Network television's decades-long domination of the public's attention faces a serious challenge from emerging video technologies, particularly cable TV, according to a specially assembled panel of national media leaders.

The "1985 Media Leaders Survey" further indicates that the quality of American life over the next five years is going to be substantially affected by these technological changes, but there is disagreement among the panelists over the direction of these changes.

Those are the underlying messages in the preliminary survey of 111 media leaders assembled by Robert Roy Metz, president and chief executive of United Media, a Scripps-Howard company.

Among panelists' predictions:

The quality of American life will: improve a great deal, 19 percent; improve somewhat, 40 percent; exert a mixed influence, 40 percent, and diminish, 1 percent.

The time people spend at home will: increase a great deal, 4 percent; increase somewhat, 65 percent; remain the same, 29 percent, and decrease, 2 percent.

Interactive electronic services (shopping, banking) are: very close, 11 percent; somewhat close, 46 percent; somewhat far off, 34 percent, and very far off, 9 percent.

Panelists also were asked to evaluate the change in people's daily use of five video technologies (network television, cable TV, videocassette recorders, personal computers, on-line data bases and videotex services) between now and 1990. They predict increased public usage in all areas save network television, although they agree it still will be the No. 1 medium in 1990.

"If I were in the broadcast media," says social scientist John Crothers Pollock, director of the survey, "I would be concerned."

Predicted growth for the other technologies over the next five years: Cable TV, 21 percent; VCRs, 60 percent; personal computers, 85 percent; on-line databases, 114 percent, and videotex services, 135 percent.

Cable TV is doing phenomenally well right now and continuing to grow, says Pollock, because it's meeting the needs of a demanding public: "It's in tune with all the things we know about marketing and giving people more choices, meeting their segmented choices."

It's a similar thing with VCRs, he notes. "The theme is one of intelligent choice."

Why the bad news for network television? "It's the same message that's being sent to Detroit. Unless they're willing to make the kind of cars people want, people won't buy those cars."