Effect of Cognitive Depletion on Password Choice

  1. Lookup NU author(s)
  2. Dr Thomas Gross
  3. Dr Kovila Coopamootoo
Author(s)Gross T, Coopamootoo K, Al-Jabri A
Publication type Report
Series TitleSchool of Computing Science Technical Report Series
Report Number1496
Full text is available for this publication:
Background. The Limited Strength model [3] of cognitive psychologypredicts that human capacity to exert cognitive effort is limited andthat decision making is impeded once high depletion is reached.Aim. We investigate how password choice differs between depleted and undepleted users.Method. Two groups of 50 subjects each were asked to generate a password. One group was cognitively depleted, the other was not. Passwordstrength was measured and compared across groups.Results. Using a stepwise linear regression we found that password strength is predicted by depletion level, personality traits and mood, with an overalladjusted R2 = :206. The depletion level was the strongest predictor of password strength (predictor importance :371 and p = :001). Participants with slight effortful exertion created significantly better passwords than the undepleted control group. Participants with high depletion created worse passwords than the control group.Conclusions. That strong depletion diminishes the capacity to choose strong passwords indicates that cognitive effort is necessary for the creation ofstrong passwords. It is surprising that slight exertion of cognitive effort prior to the password creation leads to stronger passwords. Our findings open upnew avenues for usable security research through deliberately eliciting cognitive effort and replenishing after depletion and indicate the potential of investigating personality traits and current mood.
InstitutionSchool of Computing Science, University of Newcastle upon Tyne
Place PublishedNewcastle upon Tyne
ActionsLink to this publication