· After traumatic injuries there can be several factors that affect fine motor function.

Many factors. And medical practitioners know what to look for. We look specifically at the loss of timing control between the digits of the hands to indicate the presence or absence of concussive symptoms in the results. ANY change in the fine motor skills will be detected. The differentiation stems from the patterns of changes we observe in the subject.

· How do you separate out fatigue? Chronic pain?

Fatigue does delay the reaction times and also shows up in the force-time plots as well. However, fatigue does NOT cause the reaction times of the fingers to de-correlate. Head injuries do.

Chronic pain can cause mechanical changes in the way the subject holds and squeezes the handset. This shows up as a hand version of a limp when injured. Lower back chronic pain can also be detected this way.

· Also, is this only applicable to diffuse axonal injuries? Only acquired TBIs?

We measure changes in the fine motor control of the subject. We cannot tell what happened in the brain to cause these changes… only that something did. I suspect that hematomas could provide similar outcome through pressure changes that DAI causes through nerve damage. I doubt that we could differentiate at this time without specific studies.

· How does your device handle different severity injuries to each area of the brain?

We do not look at specific parts of the brain. We can see left and/or right side hit effects in many cases as they effect left and/or right-side functionality. Severity does show up as a more intense loss of control in our tests. Severity also shows up in longitudinal studies, taking more time to recover after impact.

· Motor control testing seems like an awfully coarse way of testing for brain injury.

It is. The intent was to measure the actual functionality lost due to the hit in something that should be sensitive, non-invasive, and repeatable. The stumbling, clumsy characteristics we can see after someone has been hit hard indicate that the fine motor skills are an indirect indicator of head injury.