Neurophysiology Lab

Neurophysiology lab


Testing offered through the Neurophysiology Lab includes:

EEG (Electroencephalography):

An electroencephalogram (EEG) detects abnormalities in the brain waves or electrical activity of the brain. The EEG is used to evaluate several types of brain disorders. The test can also be used to diagnose other disorders that influence brain activity, such as Alzheimer's disease, certain psychoses, and a sleep disorder called narcolepsy. Learn more about EEGs in our Health Library.

VEEG (Video EEG/Video-EEG monitoring):

Is when a person’s brainwaves are recorded by an EEG machine at the same time the way they look (and what they are doing) is recorded on video. This is the best way to learn about seizures and where they come from in the brain. This test is often performed on a patient admitted to the epilepsy unit and monitored over a period of time.

Ambulatory EEG monitoring:

Is when an EEG test is performed on the patient outside the hospital through the use of small portable unit. Patients may walk around and carry on with their daily life as usual while the EEG is recording. These tests usually are done for 24-48 hours.

Single photon emission computed tomography (SPECT):

SPECT is a test that looks at blood flow in your brain to try to find out what area of the brain is causing the seizure. A small amount of radioisotope is given for this test to help highlight the area of increased blood flow in the brain. During a seizure, the blood flow increases in the area of the brain where the seizure begins. In between seizures the blood flow can be less than normal at the site where seizures begin. A SPECT scan can be done during a seizure (Ictal SPECT) and when you have not recently had a seizure (Interictal SPECT). The two scans are compared to examine the difference in blood flow.


Named after the neurologist who perfected the procedure, is performed to establish which cortical functions are localized to a particular hemisphere of the brain.

Evoked Potentials (EP):

Studies of visual, auditory and sensory conduction through the brain and spinal cord. These tests are primarily used to measure the response to visual, auditory, and electrical stimuli. Learn more about EPs in our Health Library.

PET (Positron Emission Tomography):

The patient is given a small dose of glucose (sugar) with a radioisotope for this procedure. The PET scan can also be done either during a seizure (Ictal PET) or when you have not recently had a seizure (Interictal PET). PET looks at how your brain uses sugar and makes images that show what areas of the brain are active either during a seizure or in between seizures. An EEG is done at the same time as the PET. You will go to the EEG lab first before going to radiology.
Please do not eat 6 hours before the PET study. Learn more about PETs in our Health Library.

Vagus Nerve Stimulators

The Vegas Nerve Stimulator (VNS) system is used in patients who have uncontrolled seizures which have not responded well to treatment. The VNS can be used in addition to other treatment options such as medications, the Ketogenic diet, or epilepsy surgery. The VNS system provides a mild electrical stimulation from a generator which is put in the chest. This stimulation is sent to the brain via a lead that is attached to the vagus nerve. This usually occurs every 3-5 minutes for 30 seconds and the settings may be changed by your epilepsy provider.


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