Shares of media companies rose Wednesday as fears of an advertising slowdown based on slower economic growth abated somewhat due to a deal to avert the so-called "fiscal cliff."

Movie studio owners could also benefit from a one-year extension of certain film and TV tax credits in the budget deal passed Tuesday.

But analysts said the market's reaction was driven more by relief over the broader agreement over taxes. Without it, TV networks' advertising revenues could have been hurt.

That's because the deal stopped steep income tax hikes on many Americans that would have started this year. Tax increases would likely have hurt consumer spending, which accounts for about 70 percent of U.S. economic activity. And advertising usually tracks economic growth.

"If we went into a recession, people would be concerned about advertising," said Evercore analyst Alan Gould. "The fact that we didn't go off the cliff means advertising demand will hold up a little bit better."

In afternoon trading, media companies' stocks rose faster than the broader market.

- The Walt Disney Co. shares rose 2.3 percent to $50.93

- Time Warner Inc. shares gained 3 percent to $49.25

- News Corp. shares climbed 3.4 percent to $26.38

- Viacom Inc. shares jumped 5.5 percent to $55.64

- CBS Corp. shares were up 2.4 percent to $38.95

The Standard & Poor's 500 index gained 1.8 percent, while the tech-heavy Nasdaq composite increased 2.4 percent.