Employers who don't keep the lines of communication open during the downturn risk derailing productivity and losing top performers, a recent report suggest.

The survey, conducted among 1,000 people by Santa Barbara, California-based human resources firm Lynn Taylor Consulting, found the average employee spends 2.8 hours each day worrying about his job security. The sight of the boss's closed door when they aren't expecting it triggers fears of layoffs for 76 percent of respondents.

Lynn Taylor, the firm's owner, suggests lack of communication is the problem. The less bosses tell their employees, the more they worry, watching for non-verbal signs of layoffs instead of working.

"Managers working behind closed doors may be shutting out more than noise—they may be shutting down productivity," she said.

Robin Throckmorton of Cincinnati-based Strategic HR Inc., another human resources consulting firm, finds people often wrongly assume employees don't want to be told the bad news. In tough times, she recommends clear communication and outreach to employees for their input.

"The more you communicate, the less they need to worry about what they don't know, and the more you involve them, the more employees feel in control of their destiny," she said.

"We've never had a company [accused of] over-communicating," she added.

Throckmorton predicts once the economy turns around, companies who treated employees as disposable won't be able to hang on to their star players and will have trouble hiring.