Patients with disorders such as Parkinson's disease, Alzheimer's disease or multiple sclerosis may use a neurologist as their principal care physician. In a consulting role, a neurologist will diagnose and treat a neurological disorder and then advise the primary care physician managing the patient's overall health. For example, a neurologist would act in a consulting role for conditions such as stroke, concussion or headache. Neurologists can recommend surgical treatment, but do not perform surgery. When treatment includes surgery, neurologists will monitor surgically treated patients and supervise their continuing treatment.