New York (CNN Business) The Wall Street roller coaster started to climb again.

The Dow closed up 401 points, or 1.6%, on Thursday. The broader S&P 500 gained 1.9% and the Nasdaq surged 3%, its best day since March. Stocks bounced back after a sharp drop Wednesday that sent the Nasdaq into a correction

The market has slumped badly in the past several weeks, but it hasn't fallen in a straight line. Volatility is spiking, and huge sell-offs have been interspersed with big gains, including October 16's 548-point jump for the Dow and October 12's 287-point gain.

Still, the back and forth has been heaviest in one direction: down. The S&P 500 was less than a percentage point drop away from entering a correction Wednesday. Investors had been looking for strong corporate earnings to drag stocks out of the doldrums, but earnings have disappointed this quarter. That gave already nervous investors more anxiety.

"No matter how good the report or how positive the guidance, investors are looking for the exits," said Justin Walters, cofounder of Bespoke Investment Group, in a note to investors Thursday. "Companies that are reporting earnings this season are getting slaughtered."