Advertising imagery sparks the photos of American Brain.

Robert Raczka's latest series of photographs, American Brain, at Pittsburgh Center for the Arts, unravels a quest for sublime ambivalence. Raczka has extracted his images from a blazing media-saturated American culture scattered with drug-store displays, urban billboards and plastic flowers.

The show, which takes up a healthy two galleries on the PCA's first floor, is stunning when taken in at a glance. The color prints announce splashes of primary red, yellow and green. They line up bright and shiny, like penny candy in a glass display case.

On closer inspection, things aren't so easy. "I grew up in a time when football stadiums weren't for sale," Raczka says. What drew him to this project was the omnipresence of advertising -- the placement of which was someone's aesthetic decision, and which became his subject matter. In this way the exhibition is both a homage to and an analysis of the left and right brains of America.

Themes pop up: nature (trimmed shrubs and balloon flowers), brand names (Newport cigarettes! Visa!), symbols of identity (redneck, sexy blonde, cowboy) and concepts, such as patriotism, religion and militarism. The shots were taken over a series of years near Raczka's homes in Meadville and Pittsburgh, as well as in New York City, the Jersey shore and Las Vegas.

These places aren't necessarily recognizable: Raczka shoots at unlikely angles that create a flattened, collage-like look. That style also helps highlight the irony of a newborn-baby doll hanging limp and cold on display in a bright shop window, or a bikini-clad blonde in an advertisement with NFL pocket schedules at her feet and a prime line of Newports above her head.

Raczka sees this work as collaboration with the media culture. "These still lives and settings were constructed, just not by me," he says. "I'm recording them." He's also framing them in interesting ways. These images are not cropped or altered from the negative, so all of Raczka's headwork is done in the field.

Raczka grew up in Southeastern Pennsylvania, but he didn't grow up looking at art. "The whole tradition of painting -- abstract expressionism and the like -- I just wasn't exposed to it," he says. The first artist whose work struck him as stunning and awesome was Duchamp. The beauty of the everyday made sense. Duchamp led directly to Warhol. And there is definitely a sly irony hovering about in these prints.

"It's not a time for subtlety," says Raczka. "We're saturated with representation. I think it would be good if people just noticed it more. My goal is to experience ambivalence."