HEAD (1968) *** Ah teyll yew whut: when they get that '60s psychedelic ultrafrenetic surrealist stuff going--,-it's neon aquatic. Just in case someone thought to call him a dumb hippie, Jack Nicholson includes a prescient splice of Reagan who is clearly out-dueled by Frank Zappa in a cameo with a cow. The Monkees are good, the cops are in the bathroom, and Rita Hayworth knows more than the yogi who waxes anti-Socratic when he says he knows nothing.