Phorometric findings have been observed to change with stress. We test the hypothesis that postnearwork phorias predict symptoms that have been theorized to result from nearwork-induced visual stress.
We measured nearpoint and farpoint dissociated phorias in 37 unselected college students with an alternate cover test both before and after a challenging reading comprehension test. We also assessed a broad range of putative attention deficit hyperactivity disorder (ADHD)-related symptoms with the Nadeau College-level ADHD Questionnaire.
For phorias measured at nearpoint after nearwork, greater deviation from the median phoria (three exophoria) predicted higher symptoms (ρ (35) = 0.52, p < 0.001), whether that deviation was in a convergent or a divergent direction (both ρ's (18) = >0.48, p's < 0.04). An analogous result was obtained for “distance-near” stimulus accommodative convergence to accommodation (AC/A) ratios calculated from phorias, where greater deviation from median postnearwork AC/A ratio predicted higher symptoms (ρ (35) = 0.52, p < 0.0001). Symptoms did not correlate with prenearwork phorias, prenearwork AC/A ratios, or postnearwork farpoint phorias (p's > 0.05).
Phorias postnearwork, but not prenearwork, predicted self-reported ADHD-related symptoms in college students. These results link binocular imbalance immediately after sustained nearwork to symptoms theorized to result from nearwork-induced visual stress.