The experiment looks like some ingenious test of mental telepathy. Seated inside a small isolation booth with wires trailing from the helmet on her head, the subject seems deep in concentration.
She does not speak or move. Near by, a white-coated scientist intently watches a TV screen. Suddenly, a little white dot hovering in the center of the screen comes to life. It sweeps to the top of the screen, then it reverses itself and comes back down. After a pause, it veers to the right, stops, moves to the left, momentarily speeds up and finally halts —almost as if it were under the control of some external intelligence.
In fact, it is. The unusual experiment, conducted at the Stanford Research Institute in Menlo Park, Calif., is a graphic display of one of the newest and most dazzling breakthroughs in cybernetics.* It shows that a computer can, in a very real sense, read human minds. Although the dot's gyrations were directed by a computer, the machine was only carrying out the orders of the test subject. She, in turn, did nothing more than think about what the dot's movements should be.
Brainchild of S.R.I. Researcher Lawrence Pinneo, a 46-year-old neurophysiologist and electronics engineer, the computer mind-reading technique is far more than a laboratory stunt. Though computers can solve extraordinarily complex problems with incredible speed, the information they digest is fed to them by such slow, cumbersome tools as typewriter keyboards or punched tapes. It is for this reason that scientists have long been tantalized by the possibility of opening up a more direct link between human and electronic brains.
Brain Waves. Although Pinneo and others have experimented with computer systems that respond to voice commands, he decided that there might be a more direct method than speech. The key to his scheme: the electroencephalograph, a device used by medical researchers to pick up electrical currents from various parts of the brain. If he could learn to identify brain waves generated by specific thoughts or commands, Pinneo figured, he might be able to teach the same skill to a computer. The machine might even be able to react to those commands by, say, moving a dot across a TV screen.
Pinneo could readily pick out specific commands. But, like fingerprints, the patterns varied sufficiently from one human test subject to another to fool the computer. Pinneo found a way to deal with this problem by storing a large variety of patterns in the computer's memory. When the computer had to deal with a fresh pattern, it could search its memory for the brain waves most like it. So far the S.R.I, computer has been taught to recognize seven different commands—up, down, left, right, slow, fast and stop. Working with a total of 25 different people, it makes the right move 60% of the time.