Thanks to Sara for pointing this out. I already had 1UP bookmarked, but I have too many sites bookmarked to keep up with.
In response to this 1UP article: http://www.1up.com/do/feature?pager.offset=0&cId=3156848.
Some problems seem like they could be better overcome through hardware.
A mouse with a 4-point vibration system (forward, back, left, right) could indicate to a deaf person the direction of a sound relative to the player's character. Really, there's probably a lot of people with intact hearing as well who could appreciate such a device. A lot of people have poor sound systems. Others play at very low volume in the wee hours of the night, when family is sleeping. And still others have frequency-specific deafness, which can fool a person into believing he or she is hearing everything.
For the blind, a braille image translator (they're probably already available). I don't mean that it would translate absolutely everything in detail while the gamer is playing. One possibility is that it could translate figures' borders from the image during gameplay, so the blind person could feel with one hand while controlling his or her character with the mouse. This would not only give the person a general picture of the scene, but it would also simulate depth perception. Another possibility is for the blind person to access a compilation of detailed figure models, before starting gameplay, to learn at leisure. This system would work better with a braille machine employing multiple degrees of dot elevation.
I think an increasing amount of attention is being paid to game audio these days, which is great. But my impression is that it is still rare for foley designers to be present from the beginning of the concept-implementation phase. This is unfortunate for many reasons (for one, it disallows audio from helping shape video; trust me, it can), but it particularly affects the blind. An increased amount of well-crafted sound effects could go a long way in aiding the blind to imagine the scene and events.
I tend to watch DVDs these days with subtitles (a friend got me hooked). Often, the problem with subtitles is not that they are absent. The problem is that they are imprecise, unclear in meaning, set against a colored backwash which makes the words difficult to read, or (particularly in games) are too small. The last is particularly annoying, since one would think it is so easy to program a game to communicate with its console/PC, determine the resolution, and adjust the text size accordinly; or simply give the player the option of adjusting text size. A lack of semantic clarity and imprecision are likely the result of rushed inclusion of the feature or use of non-writers in translating audio to print. It's terribly unfortunate when important nuances, like voice (dialect), are lost in translation.
MUSIC FOR THE DEAF
The deaf may not be able to appreciate music like people with hearing, but I am certain they can appreciate it in alternate ways. The three core components of music pitch, rhythym, and volume.
Rhythym can easily be communicated through touch. Alone by itself, it can be enough to give one a thrill. Preferrably, whatever hardware communicated rhythym would be apart from the keyboard, mouse, or joystick; but it may have to be located on relatively sensitive skin in order to express rhythyms of fast tempos and staccato. A pair of such objects might even be used overlapping rhythymic parts (melody and accompaniement).
Pitch can be communicated visually. I've been a musician all of my life, and a songwriter/composer for most of it. Music has a visual element for me. If I'm listening to music, I'll often "conduct" with my hand using visual representations of melody. That is... my hand rises with ascending notes and falls with descending notes, by degree. Smooth hand motions represent audial slurs. Jabs/punches represent accented notes. A graphic representation could be produced that follows the same logic, and perhaps even uses separate bars (or whatever) of different colors to represent overlapping notes or instruments. This representation could easily be designed to be noticeable but unobtrusive, such as on a framed border of the screen.
I am not positive that deaf people have a sense of pitch, but they might. They do feel vibrations, and perhaps the deaf are able to notice a "tonal" difference between vibrations of equal strength, depending on what object causes it. But, if the deaf don't have a sense of pitch, a visual representation would, I'm certain, still be appealing to them.
And, of course, volume can be communicated both tactilely and visually. Disney's Fantasia does a wonderful job of visually expressing volume. The brightening and bleeding of colors beyond their frame is one method.
I have a blind friend at my university. I'll try to remember to ask him sometime what his thoughts on this subject are.
I would certainly like to see games made more accessible to other disabilities. I had a relative with MS who was extremely limited in mobility during his last several years. I think he would have loved video games, had they been around.
I spoke at length with my blind friend this morning, who has heard of video games for the blind and is interested in trying them. He has only been blind for about five years, so he could not speak for those who were born blind. However, he did graciously offer to speak with a local community of the blind about the subject of video game accessibility, so I might have more input in the coming weeks.
I asked my friend if he could recall any special difficulties with audio, but he couldn't think of any that don't bother sighted people as well.
He did like the hardware suggestions listed above, but there is one issue that would need to be resolved. In regard to text, he much prefers communication by braille text over computer vocalizations; for clarity, precision, and other reasons. That raises the question of how best to enable him to read chat dialogue, view the screen image (through the braille image translator), and control his character all at the same time.