With the advent of graphically oriented operating systems, it is vital to have access to a mouse or an alternative pointing device. For those who lack the coordination to use a standard mouse, there are many alternatives to consider. Trackballs are a good first choice; the control surface can be easier to manipulate, and the buttons can be activated without affecting the pointer position. Some trackballs offer additional buttons that add functionality, such as double clicking, click and hold, and other commands and can be programmed to a person's specific needs. A simple accommodation for use of a pointer by someone who can't use his hands but can move his feet is to place a standard mouse or trackball on the floor.
Other alternative pointers can be found in many mainstream computer stores and supply catalogs. External touchpads, similar to those built into many notebook computers, are ideal pointers for some. A handheld pointing device with a small control surface area may be useful for someone with very limited hand mobility. For a person with a mobility impairment who already uses a joystick to drive a wheelchair, a joystick-style mouse substitute may be an excellent choice.
A person with good head control who cannot control a mouse or an alternative pointing device with any limb should consider using a head-controlled pointing system. These systems use a transmitter or reflector that is worn on the user's head and translate head movement into mouse pointer movement on the computer screen. An additional switch replaces the mouse button. Combining a head-pointing system with an on-screen keyboard allows someone who cannot use a standard keyboard and mouse full computer control.
For more information about adaptive technology, consult Working Together: Computers and People with Mobility Impairments or view the video by the same title; also consult Working Together: People with Disabilities and Computer Technology or view the video by the same title.