After starting the day with a sharp drop of 1.3%, the S&P 500 erased all of it and was up by 0.4%, with an hour remaining in trading. The Nasdaq composite also flipped to a gain of 0.6%, while the Dow Jones Industrial Average trimmed its loss to 163 points, or 0.3%, after earlier being down nearly 600 points.

AI stocks were again at the center of the action, a day after dragging Wall Street to one of its worst drops since its springtime sell-off. Nvidia, which has become the poster child of the frenzy around artificial-intelligence technology, began the day with a loss of 3.4%. It then stormed back to a rise of 2% and yanked the market in its wake.

Critics have been warning that the U.S. stock market could be primed for a drop because of how high prices have shot since April, leaving them looking too expensive. They pointed in particular to stocks swept up in the AI mania. Nvidia’s stock has more than doubled in four of the last five years, for example, and it’s still up 42% for this year so far.

Even with the S&P 500’s swings the last couple of weeks, the index that dictates the movements for many 401(k) accounts remains within 2% of its record set late last month.

“Occasional market drops are the price of the ticket for the ride,” said Brian Jacobsen, chief economist at Annex Wealth Management.

Outside of tech, Walmart edged down 0.2% after saying its CEO, Doug McMillon, will retire in January in a surprise move. He had helped the retailer embrace technology more. It had been down as much as 3.6% in the morning.

One way companies can tamp down criticism about too-high stock prices is to deliver solid growth in profits. That’s raising the stakes for Nvidia’s profit report coming Wednesday, when it will say how much it earned during the summer.

If it falls short of analysts’ expectations, more drops could be on the way. That would have a huge effect on the market because Nvidia has grown to become Wall Street’s largest stock by value. That gives Nvidia’s stock movements a bigger effect on the S&P 500 than any other’s, and it can almost single-handedly steer the index’s direction on any given day.

Another way for stock prices broadly to look less expensive is if interest rates fall. That’s because bonds paying less in interest can make investors willing to pay higher prices for stocks and other kinds of investments.

Treasury yields had been falling for most of this year on expectations that the Federal Reserve would cut its main interest rate several times this year. And the Fed has indeed cut twice already in hopes of shoring up the slowing job market.

But questions are rising now about whether a third cut will actually come to fruition at the Fed’s next meeting in December, something that traders had earlier seen as very likely. The downside of lower interest rates is that they can make inflation worse, and inflation has stubbornly remained above the Fed’s 2% target.

Fed officials have pointed to the U.S. government’s shutdown, which delayed the release of updates on the job market and other signals about the economy. With less information and less certainty about how things are going, some Fed officials have said it may be better just to wait in December to get more clarity.

In the bond market, the yield on the 10-year Treasury rose to 4.15% from 4.11% late Thursday.

Bitcoin is one of the investments that can get a boost from lower interest rates. It briefly fell below $95,000 on Friday, back to where it was in May. It had been near $125,000 only in October.

The price of gold, meanwhile, sank 2.4%. It shot to records throughout the year as investors looked for something that could protect from high inflation and big debt loads built by the U.S. and other governments worldwide. But interest rates staying higher can hurt gold, which pays its investors nothing in interest or dividends.

In stock markets abroad, indexes tumbled across Europe and Asia. South Korea’s Kospi fell 3.8% for one of the world’s largest losses.

London’s FTSE 100 dropped 1.1% amid worries the U.K. government may ditch plans to raise income taxes, which would have helped chip away at its debt load.

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AP Writer Teresa Cerojano contributed.