So you are going this route?
Medical Disability Exceptions to English and Civics
You may be eligible for an exception to the English and civics naturalization requirements if you are unable to comply with these requirements because of a physical or developmental disability or a mental impairment.
To request this exception, submit Form N-648, Medical Certification for Disability Exceptions. This form must be completed by a licensed medical or osteopathic doctor, or licensed clinical psychologist.
For more information, see the USCIS Policy Manual Citizenship and Naturalization Guidance.