Central banks take center stage

European Central Bank president Mario Draghi and Federal Reserve chairman Ben Bernanke will be in the spotlight this week.

NEW YORK (CNNMoney) -- As central bankers in Europe and the United States gather this week, investors around the world are wondering what the monetary authorities will do to support the global economy.

First up is the Federal Reserve, which kicked off a two-day meeting Tuesday. The European Central Bank's governing council will hold its monthly policy discussion Thursday.

Fed officials are meeting as the U.S. economy appears to have taken a turn for the worse, with a slowdown in job growth taking a toll on consumer spending.

While few expect the Fed to act this week, the central bank could extend its plan to keep interest rates near zero beyond its current 2014 forecast.

The Fed could also raise the rate on bank reserves in an effort to keep inflation in check by enticing banks to store more of their excess funds at the Fed instead of lending it out.

But analysts say the Fed will probably delay a decision on more aggressive moves, such as a third round of asset purchases, or QE3.

"I don't expect any major change in policy," said Jeffrey Bergstrand, a former Fed economist who is now a finance professor at the University of Notre Dame. "The Fed is wary of doing anything unless it sees a more substantive downturn."

Depending on how the economy fares, Fed chairman Ben Bernanke could hint at further stimulus measures at the central bank's annual symposium in Jackson Hole, Wyo., in late August. But experts say the Fed will probably not act until its September meeting, when it has had more time to assess the economy.

Once Bernanke wraps up, the ECB and its president, Mario Draghi, will be up.

"I think the more important meeting is by far the ECB," said Kathy Jones, a fixed-income analyst at Charles Schwab. "The Fed sending a signal would be nice, but the markets here are not rebelling the way they are in Europe."

Draghi raised the stakes last week when he said the bank is prepared to do "whatever it takes" to save the euro currency.

Draghi's comments sparked a rally in global stock markets and drove down borrowing costs for the governments of Spain and Italy, which had risen to record highs earlier in the week.

The ECB is widely expected to resume limited purchases of government bonds to ease the pressure on Spain and Italy. Some say the ECB could also offer European banks another round of ultra-low cost loans by launching a third Long-Term Refinancing Operation, or LTRO.

Others say Draghi and other European Union officials are working on a plan to use funds from the European Financial Stability Facility to buy bonds directly from governments in the primary market, while the ECB conducts secondary market operations.

There is also speculation that the European Stability Mechanism, a bailout fund that has yet to be fully established, could be given a banking license. In theory, this would allow the ESM to borrow money from the ECB, effectively giving it a source of unlimited funding to buy bonds.

Critics say providing additional liquidity would only reinforce the vicious cycle between banks and governments, in which banks are the main buyers of domestic sovereign debt even as they have become dependent on ECB financing.

Given the high expectations, there is a significant risk investors will be disappointed.

"The pattern we've seen in the past is that they tend to over promise and under deliver," said Jones.

-- CNNMoney's Annalyn Censky contributed