Military Uses for Cognitive Testing

In 2008 Congress directed the Pentagon to begin pre and post deployment cognitive testing for US service members.  The main intent in the directive was a recognition that traumatic brain injury (TBI) has occurred at a much higher rate in Iraq and Afghanistan due to blast related injuries, and that the Pentagon wasn’t very well equipped to diagnose and treat non-impact “invisible” brain trauma.

Several studies have indicated TBI rates of around 20% from 2001-2009 deployments, or about 300,000 service members.  Problems with memory, focus, attention, balance and coordination are very common with blast related TBI.  Longer term PTSD symptoms like depression, low impulse control, and irritability are also likely.

To the US military’s credit, a set of computerized cognitive tests has been in various stages of development for many years, the latest version being the Automated Neuropsychological Assessment Metrics tool, or ANAM4.  ANAM has several key advantages as a baseline cognitive assessment:

  • ANAM tests have been administered over 600,000 times, which provides solid, reliable statistical averages for comparison purposes. (In the research world the term is large normative cohorts.)
  • The ANAM tool uses standardized tests on standardized delivery platforms, and has an automated, standard scoring algorithm.  When test implementation, data collection, and scoring are all standard, faith in the resulting test reports can be high.
  • ANAM has been referenced and used in many peer reviewed research journal articles, which is the “gold standard” for scientific validation.
  • Baseline and ANAM re-tests allows for individual performance histories, which is very important in determining what is “normal performance” for that person.  (This also provides the foundation for a longitudinal cognitive health record.)

There are, however, some potential drawbacks to using ANAM as a TBI diagnostic tool.  General cognitive assessment tools may not necessarily have the sensitivity to identify cognitive problems caused by blast related TBI.  There is also the general question as to whether a market-driven solution for cognitive testing tools will yield better results than a government owned and directed effort.

There are several commercial cognitive test products currently on the market, many of them targeted towards supporting clinical drug trials or evaluating concussion/TBI symptoms.  A representative list includes CANTAB, CNS Vital Signs, CogState, Brain Resource (WebNeuro), HeadMinder (CSI), and Mindstreams.

The Department of Defense faces a classic “build it in-house” or buy off the shelf dilemma.  A general cognitive assessment tool that is also diagnostically sensitive to blast related TBI probably doesn’t exist yet.  The question is will the marketplace be responsive to DoD’s requirements, or will the military go its own way on cognitive assessments?

There is at least one study underway in the Pentagon to evaluate ANAM against commercial neurocognitive assessment tools (NCAT), with the results expected sometime in 2013.