Among the many concerns of people facing ALS, one question looms large: If I lose the ability to speak and write, how will I communicate?

Until a few years ago, options were severely limited. Families and therapists bought or improvised cards with printed messages or pictures and tried to frame questions so they could be answered with one of these or a yes-or-no signal. But ALS doesn't affect the mind, and people with this disease may have a strong need to express ideas more complex than "I'm tired" or "My nose itches."

The computer has changed life for people with disabilities of all kinds. If you're already using a computer and a standard word processing program, such as WordPerfect (WordPerfect) or Microsoft Word (Microsoft), you're ready to understand and evaluate special adaptations that can help you communicate. (Companies that make products mentioned in this article are listed in "Technology Transforms the Workplace.")

In case you're completely unfamiliar with computers, "software" means the programs, stored on computer disks, that tell the computer how to write, calculate and process information; "hardware" refers to the "guts" of the computer and its outer casings. Hardware may limit program use.

There are two major families of computers these days: those made by IBM and the many "IBM-compatible" computers like them, and those made by Apple Computer, mostly the Macintosh. Some software programs come in two versions, one for IBM-compatible systems and one for the Macintosh.

If you're not familiar with computers, you may want to buy one and master some basic skills before ALS progresses very far.

ADAPTING THE KEYBOARD

Word processing programs, used for writing and speaking via computer, are operated from a keyboard that looks a lot like a standard typewriter keyboard. But a computer does more. Special keys or key sequences (more than one key pressed at a time) allow you to edit, organize and store your documents.

Many computer keyboard operations require pressing two or even three keys at a time, something that becomes impossible if you can only use one finger. A simple adaptation, such as HandiSHIFT (Microsystems Software) or StickyKeys (IBM Special Needs Systems) lets you hold down two or three keys by pressing only one key.

If lack of hand coordination makes hitting the wrong keys likely, you can buy software that instructs the computer not to accept a key as "pressed" until it's been held down for a certain length of time.

Mechanical aids can also help people with limited use of their arms and hands. Plastic covers with holes for each key ("keyguards") increase accuracy for someone with an unsteady finger.

BYPASSING THE KEYBOARD

When hand weakness is far advanced, using a conventional keyboard becomes impossible. If voice control is still good, a "voice recognition" system may be an option at this time. But some of these systems recognize only certain words, and most require speech to be consistent. Since speech changes as ALS progresses and eventually may be entirely lost, voice recognition may not be a good investment in this situation.

For people with ALS, an "on-screen" keyboard may be a better choice. On-screen keyboard software programs give you a picture of a keyboard on the computer screen ("monitor").

Examples of on-screen keyboard programs are ScreenDoors (Madenta Communcations) for Macintosh systems and HandiKEY (Microsystems) for IBM-compatible computers.

SWITCHES

A "switch" is computer lingo for any method of using an on-screen keyboard or set of options ("menu").

A popular switch, used by people with and without disabilities, is called a "mouse." It's about the size of a small rodent and has a rotating ball on its "belly." You use a mouse by sliding the ball around a pad and pressing its "back" to select menu options or keys from an on-screen keyboard.

There are many other types of switches, designed to be operated by facial muscles, a puff of air or even your eye's fixation on one part of the screen.

A popular switch for people who can't use their hands is a head and mouth-controlled device, such as HeadMaster (Prentke Romich). You move around the keyboard by moving your head instead of your fingers and choose letter keys and other command keys by puffing into a mouth-held tube.

An ingenious but expensive (about $18,000) switch is built into the Eyegaze system (LC Technologies). This system uses a video camera to track and time eye movements. The computer lets you type and perform other functions even if eye muscles are all you can control.

SPEEDING UP TYPING

Creating written or spoken text by "pressing" one letter at a time with any kind of switch is slow. To help people write faster, there are tools called "word prediction" programs. They let you type a letter or part of a word and then show you a list of options to select with one keystroke. Examples are HandiWORD (Microsystems) for use with IBM systems, and Telepathic (Madenta) for Macintosh users.

MORSE CODE

There are also programs that combine a very old idea with very new technology. Tom King at the University of Wisconsin at Eau Claire says the fastest way for people using adaptive switches to communicate is with Morse code. Any kind of switch (mouse, HeadMaster and so forth) can be used with Morse code software to produce dot and dash signals that the computer converts to letters, punctuation marks and editing commands.

HandiCODE is Microsystems' Morse code software. The company says users can reach speeds of more than 40 words per minute compared to on-screen keyboard scanning rates of 15 to 17 words per minute even with word prediction.

SPEAKING VIA COMPUTER

But how does all this help you speak if you've lost your voice? Here again, technology comes to the rescue. Speech synthesizing software and hardware can mesh with your computer system, speaking what you write.

For IBM-compatible computers, you need a software program that reads what you've typed ("screen reader" program) and hardware that actually does the speaking. For example, Microsystems' HandiCHAT software program works with hardware like Digital Equipment's DECtalk or Echo Speech Corporation's Echo.

Apple's Macintosh computers don't need additional hardware to synthesize speech. Talk:About and Write:OutLoud (Don Johnston) are speech synthesis programs designed for Macintosh computers, including the portable PowerBook.

DynaVox software (Sentient Systems)comes in versions for Macintosh and IBM-compatible computers.

Several companies make compact, portable speech-synthesizing devices. Sentient Systems' DynaVox Communication Device (different from its software for Apple and IBM-compatible computers), Prentke Romich's Liberator and Crestwood's Crespeaker are examples.

Some systems can be used with adaptive switches, but others, especially the smaller portables, may require more finger control than many people with ALS can manage.