Working memory interference from authentication: comparing an alphanumeric password to a recognition-based graphical scheme

Abstract Authentication developers have sought to improve the memorability of passwords by replacing alphanumeric passwords with graphical passcodes. For end users, however, authentication is only a secondary task that may interrupt their working memory for a primary task. To date, little is known about the comparative impact of authentication schemes on working memory. To this end, we investigated the possible differential effects of a recognition-based graphical and alphanumeric authentication on working memory. Our controlled experiment compared recall rates for verbal, visuo-spatial, and central executive working memory tasks after authenticating with either a conventional alphanumeric password or the graphical scheme known as Use Your Illusion. Findings from a sample of thirty participants revealed that conventional passwords had a similar impact on verbal working memory compared to a graphical passcode. Contrary to theoretical predictions, recognition-based graphical authentication did not impair visuo-spatial working memory. Practical implications for the design of future authentication systems are discussed.