Few would doubt that those who work in call centers have extremely high-pressure jobs. Workers are on the phone for hours at a time, dealing with unseen customers, some of whom, depending on the function of the particular call center, can be angry, or at the least, impatient. Pay is often skimpy and turnover is rampant. But as industry comes more and more to depend on humans working at phone banks to dispatch functions like sales, technical support and customer service and complaints, call centers have become vital and ubiquitous. Call Center Magazine , a trade journal for the industry, estimates that as many as 3.5 million people man phones in call centers. Though some call centers, particularly those dealing with complicated financial products or sophisticated technological equipment, require workers with particular skills, many of the centers employ relatively unskilled workers.…