Dmitri Poltavski, UND Dept. of Psychology, recently published an article in the July issue of Optometry & Visual Science titled “Visually Evoked Potential Markers of Concussion History in Patients with Convergence Insufficiency.”
He and his research colleagues investigated a novel cortical biomarker of concussion in patients who exhibit a common oculomotor deficit known as convergence insufficiency. Using visual evoked potential (VEP) technology, Dr. Poltavski and his team were able to discriminate between patients whose convergence insufficiency was’ related to a history of concussion and those whose oculomotor pathology was not related to previous mild traumatic brain injury. Both convergence insufficiency and magnocellular deficits are known to be frequent and persistent in persons who have sustained a concussion. Using algorithms designed to tap into two of the visual system’s major pathways, the magnocellular and parvocellular pathways, objective VEP measurements were able to identify magnocellular deficits in patients with a history of mild traumatic brain injury.
These results provide support for the development of a diagnostic method that can distinguish magnocellular deficits in individuals with a history of concussion. Since the administration of oculomotor-based therapy to individuals with a history of concussion has produced significant improvements on a number of objective visual measures, future research will examine the effects of such therapy on rehabilitation of magnocellular processing in these patients. If visually evoked potential based identification of magnocellular deficits associated with mild traumatic brain injury proves to be robust in larger population studies, this technique can become a valuable diagnostic tool for all modes of medical and rehabilitative treatment of these patients.