An n-back task, or Continuous Performance Task, presents a continuous sequence of numbers to a user and requires them to repeat the number that is n back along the sequence from the number currently being presented. n can signify any number back, and the task can be altered to be easier or more difficult for the subject carrying it out. n-backer presents the task automatically and is designed to be used in conjunction with testing for assistive technology for people with cognitive and physical impairments. The intention is that it will simulate the impairment and indicate to the tester any difficulty the groups they are designing for may have with the technology.
Part of the VERITAS project
Download: N-Backer Software
This software was previously available at: http://irgen.ncl.ac.uk/go/nback/