Your doctor just recommended an EEG test and you're probably worried. That's normal. Many families in India delay getting an EEG because they don't know what to expect. Here's everything you need to know about EEG tests, reviewed by Dr. Abhishek Gohel and Dr. Rutul Shah, NIMHANS-trained neurologists & epilepsy specialists.
What is an EEG test?
An EEG (electroencephalogram) measures electrical activity in your brain. Think of your brain cells as tiny batteries — they're constantly sending electrical signals to communicate with each other. The EEG picks up these signals through small metal discs called electrodes placed on your scalp.
Brain cells are active all the time, even when you're sleeping. The EEG records this activity as wavy lines on a computer screen. These patterns help doctors see if your brain's electrical activity is normal or if there are any problems that might cause seizures.
Why doctors recommend EEG tests
- Epilepsy diagnosis: The most common reason — to see if seizures are caused by abnormal brain activity
- Seizure evaluation: To understand what type of seizures someone is having
- Brain injury assessment: After head trauma or stroke
- Sleep disorders: To study brain activity during sleep
- Monitoring medication: To see if anti-seizure medicines are working
How should I prepare for an EEG test?
Good preparation makes the test go smoothly and gives better results. Here's what you need to do:
Wash your hair properly
Wash your hair the night before or morning of the test with regular shampoo. Don't use conditioner, oil, gel, or any hair products. Clean hair helps electrodes stick better and gives clearer results.
Continue your medicines
Take all your regular medications unless your doctor specifically tells you to stop them. For epilepsy patients, never stop anti-seizure medicines before an EEG without doctor's permission.
Get enough sleep
For routine EEG, sleep normally the night before. However, for sleep-deprived EEG, your doctor may ask you to sleep less or stay awake all night. Follow their specific instructions.
Eat normally
Have your regular meals before the test. Low blood sugar can affect brain activity and make results unclear. Avoid excessive caffeine if you're having a sleep EEG.
What happens during the EEG test?
The actual EEG test is painless and safe. Here's exactly what to expect:
Before the test starts
- A technician will measure your head and mark spots where electrodes will go
- They'll clean these spots with a gritty paste to help electrodes stick better
- Small metal discs (electrodes) are attached to your scalp with a special paste or gel
- Sometimes an elastic cap with built-in electrodes is used instead
- The electrodes connect to wires that go to the EEG machine
During the test
- You'll lie down or sit in a comfortable chair
- The test usually takes 20-40 minutes for routine EEG
- You'll be asked to close your eyes and relax
- The technician might ask you to open and close your eyes
- You may be asked to breathe deeply for a few minutes
- Sometimes you'll look at a flashing light (photostimulation)
- You might be asked to do simple mental tasks like counting
Important to know
The electrodes only record electrical activity — they don't send any electricity into your brain. You won't feel any shocks or pain. The test is completely safe for people of all ages, including children and pregnant women.
Special types of EEG
Sleep EEG: Some brain activity only shows up during sleep. You may need to take a mild sedative or come in sleep-deprived so you fall asleep during the test.
Ambulatory EEG: This portable version records brain activity for 24-72 hours while you go about normal activities at home. It's used when seizures are rare or happen at specific times.
Video EEG monitoring: Combines EEG recording with video monitoring, usually done in the hospital for several days. This is used for complex seizure evaluation. Learn more about video EEG monitoring.
What do EEG results mean?
EEG results show different patterns of brain waves. Normal brain activity looks like smooth, regular waves. Abnormal patterns might show:
- Spikes or sharp waves: These can indicate seizure activity or increased seizure risk
- Slow waves: May suggest brain injury, infection, or other problems
- Irregular patterns: Could point to different types of brain disorders
- Focal changes: Abnormal activity in one brain area suggests problems in that specific region
But here's the thing — a normal EEG doesn't rule out epilepsy. About 20% of people with epilepsy have normal EEGs between seizures. That's why doctors sometimes need multiple tests or longer monitoring.
📞 EEG Test Availability
Routine EEG: Available at our clinic
Sleep EEG: Available at our clinic
Video EEG: Available at clinic & KD Hospital
Contact us for current rates and appointment booking.
Costs vary by city and hospital. Government hospitals typically charge less. Check if your health insurance covers EEG tests.
After the EEG test
Once the test is done, the technician will remove all electrodes and clean the paste from your hair. You might need to wash your hair again to remove all residue. If you didn't have sedation, you can return to normal activities immediately.
A trained neurologist will review your EEG recording and send a report to your doctor. This usually takes 1-3 days. Your doctor will explain the results and discuss what they mean for your treatment.
When should you get an EEG?
Consider an EEG evaluation if you or your family member experiences:
- Any type of seizure or suspected seizure
- Episodes of confusion or memory loss
- Sudden behavioral changes
- Staring spells or blank episodes
- Unexplained loss of consciousness
- Head injury with ongoing symptoms
- Family history of epilepsy with concerning symptoms
At Gujarat Epilepsy & Neuro Clinic, we provide complete EEG services including routine EEG, sleep EEG, and video EEG monitoring. Our NIMHANS-trained specialists have extensive experience in EEG interpretation and epilepsy diagnosis.