Towards the Personalization of CAPTCHA Mechanisms Based on Individual Differences in Cognitive Processing

  • Marios Belk
  • Panagiotis Germanakos
  • Christos Fidas
  • Andreas Holzinger
  • George Samaras
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7946)


This paper studies the effect of individual differences on user performance related to text-recognition CAPTCHA challenges. In particular, a text-recognition CAPTCHA mechanism was deployed in a three-month user study to investigate the effect of individuals’ different cognitive processing abilities, targeting on speed of processing, controlled attention and working memory capacity toward efficiency and effectiveness with regard to different levels of complexity in text-recognition CAPTCHA tasks. A total of 107 users interacted with CAPTCHA challenges between September and November 2012 indicating that the usability of CAPTCHA mechanisms may be supported by personalization techniques based on individual differences in cognitive processing.


Individual Differences Cognitive Processing Abilities CAPTCHA Efficiency Effectiveness User Study 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Marios Belk
    • 1
  • Panagiotis Germanakos
    • 1
    • 2
  • Christos Fidas
    • 1
  • Andreas Holzinger
    • 3
  • George Samaras
    • 1
  1. 1.Department of Computer ScienceUniversity of CyprusNicosiaCyprus
  2. 2.SAP AGWalldorfGermany
  3. 3.Institute for Medical Informatics, Statistics & Documentation, Research Unit HCI4MEDMedical University GrazGrazAustria

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