Kenneth Colby, 81, a pioneer in the field of artificial intelligence and a UCLA professor emeritus of psychiatry and biobehavioral sciences, died April 20 of respiratory failure in Malibu. In the early 1970s, Colby created PARRY, a simulation of a paranoid mental hospital patient, at the Stanford University Computer Science Department's Artificial Intelligence Lab. Colby taught at UCLA from 1974 to 1990 in the fields of psychiatry and computer science and worked toward merging the two fields to develop at-home computerized therapy and a mobile voice synthesizer to aid stroke victims. In 1989, Colby and his son, Peter, founded Malibu Artifactual Intelligence Works, a company that developed Overcoming Depression, a cognitive therapy program featuring a natural language dialogue capacity.

Billy Higgins, 64, a legendary jazz drummer and member of the faculty of the UCLA Jazz Studies Program, died May 3 in Inglewood. He joined the faculty as a lecturer in January 1997 and taught percussion jazz ensemble as well as conducted private drum lessons. Higgins performed on more than 700 recordings; among the greats with whom he played were John Coltrane, Thelonius Monk, Sonny Rollins, Herbie Hancock, Pat Metheny, Milt Jackson and Joshua Redman. He won a Grammy Award in 1988 for best instrumental composition for "Call Sheet Blues" from the film "'Round Midnight," sharing the honor with co-composers Ron Carter, Herbie Hancock and Wayne Shorter. A tribute concert will be presented in Royce Hall at 8 p.m. May 26. For details, call (310) 825-5706.

John H. Lyman, 79, a professor emeritus of engineering and a pioneer in the making of artificial limbs, succumbed to cancer May 3 in Sherman Oaks. A psychologist by training, Lyman was "a man before his time," said Associate Dean John D. Mackenzie. Lyman joined UCLA's engineering systems department in the early 1950s to explore human-machine interaction. He also worked with the Veterans Administration and Northrop Aircraft Corp. to devise high-tech prosthetic devices, developing new concepts for artificial hand mechanisms to replace the commonly used wood and leather devices. A visionary, Lyman told Walter Cronkite in 1966 that he thought it would be possible by the 22nd century to whisk humans across vast distances by flashing their entire genetic code to a receiving computer in another part of the universe.

James W. Trent, 67, a pioneer in the field of higher education for his seminal research on college student development and a UCLA associate professor in the division of Higher Education and Organizational Change in the Graduate School of Education & Information Studies, died May 11 of a heart attack. Trent was recently named one of five recipients of the 2001 UCLA Distinguished Teaching Award and was scheduled to be honored at a UCLA Alumni Association Awards banquet on May 19. A member of the faculty for more than three decades, Trent created and served as director of the Education Studies minor and also developed UCLA's High School Advising Program, which trains UCLA students to serve as academic advisers in inner-city high schools.