Newsmax Finance Insider and strategist Ed Yardeni observes that the current bull stock market has been plagued by 56 recurring anxiety attacks.
"I've kept a diary of these things since March 2009. There've been 56 anxiety attacks. Some were just outright corrections of 10 to 20 percent and some were mini corrections," the Yardeni Research president told CNBC’s "Halftime Report."
"I include Brexit as a mini panic attack. It only lasted two days. I started to detect after we didn't go over the fiscal cliff in 2013 that my clients were starting to get anxiety fatigue," the Newsmax Finance Insider said. "They were just tired of being scared that we were going to fall into 2008 all over again and the Fed wouldn't have any tools. Time heals all wounds," he said.
"Staying fully invested for now makes sense," he said. "It could be a melt-up scenario and then watch out for a meltdown."
On the Federal Reserve, he predicts policymakers will only "screw up" if inflation makes a surprising comeback. He said inflation is "dead."
To be sure, technology stocks sold off sharply on Friday, taking a toll on the Nasdaq and dragging on other major Wall Street indexes, which touched record highs earlier in the day.
The technology sector, which soared this year and led the market's rally, finished down 2.7 percent, after paring declines.
But financials and energy, which have lagged the broader rally this year, were strong. Energy gained 2.5 percent and financials rose 1.9 percent.
"It is a rotation today and it is out of tech into some of the other sectors," Mark Kepner, managing director of sales and trading at Themis Trading in Chatham, New Jersey, told Reuters.
"Tech has been on a tear for a very, very long ... time," said John Praveen, managing director for Prudential International Investments Advisers in Newark, New Jersey, adding that investors may be using the Cloudera quarterly results as "an excuse to take some profits."
Investors also viewed former FBI Director James Comey's testimony on Thursday as not disruptive to the stock market.
Market watchers had been concerned that the result of the Congressional hearing could derail President Donald Trump's plans for lower taxes, fiscal spending and looser regulations, which have helped drive the S&P 500 up 13.7 percent since his election.
Focus was turning to the Federal Reserve's policy meeting next week, when the U.S. central bank is overwhelmingly expected to raise interest rates.
"Markets are probably expecting that the Fed will raise rates, but they will be very gradual in removing monetary accommodation," Praveen said.
(Newsmax wires services contributed to this report).