Patients with complete paralysis, or locked-in syndrome, spend life mute. Often these conscious individuals are unable to relay even their most basic wishes because they have lost all muscle control. Now years of research on animals and humans is leading to the development of imaginative communication strategies for these patients. Several techniques that bypass the muscles and gain power directly from the brain are under investigation.

We might scream, point, nod, whisper, shrug, jabber, smile, dictate or email in order to relay information to the world. But people with complete paralysis, or locked-in syndrome, don't have these options. In fact, they often don't have any reliable communication options. Their normally functioning brains may wish to express a sentiment, but their muscles are deaf to the orders. They can't control their limbs to gesture or type and they can't control their mouths to speak.
      Now years of basic science and technological research may pay off for these isolated patients. Scientists are investigating several creative computer-based communication strategies that appear to bypass the muscles and receive commands directly from the brain.

The advances are leading to:

• imaginative communication methods.
• Insights into how technology can aid medical progress.

      Locked-in syndrome can result from a stroke or injury. Neurological ailments, such as Lou Gehrig's disease, also are culprits.
      The damage from the condition or injury blocks the message transmission path that initiates voluntary movement. Normally, a series of electrical impulses pass from brain cells along nerves to trigger the release of chemical messages, which eventually signal the muscles to move. Most or all of the muscles in locked-in patients never receive the messages. Some patients have a few spared muscles in areas such as the eyes. Computer programs occasionally aid their communication by detecting the remnant muscle movement, but often the muscles are difficult to control or easily tire.
      For decades it seemed beyond science's reach to help these patients. But then researchers began to investigate a long shot idea. Maybe they could bypass the muscles and power computer communication devices directly from the brain. Following years of research, the strategy, reminiscent of a science fiction movie, is now starting to show promise in real life.
      One variation involves an electrode that is implanted in the brain and picks up electrical impulse activity directly from a small number of brain cells, as found in studies of rats, monkeys and humans (see illustration). The activity or "thought" is transmitted to a translating software system designed to control a computer cursor and produce speech. An implanted patient, paralyzed from a stroke, recently appeared to show some success following hours of training. The patient can manipulate the cursor to slowly spell his name as well as activate icons that represent phrases of speech such as "See you later. Good talking with you."
      Other researchers are developing an electrode system that they hope will pick up electrical impulses from large numbers of brain cells. Plans are underway to test the system in monkeys.
      Several research groups also are studying nonsurgical techniques that indirectly pick up brain activity from outside the brain. This strategy relies on electrodes placed on the scalp that detect specific variations in the chatter of electric impulses elicited by large numbers of brain cells. One group trained four patients with locked-in syndrome from Lou Gehrig's disease to compose messages with a computerized spelling device. Following hundreds of training sessions, the patients learned to produce a certain electric impulse variation. A translating system then allowed them to slowly select letters on a computer screen by initiating the signal. Currently, the generation of a character takes about 30 seconds. One patient completed a letter in four hours.
      Researchers hope that adjustments in training and technology will improve and speed up these thought-capturing techniques, providing a useful communication option for locked-in patients.
      And you thought email was high-tech.

A group of researchers are trying to help patients with complete paralysis, or locked-in syndrome, communicate by directly connecting a computer to the motor cortex of the brain, which is vital for movement. Ideally, the patient's functioning brain cells grow into the glass cone of an implanted electrode that contains special growth-promoting molecules. Then the electrode detects, amplifies and transmits to a computer the activity of the brain cells that grow into the cone. The computer translates the signals into cursor movements that produce speech.

Illustration by Lydia Kibiuk, Copyright © 1999 Lydia Kibiuk.