Visual Plasticity Following Brain Lesions

A. Stroke, brain tumor, or traumatic brain injury patients Who May Qualify: 1. At least 18 years of age. 2. Capable of providing willing to sign a consent form and complying with study procedures. 3. Unilateral or bilateral focal brain damage causing loss of vision. 4. At least three months post-stroke or traumatic brain injury, or a stable brain tumor within the past year. Who Should NOT Join This Trial: 1. Severe CNS diseases or disorders unrelated to the focal lesion, which could interfere with study results. 2. Severe mental health challenges that could interfere with study results, or current or recent (within the past 6 months) drug or alcohol abuse or addiction as defined by DSM-5. 3. Vision loss resulting from ocular disease or disorder. B. Healthy volunteers (age-matched controls): Who May Qualify: 1. At least 18 years of age. 2. Capable of providing willing to sign a consent form and complying with study procedures. Who Should NOT Join This Trial: 1. Any CNS diseases or psychiatric disorders (e.g., epilepsy, schizophrenia) that would interfere with study results. 2. Previous head injury. 3. Present or past (within past 6 months) drug or alcohol abuse or addiction based on DSM-5. Always talk to your doctor about whether this trial is right for you.