At the COVD 2018 Annual Meeting, Dr. Tamara Oechslin received the Vision Development and Rehabilitation (VDR) award for the best journal article of the year. The article laid the groundwork and described the methods being used to evaluate patterns of brain activation in patients with convergence insufficiency. The study used functional magnetic resonance imaging (fMRI) to measure the blood oxygen-level dependent response (BOLD) to vergence demand pre- and post-vision therapy in patients with convergence insufficiency (CI). And now, the results have been published in Optometry and Vision Science (OVS).
The subjects of this study all had symptomatic CI. After the baseline testing, they were randomized to 12 weeks of office-based vision therapy or office-based placebo (fake!) vision therapy. After that time, the preliminary testing was repeated to measure results.
Among the participants who received in-office vision therapy, their brains showed changes in activity. Some areas of the individuals’ brains showed less activation than baseline, while some showed more. There was a decrease in activity in frontal brain areas associated with attention and top-down processing. The implication is that vision therapy for convergence insufficiency decreased the degree of conscious effort required by patients to respond to a vergence demand. There was also an increase in activation in specific loci in the occipital lobe associated with driving vergence eye movements (convergence and divergence). This suggests better processing of accommodative and vergence demands after vision therapy.
This study is yet another example that confirms what clinicians have known for a very long time: patients with convergence insufficiency (and other visual deficits) must work extra hard to get their eyes to work together and process visual information. This extra effort and difficulty results in a multitude of symptoms. After vision therapy, their symptoms decrease dramatically because their brains have figured out how to process visual information with greater efficiency and to respond with greater accuracy and speed. BOLD Science is building an evidence base that cannot be denied.
Vision therapy works. It changes brains.