Non-invasive Brain Stimulation for Treating Symptomatic Convergence Insufficiency (NIBSCI)

Inclusion Criteria: Best-corrected visual acuity of > 20/25 in each eye at distance and near Exophoria at near at least 4∆ greater than at far Receded near point of convergence of > 6 cm break Insufficient positive fusional vergence at near (< 15∆ base-out blur or break) CISS score of 16 and greater for children or 21 and greater for adults Have had a dilated fundus examination within the last 12 months Informed consent and willingness to participate in the study and be randomized Exclusion Criteria: Previously treated for convergence insufficiency with home- or office-based vergence/accommodative therapy Amblyopia (> 2-line difference in best-corrected visual acuity between the two eyes) Constant strabismus History of strabismus surgery Convergence insufficiency secondary to acquired brain injury or neurological disorder Manifest or latent nystagmus Systemic disease known to affect accommodation, vergence, and ocular motility including multiple sclerosis, Graves disease, myasthenia gravis, Parkinson's disease, cerebral palsy, and diabetes Developmental disability, attention deficit hyperactivity disorder (ADHD), learning disability or cognitive dysfunction that would interfere with treatment Taking medications that can affect normal neurological function including antipsychotics, antiepileptics, and opioids Presence of metal or electronic implants in or on the body, including pacemakers