Just before the closing bell, JPMorgan Chase (JPM 2.51%) is down 0.30% on the day but up 5.35% so far on the week. It's been a weird two weeks, but don't expect much less weirdness anytime soon.

Central-banker mania
Two Wednesdays ago, the Federal Reserve made public its plans to wind down quantitative easing, the central bank's easy-money policy that most recently took the form of $85 billion in monthly bond purchases. And while chairman Ben Bernanke made it very clear that the wind-down would not take place unless positive U.S. economic data continued to flow in, investors freaked out anyway, sending U.S. and global equity markets plunging last Thursday and Friday.

Over on the other side of the world, China's central bank discovered the power of the spoken word, as well. As fears of a credit crunch in the Chinese economy grew after a government crackdown on shadow banking, China's central bank at first said it was content with the current level of liquidity in the system. But after that led to even more freaking out, the People's Bank of China quickly reversed itself, saying it would backstop any banks experiencing a cash shortfall.

Foolish bottom line
This is a slow news time for JPMorgan investors, and it's just as well: There's enough drama going on in the markets to make up for the lack of drama on the JPMorgan side. And after the slugging match that was Jamie Dimon's battle to retain his dual positions in the bank of CEO and COB, investors deserve a dearth of bank-centered drama.

But what about today's market correction? What's behind that? Treasury yields rose again, which may have made investors slightly bearish. Treasury yields are closely intertwined with the bond market, which, unlike the stock market, has continued a steady freak-out since the Fed's statement on QE. And savvy equity investors know it's the bond markets that can pose an existential threat to the U.S. economy, and can therefore also touch off stock market crashes: Witness the 2008 financial crisis.

But even with this mild correction in the stock market today, the Big Four banks have done surprisingly well this week, easily gaining back last week's losses, and even pushing past them:

  • JPMorgan stock dropped 2.25% last week, and has risen 5.35%.
  • Bank of America (BAC 3.35%) stock dropped 2.99% last week, and has risen 4.70%.
  • Citigroup (C 1.41%) dropped 5.01% last week, and has risen 5.80%.

With no spectacular news driving JPMorgan's share price either way, it's clear that the superbank is riding the market wave this week. Investors should greet this news with a grin, but also take it with a grain of salt: The markets are unstable. They were unstable before Ben Bernanke's statement, and they will continue to be unstable until investors feel the U.S. economy is truly on solid footing. And this won't be anytime soon: Maybe next year, when Ben Bernanke hopes unemployment will be down to 7%.

Until that happens, tune out market noise and tune into the fundamentals of the companies your invested in. That's what it means to invest Foolishly. In the long run, your portfolio will thank you, even if your stock broker won't.