An EEG records the electrical activity of the brain through small metal discs placed on the scalp. It is recorded for 20 to 40 minutes as a routine test, after sleep deprivation, or over days with video in a monitoring unit.
It helps to confirm epilepsy, classify the seizure type and guide treatment. A normal EEG does not rule epilepsy out, and an abnormal one does not prove it; the diagnosis rests mainly on the description of the events.
What EEG (Electroencephalography) shows
The tracing shows background rhythms and how they change with eye opening, drowsiness and sleep. The neurophysiologist looks for epileptiform discharges such as spikes and sharp waves, whether they are generalised or come from one region, slowing that suggests a local or widespread brain disturbance, and patterns typical of specific syndromes such as childhood absence epilepsy. Video telemetry captures actual events so that epileptic seizures can be told apart from fainting, sleep disorders and functional seizures.
When EEG (Electroencephalography) is recommended
- A first unprovoked seizure or suspected epilepsy
- Classifying epilepsy to choose the right medication
- Repeated blackouts or episodes of altered awareness of uncertain cause
- Assessment before epilepsy surgery, using prolonged video EEG
- Unexplained confusion or reduced consciousness in hospital
- Some sleep and developmental disorders in children
Limits and situations where another test is better:
- It is not useful for headaches, dizziness or simple faints
- It does not show brain structure; MRI does that
- A single routine recording misses abnormalities in roughly half of people with epilepsy
How to prepare
- Wash your hair and avoid gels, oils or sprays
- Take your usual medicines unless told otherwise
- For a sleep-deprived EEG, stay awake for most of the previous night as instructed
- Bring a witness description or a phone video of an episode
What happens during the test
A technician measures your head and attaches about 20 electrodes with paste. You sit or lie quietly, open and close your eyes, breathe deeply for 3 minutes and look at a flashing light. These manoeuvres can occasionally bring on a seizure, which staff are trained to manage. Nothing is felt from the electrodes. The appointment lasts about an hour.
Results and next steps
A neurophysiologist reports the recording, usually within 2 to 5 working days; video telemetry takes longer. Your neurologist combines it with your history and MRI to decide whether treatment is needed and which drug fits the seizure type.
- Test time: About 1 hour; telemetry 2 to 7 days
- Results ready: 2 to 5 working days
- Back to everyday activity: None
Safety and risks
- Paste residue in the hair and mild skin irritation
- A small chance of a provoked seizure during deep breathing or flashing lights
- Tiredness after sleep deprivation; do not drive home
Arranging EEG (Electroencephalography) in Türkiye
A routine EEG alone does not justify a flight. Travel makes sense for a full epilepsy review, with EEG, epilepsy-protocol MRI and specialist opinion together, or for several days of video telemetry when surgery is being considered. Check the rules on flying and driving after a recent seizure.
Send your previous reports and the question you want answered and a Clinic-Y coordinator replies within 24 hours with suitable teams and written, all-inclusive proposals side by side. Reviewing your case is free.
الأسئلة المتكررة
Can the machine read my thoughts or give shocks?
No. It only records tiny signals that the brain produces. Nothing is sent into the head.
Should I stop my epilepsy tablets first?
Never stop them on your own. Medication is only reduced under supervision in a monitoring unit.
Can children have it?
Yes. It is harmless, and recordings during natural sleep are often the most informative in young children.