Boosted by the Winter Olympics on NBC, advertising spending on broadcast network TV rose 12.3 percent to $6.5 billion in the first quarter of 2006, according to data from TNS Media Intelligence.

The fastest-growing media in terms of ad spending was the Internet, which jumped 19.4 percent to $2.3 billion from a year ago. Also showing strong growth was Spanish-language media, up 14.2 percent to just over $1 billion.

Other segments of the television business showed more modest growth, with syndication up 6.2 percent to $1 billion; spot TV up 6.4 percent to $3.9 billion; and cable TV up 2.2 percent to $3.6 billion.

Overall, TNS said that first-quarter advertising spending was up 5.2 percent to $34.9 billion, short of projections. “Spending within key category segments displayed more volatility than normal,” said Steve Fredericks, president and CEO of TNS, in a statement Wednesday.

Jon Lafayette