The common-sense notion that economic stress dents worker productivity now has some research behind it.

In a Workforce Management story about the impact of high gas prices, writer Patrick J. Kiger cites findings from Florida State University management professor Wayne Hochwarter. Hochwarter discovered that workers stressed out about gas prices tended to be “less attentive on the job, less excited about their work, less passionate and conscientious and more tense.”

It will be interesting to see if employee disengagement caused by economic anxiety drags down official U.S. productivity figures, which have grown like crazy in recent years.

According to the Economic Policy Institute, after growing 1.4 percent per year since the mid-1970s, U.S. productivity jumped to 2.5 percent a year from 1995 to 2000, and then climbed to 3.1 percent a year from 2000 to 2005.

If productivity does drop this year, it might be a sign that the trend among U.S. businesses to treat employees with minimal loyalty and generosity has a cost.

That trend can be seen in shrinking benefits coverage and stagnant overall wages. The Economic Policy Institute found that between 2000 and 2004, real median family income fell by 3 percent, or about $1,600 in 2004 dollars. U.S. companies also have shown a willingness to outsource, offshore and lay off—even in good times.

I don’t think businesses have a responsibility to provide lifetime employment. But U.S. employers are discarding workers and otherwise squeezing them in a country with a skimpy safety net. And only recently have companies really gotten off the sidelines on the issue of economic insecurity in the U.S.

U.S. employees hold relatively positive attitudes toward their employers, according to a report published this week by HR software firm Kenexa. Kenexa studied organizational confidence, defined partly as employees having confidence in their organization’s future, believing their organization is managed effectively and feeling that the products/services are of high quality. The study of more than 16,000 workers from 12 countries found that employees in India have the highest overall level of organizational confidence, followed by those in the U.S., Russia and Brazil.

I wouldn’t be surprised, though, if we see an erosion of U.S. employees’ organizational confidence and their trust in their employers–which plays a serious role in business effectiveness. Gas prices that remain near $4 in many parts of the country seem to be acting as a tipping point. They may be prompting average workers to ask hard questions about why they haven’t been sharing more in the prosperity that fast productivity growth enables.

Skeptical, financially stressed-out workers may well translate into less-productive ones.

Consider this observation from Hochwarter about high gas prices: “[T]his is happening at a time when corporate profits are down and nobody is getting the 4 to 5 percent raises of the past, which might have helped them to keep up. Instead, they’re falling behind and struggling financially, and they’re thinking, “The company isn’t stepping up and helping me out. The days of me busting my butt for my employer are over.’ “