New York City (CNN Business) The economic mood in the United States has changed quickly over the past six months. At the end of last year, the stock market suffered a steep decline, consumer spending tanked, and economists were forecasting a recession around the corner.

Now it's May, and by most measures, the country is back on an even keel. So why did the dark cloud pass so quickly?

Increasingly, economy watchers wonder whether uncertainty and pessimism — captured in a number of regularly released surveys that tend to be grouped under the squishy term "sentiment" — might be driving economic performance more than it used to do.

On Wednesday, Richmond Federal Reserve president Tom Barkin delivered a speech advancing this theory, noting the shock to business confidence brought on earlier this year by factors like the government shutdown and a simmering trade war. The risk: Consumers could delay big purchases and businesses could cancel expansion plans, creating a spiral that the economy couldn't self-correct.

"We could talk ourselves into a recession," Barkin said. "Some economists have studied the spread of information from a disease perspective, where the information spreads slowly at first but quickly gains steam. I would argue that in today's media climate, the 'disease' spreads faster."

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