Neurology

Electroencephalogram (EEG) Laboratory

What Is an EEG and Why Is It Performed?

An electroencephalogram (EEG) is a test designed to measure the electrical activity in the brain. EEGs are often recommended for patients who have experienced seizures or a change in mental status and are often performed annually as a monitoring tool for those who already have a diagnosis.

Adult laying on a bed and looking at a book

Contact Us

For information or to schedule, cancel, or reschedule an appointment at either our Providence or East Greenwich locations, please contact us.

Phone: 401-444-5381

Hours: Monday through Friday, 7 a.m. to 3:30 p.m.

If you need to reschedule or cancel your appointment, please give us 24 to 48 hours' notice, as appointment booking time is limited.

EEGs can become abnormal and can be helpful in evaluating brain dysfunction associated with certain conditions including:

  • Seizure disorders such as epilepsy
  • Head injury
  • Encephalitis (inflammation of the brain)
  • Brain tumor
  • Encephalopathy, a disease that causes brain dysfunction
  • Sleep disorders
  • Stroke
  • Dementia

The test is also used to monitor brain activity during procedures for patients who are being treated for brain or brain stem tumors, movement disorders, epilepsy, or trauma.

A portable EEG unit is available in the inpatient setting at Rhode Island Hospital and Hasbro Children's  Hospital for patients who cannot come to our labs.

Adult looking at a laptop

Before Your EEG

Please avoid all caffeinated products in advance of testing. Your hair should be clean and dry without any hair products such as hairsprays, mousse, or gel.

EEG Services

Routine EEG/Diagnostic EEG for Adults and Pediatric Patients

A diagnostic EEG measures brain wave activity to evaluate different areas of the brain. Patients are asked to rest quietly during the test, which can take anywhere from 20 to 190 minutes. You may be asked to open or close your eyes from time to time. In most cases, you'll also be asked to breathe in and out deeply (called hyperventilation) for a few minutes. The EEG is most helpful when it captures both wakefulness and sleep.  

Long-Term Monitoring

EEG 2-12 hours/12-26 hours

To detect intermittent seizure activity, it is often necessary to monitor your brain wave functions for up to 24 hours or more. You will also be monitored by video during the procedure. 

EEG CCTV (Televideo EEG)—Up to 6 Hours for Adult and Pediatric Patients

You must have someone accompany you and stay with you for the entire test. We allow a maximum of two visitors, depending on the COVID-19 hospital restrictions—please refer to the Lifespan visitation and Covid-19 policies

While in a bed, you will have wires placed with a sticky "gel" on your head and be monitored on a video camera for the entire duration of the test. The room has a television with a DVD player and DVD movies. You may bring DVDs to watch as well as any books, toys, or activities to keep busy—provided the activity does not feature constant motion, such as knitting, handheld video games, or tablets. 

You may also sleep during the study. You will receive a courtesy box lunch provided by the hospital cafeteria. Outside food is allowed, though it is suggested that parents or caregivers bring a cooler, as refrigeration is not available at this time. Food can also be purchased from the hospital cafeteria.

EEG Sleep-Deprived Exams

For all sleep deprivation studies, avoid taking any type of sleep medication unless advised by referring provider. 

The EEG laboratory offers the following exams:

Full Sleep-Deprived EEG: You go to bed the night before the test until 12 a.m. (midnight), staying awake from 12 a.m. until arriving at the appointed time in the EEG Lab.

Partial Sleep-Deprived EEG: You go to bed the night before the test until 3 a.m., staying awake from 3 a.m. until arriving at the appointed time in the EEG Lab.

Pediatric Sleep-Deprived EEG: You should go to bed one to two hours later than usual and get up one to two hours earlier than usual, staying awake until arriving at the appointed time in the EEG Lab.