BOSTON (AP) - For years, futurists have dreamed of machines that can read minds, then act on instructions as they are thought. Now, human trials are set to begin on a brain-computer interface involving implants. Cyberkinetics Inc. of Foxboro, Mass., has received Food and Drug Administration approval to begin a clinical trial in which four-square-millimeter chips will be placed beneath the skulls of paralyzed patients. If successful, the chips could allow patients to command a computer to act - merely by thinking about the instructions they wish to send. It's a small, early step in a mission to improve the...