The way a person uses a computer keyboard or mouse or taps on a smartphone screen could be a "fingerprint" to protect their data, U.S. researchers say. Engineers at Iowa State University, researching methods beyond passwords to verify computer users and protect data, report they're working on tracking individual typing patterns, movements of a mouse or use of a mobile device unique to each and every individual. Prototype software technology developed by electrical and computer engineering Professor Morris Chang and his research team can identify differences in typing rhythms, the university reported Tuesday. "These pauses between words, searches for unusual characters and spellings of unfamiliar words, all have to do with our past experiences, our learning experiences," Chang said. "And so we call them 'cognitive fingerprints,' which manifest themselves in typing rhythms." In experiments involving more than 2,000 computer users the technology recorded false acceptance and rejection rates of 0.5 percent. "Our technology is able to distinguish legitimate users versus imposters, based on the large-scale experiments we've been able to conduct," Chang said. The accuracy rates can be improved by combining analysis of typing patterns with analysis of mouse or mobile device patterns, he said.