) keys!

Mouse Control
MouseKeys allow users to control the movement of the mouse pointer through the numeric keypad. Students who can use a keyboard but have difficulty using a mouse benefit greatly from this device.

On-screen keyboards display a visual keyboard on the computer screen where users with limited motor control can use the mouse to click on desired keys for typing.



Modifications for Students with Sensory Impairments
Both Mac and Windows 7 provide individuals who are deaf or hard of hearing with visual signals that take the place of auditory prompts when their attention is needed. For example, a flashing caption bar might appear when a user needs to make a selection. In addition, enlarging images on a monitor can be applied on both Mac and Windows 7 for users with low vision. For individuals who are blind, a feature known as voiced feedback can be used. This tool reads items on the screen for its user. Items read aloud include menu bars, icons, dialogue boxes, and text.


Resource: Dell, A., Newton, D., Petroff. (2012). Assistive technology in the classroom: Enhancing the school experiences of students with disabilities. Boston, MA: Pearson Education, Inc.

Enhancing Communication for Students Who Are Hard of Hearing

Although students who are hard of hearing can understand speech through a combination of hearing aids and lip-reading techniques, they face many obstacles in a typical education classroom. If a teacher is lecturing quickly and using a quiet and unclear voice, students who are hard of hearing often have trouble following what is being discussed. Poor acoustics in the classroom, such as noisy heating/cooling systems decrease hearing aid effectiveness. When a teacher turns his/her back, these students will have a difficult time lip-reading or hearing what is being taught. Social interactions between teachers and peers are also diminished for students who are hard of hearing. Many times, the inability to communicate successfully causes feelings of isolation and frustration for these students.

Hearing assistive technology helps students communicate effectively in the classroom. Assistive listening devices (ALDs) can catch the sounds of a teacher's voice and amplify it. They also diminish background noise and poor room acoustics. Specific examples of ALDs include FM systems and soundfield amplification systems. With a FM system, the teacher wears a microphone and the student either wears headphones or has a connection set up to their hearing aids. When the teacher speaks, his/her voice is broadcasted to the FM receiver worn by the student and amplified through the headphones or hearing aid. The soundfield amplification system broadcasts the teacher's voice through loud speakers in the classroom. These loud speakers can be mounted on the wall or ceiling of the classroom.







Resource: Dell, A., Newton, D., Petroff. (2012). Assistive technology in the classroom: Enhancing the school experiences of students with disabilities. Boston, MA: Pearson Education, Inc.