Nielsen Monitor-Plus, the advertising intelligence service of Nielsen Media Research, reports that U.S. advertising spending through the first quarter of 2006 rose 5.6 percent over the same period last year. Internet advertising saw the biggest gains of all the media monitored with a 46.4 percent increase.

The 2006 Winter Olympics in the first quarter contributed to the increase in Network TV spending (11.1 percent), as nearly 1.1 billion dollars was spent during the games.

Advertising through the first quarter for the top 10 companies reached $4.6 billion, up 11.4 percent compared to the same time last year. Procter & Gamble Co. lead the pack with an estimated $839 million in ad spending for the first quarter of 2006.

Spending for the 10 largest categories reached $10.5 billion throughout the first half of 2006, 6.1 percent greater than the same period last year.