Slow and steady wins the race, but a bird in the hand is worth two in the bush. Those dueling proverbs sum up the investing mind.

When you imagine choosing between making a quick buck or growing rich later, you know the right answer: Be patient and hold out for the bigger gain. But as soon as you face a real rather than an imaginary choice, the fast money seems irresistible.

New discoveries in neuroscience labs are helping to explain why it's so hard to resist the allure of instant gratification. It turns out that your brain is much more aroused by $1 today than by $1 tomorrow. And $1 six months from now barely registers.

Only the promise of a much bigger reward later can fire up your brain the way an immediate score does. No wonder it's hard to save instead of spend and, when you do save, to think long term; the average holding period for a stock, among individual and professional investors alike, is just over 11 months.

And the temptation to buy dotcom stocks in 1999, energy stocks in 2005, real estate in 2006, emerging markets in 2007 or gold right now - what's hot when it's hot - is overpowering for many people, no matter how often they've been burned before.

A sip now or a slurp later?

Recent experiments conducted independently by three teams of researchers at leading universities have

NEW YORK (AP) -- Oil prices jumped to a new record above $106 Friday but settled lower, extending their recent pattern of choppy trading after a weak jobs report convinced many traders that the Federal Reserve's interest rate cutting campaign will continue.

Employers cut 63,000 jobs in February, the biggest drop in five years, the Labor Department said. Investors can react to such news in one of two ways: by selling on the prospect that the economy, and demand for oil, is cooling, or by buying on a conviction that bad economic data makes it more likely the Fed will cut rates.

On Friday, investors engaged in a little of both, sending oil prices down more than a dollar at one moment, and propelling them to new records the next.

"The higher the market goes, the more volatile it becomes," said Darin Newsom, senior analyst at DTN in Omaha, Neb. "Does it mean that the rally is over? No."

Light, sweet crude for April delivery fell 32 cents to settle at $105.15 a barrel on the New York Mercantile Exchange. But prices fluctuated widely, setting a new trading record of $106.54 and falling as low as $103.91.

At the pump, meanwhile, gas prices extended their march toward new records, rising 0.4 cent to a national average of $3.189 a gallon, according to AAA and the Oil Price Information Service. Gas prices