Eye Tracking Technology to test Traumatic Brain Injury
In fact, no single test can make the decision as to how severe a TBI is but rather a multitude of tests.
The Visual Tracking test is just one test. In the test, the subject is asked to track a lighted object and a camera picks out a thousand or more pieces of data. The results can tell the degree of brain injury.
The test is being used by the US military to test soldiers who suffer from various degrees of brain injury. The test will hopefully replace the stationary visual testing, which took three minutes to do as compared to the new test, which will take only a few seconds to do.
In addition, the Eye Tracking test picks up at least a thousand points while the stationary test picks only a few points. It is hypothesized that those with a traumatic brain injury show deficits in the usual smooth pursuit because these tasks are associated with the cognitive function that is impaired.
It depends on the white matter connection to multiple cerebral areas and cerebellar areas. In a study of 21 patients with traumatic brain injury, there were twenty-six control subjects; the traumatic brain injury patients displayed decreased target prediction and greater eye position error with the variability of eye position. This was associated with decreased target prediction. In all subjects, the average target prediction, eye position variability and eye position error were correlated with decreased attention to task and difficulties with executive function.
No differences were noted between the groups on the California Verbal Learning Test, average eye gain, Wechsler Abbreviated Scale of Intelligence or intra-individual eye gain variability. What this suggests is that the deficits observed were not the result of oculomotor problems or reduction in IQ.
The correlation between eye testing and CVLT-II scores means that the eye test may be a sensitive predictor of cognitive function, including attention and executive function.
It seems that the use of Eye Tracking is a good way to measure the degree of impairment from traumatic brain injury.