A woman comes to you, a psychiatrist, complaining of being depressed, tired and irritable. She also has frequent headaches. Lately she has noticed some numbness, tingling in her hands and feet, and muscles weakness that makes walking difficult. She also has an odd lesson, but thinks her general depression makes her more susceptible to injury. This woman has been taking high does supplements of certain b vitamins because she has been told they will help with her PMS. What vitamin is she deficient in? What is the toxic level?