Pianist Denny Zeitlin’s Alter Ego: Psychiatrist : The musician has combined the seemingly incongruous worlds of psychiatry and jazz improvisation.

Ever since he was a child, Denny Zeitlin has been fascinated by the seemingly incongruous worlds of improvisation and psychology. He’s turned his youthful zest into an unusual dual career: jazz musician and psychiatrist.

He practices the latter 30 hours a week, both in private consultation at his office in Kentfield in the San Francisco Bay Area, and as an associate professor of psychiatry on the teaching faculty at the Medical Center of UC San Francisco. He practices the former as often as he can, as he will tonight and Saturday with his trio at the Vine Street Bar & Grill in Hollywood.

Zeitlin, 52, grew up in the Chicago suburb of Highland Park, Ill., in a family where his parents served as ideal role models for what was to become his two life works. “My dad is a doctor and he plays piano by ear and my mother, who’s a speech pathologist, was my first piano teacher,” he says. “When I was 2 or 3, I would crawl up onto the lap of whichever parent was playing and start picking out little melodies, so even though I extensively studied the classics, improvisation was always my first love in music.”

The pianist--who works here with bassist Tom Warrington and drummer Peter Donald and whose selections will in part be drawn from tunes off his two Windham, Hill Jazz albums, “Trio” and “In the Moment”--was led toward his involvement with psychology when he was just a youngster in grammar school. “I remember kids coming up and wanting to talk about themselves, and I was eager to listen to them and try to understand,” he says. “Early on I knew I would be involved in both fields, though I had no idea what direction it would take.”

The hirsute musician’s jazz life really began when he’d slip out at nights while in high school to play all-night sessions in Chicago with greats like Johnny Griffin and Ira Sullivan. “It was a great time in Chicago jazz history. I could be the only white cat in a club and it would be cool,” he recalls. Later, in 1963, while in medical school at Johns Hopkins University in Baltimore, Zeitlin was signed to a recording contract at Columbia by the renowned producer John Hammond that resulted in five albums, among them “Cathexis” and “Carnival.”

Citing influences from Bud Powell and Miles Davis to Arnold Schoenberg and Maurice Ravel, Zeitlin says his current presentation is a mix of originals and pop and jazz standards. “I love standards,” he says. “They’re such a bedrock to this music, and are a constant source of renewal. I love to reharmonize them, a process I hope retains their original character but also adds something new. And gives us something new as vehicles for improvisation.”

He’s very happy with his trio. Drummer Donald, a trapsman with zeal, has been a musical sidekick for eight years, while Warrington joined the crew a little over a year ago, replacing another fine bassist, Joel DiBartolo. “Peter and Tom have a wonderful ‘time’ feeling together and that opens up so many musical possibilities,” Zeitlin says.

Asked if there’s something distinctive about his music, Zeitlin says, “Wow, that’s a rough question. I like to think that I have taken my myriad influences from over the years and have integrated all of them into my own approach, my own style. I like to think it’s evolved in its own way. I still feel excited about the music and feel terribly grateful for the opportunity to play. It’s not something I ever take for granted.”

Club Crawl: In yet another changing facet of our Southland jazz environs, bands with name musicians are back at the Biltmore Hotel’s Grand Avenue Bar in downtown Los Angeles, at least for the time being. The subtle yet expressive drummer Ralph Penland fronts a trio Monday and Tuesday and former Poncho Sanchez pianist Charles Otwell leads a duo Wednesday-next Friday. Also on the sked: pianists Freddie Ravel (Jan. 14-15), Marty Harris (Jan. 21-22) and Brian O’ Rourke (Jan. 28-29) and dulcet-voiced songstress Cathy Segal-Garcia, backed by keyboardist John Hammond’s duo (Jan. 23-25). “We’re trying to get the best players we can get,” says Holly Barnhill, the Biltmore’s director of publicity, of the shift from a short-lived “soft jazz” format that drew scant crowds to the room. “We have to see who’s available, but musicians say they want to work with us.” Information: (213) 624-1011. . . . Saxophonist Carol Chaikin, an L.A. native who currently lives in Manhattan and whose debut Gold Castle release, “Carol Chaikin,” is doing quite well on the airwaves, plays a hometown date Sunday at At My Place in Santa Monica. It’s Gold Castle’s first entry into jazz (the label sports mostly singer-songwriters), we’re really excited with the results,” says Jeff Heiman, GC vice president of promotion. Information: (213) 451-8596.

Rim Shot: Elvin Jones, who brings his band into Birdland West in Long Beach next Friday and Saturday, gives a free clinic and playing demonstration on Wednesday, 1 p.m., at the Musicians Union Auditorium ( 817 Vine St., Hollywood). Rudy Regalado’s salsa band, Chevere, opens the event. Information: (213) 469-6285.