TBI affects working-age population. People with mTBI often complain about having problems with reading, yet must spend extended time reading each day to accomplish work and personal goals. The few studies that have examined reading in mTBI employed short text; we hypothesized that sustained (≥20 minutes) reading would induce fatigue, affecting oculomotor performance, including accommodation.
Methods: Native English speaker adults (4 with mTBIs and 4 controls) were recruited. All had normal acuity and no ocular pathology. Participants completed a questionnaire regarding their reading habits and the Convergence Insufficiency Symptom (CIS) survey.
For the reading studies, participants read a text from IReST while their accommodation was measured using a PlusOptix PowerRefractor 3. This was done before and after sustained reading for comprehension.
All mTBIs reported reading several hours a day. TBIs scored much higher (reported more problems) in the CIS. IReST and sustained reading time were correlated. Reading got slower post versus pre sustained reading for IReST. TBIs showed a larger change in accommodation which was correlated with their CIS score. The change in accommodation was related to change in reading time: those who accommodated less read more slowly during the post IReST.
Our results suggest that inefficiency in both accommodation and convergence contribute to reading problem in TBIs.