Ralph F. Jozefowicz, MD, FAAN, responds

If you are experiencing a symptom such as muscle weakness, numbness, headaches, dizziness, or seizure, your doctor is likely to refer you to a neurologist, a physician who specializes in diseases and complications of the brain and central nervous system. During a typical exam, which lasts about an hour, neurologists test the functioning of the nervous system, a complex entity that consists of the brain, spinal cord, cranial nerves, and peripheral nerves.

Like most doctors, neurologists wear white coats. Unlike most other doctors, we often have an array of small instruments—a lightweight percussion hammer, a tuning fork, and a flashlight—at hand. We use these throughout the exam to test reflexes and perception of vibration and to examine the eyes. Not all exams are identical; they may vary according to your symptoms. In general, this is what you can expect:

First, we'll conduct a full medical history, which lasts 15 to 20 minutes, during which we will ask about all your symptoms, how long you've had them, and if they've worsened over time. We then do an assessment of your mental status, including a memory test. We may ask you to remember three things—a clock, a car, and an apple, for example—and to repeat them later. We may ask you to count down from 100 by sevens (100, 93, 86, etc.), to name objects, and to do some reading and writing.

From there, we may test the 12 cranial nerves that connect your brain to different parts of your head and neck and control your senses, facial muscles, and glands. To test your sense of smell, for instance, we might ask you to sniff a bar of soap or a vial of coffee grounds and identify the odor. To test your vision, we ask you to read an eye chart. We also use an ophthalmoscope and flashlight to examine your eyes. To check your visual fields, we'll wave fingers past your eyes.

We assess reflexes with the rubber percussion hammer and hearing with a tuning fork—which is also used to see how well you perceive vibration in your limbs. To test sensation, we may prick you gently with a safety pin. To check coordination, we ask you to tap your fingers or foot quickly or touch something (like your nose) with your eyes closed. The last thing we ask you to do is walk normally first and then on your heels and toes to test your gait.

Depending on your symptoms, we may order additional tests: bloodwork, to check for immunologic and endocrine disorders, and imaging (such as MRIs or CT scans) to look for brain lesions or problems with blood vessels, spinal nerves, or discs.

If you've had seizures, we may order an electroencephalogram (EEG), a procedure that involves placing electrodes on your head to assess electrical activity in the brain. If you're experiencing limb numbness or muscle weakness, we may perform a nerve conduction study and an electromyogram (EMG) to check communication between nerves and muscles. During this test, electrodes are attached to your skin, and we measure muscle activity in response to electrical stimulation of a peripheral nerve.

In preparation for your first visit, write a detailed description of your symptoms and when they began, as well as your family medical history and a list of all your medications, including vitamins and supplements. On the day of your appointment, bring these notes along with your ID and insurance card. You also may want to bring a family member, caregiver, or friend who can help you fill in your medical information and take notes during the appointment.