Improving the reliability of eye tracking to diagnose concussion - PROJECT SUMMARY / ABSTRACT
Although concussion or mild Traumatic Brain Injury (mTBI) affects more than a million of
Americans each year, and represents a great societal burden, diagnosis is still difficult, and
reliable biomarkers are still lacking. The long-term goal is to develop measurable physiological
indicators that differ between healthy individuals, and those who sustained an mTBI. The
overall objective in this application is to increase the reliability of using eye-movements to
diagnose concussion. Circuits in the brain, devoted to vision, vestibular or oculomotor function
are so omnipresent in the brain that almost any blow to the head affects sight and eye
movements. Therefore, many researchers agree that eye tracking to monitor oculomotor
behavior shows great potential of revealing mTBI. Results from studies, using eye movements
as a biomarker to predict concussion, are encouraging, albeit not sufficiently strong to proof its
clinical utility. The central hypothesis is that the inclusion of microsaccades, the tiny eye
movements made when the gaze is fixed on a target, in the continuum of eye movements, will
provide an improved technique to diagnose concussion. The central hypothesis will be tested by
two specific aims: the first one is to increase the resolution of using eye movements to
diagnose concussion. To execute this aim, participants will be recruited among the more than
300 students of Millsaps. They will conduct a ~25-minute oculomotor task while their eye
movements are recorded. Athletes who sustain a head injury during the following sports season
will then be invited to retake the test. The second aim is to show that monitoring eye movements
are also useful in assessing to what extent an individual has recovered from injury. To execute
this aim, recovering athletes will be invited to take the oculomotor task weekly. The research
proposed in this application is innovative, because microsaccades have been ignored in eye
tracking studies; mainly because they require high frequency sampling and specialized
software. The applicant possesses both the hard- and software needed to record those elusive
eye movements and his preliminary results suggest that including microsaccades will
significantly increase the resolution of assessing oculomotor behavior. The research proposed
in this application is significant, because eye tracking has been hailed as one of the most
promising techniques to obtain a reliable and objective measurement to diagnose concussion,
and recording microsaccades has the potential to advance this technique significantly.
