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Electroencephalography is a non-invasive technique used to record and analyze brain activity. By placing small sensors on the scalp, Electroencephalography captures electrical signals generated by the brain, providing valuable insights into various neurological conditions. It is commonly employed in diagnosing and monitoring epilepsy, seizures, memory problems, and sleep disorders. 

Additionally, Electroencephalography aids in investigating conditions like dementia, head injuries, brain tumors, and encephalitis. This painless procedure is conducted by clinical neurophysiologists, typically during a hospital visit. With routine, sleep-deprived, ambulatory, and video telemetry variants, Electroencephalography offers a versatile tool for understanding brain function and facilitating personalized treatment plans. Discover the significance of Electroencephalography in comprehending and managing brain-related disorders.


What is an EEG?

The non-invasive diagnostic procedure known as electroencephalography (EEG) measures and logs brain electrical activity. It is a useful instrument in the study of neurology and is employed to identify and classify different neurological diseases. In order to detect and magnify the minute electrical impulses produced by the brain's neurons, electrodes are placed on the scalp during the EEG exam. 

In order to gain important insights into brain function, patterns, and disorders, these signals are then captured and evaluated. Brain traumas, brain tumors, sleep difficulties, and epilepsy are all frequently diagnosed with EEG.

EEG is a frequently utilized method because it can give precise details regarding brain activity. EEG can identify aberrant patterns or interruptions in neural activity by observing the electrical signals the brain produces. In order to diagnose and treat epilepsy, a neurological condition characterized by recurring seizures, it is therefore a crucial tool. EEG can be used to diagnose seizures, make treatment decisions, and evaluate how well antiepileptic drugs are working.

EEG is useful in evaluating sleep disorders such sleep apnea, narcolepsy, and insomnia in addition to epilepsy. EEG can detect irregular sleep patterns, changes in sleep architecture, and the underlying neurological reasons of sleep disorders by observing brain activity while a person is sleeping.

How Long Does EEG Procedure Take?

To ensure proper recording of brain activity, various measures are taken throughout the electroencephalography operation. To reduce outside influence, the patient is first placed in a quiet room in a comfortable position. The scalp is next meticulously cleansed to get rid of any oils, dirt, or debris that can impact the positioning of the electrodes or the quality of the signal. The scalp is then covered with adhesive or a special cap before tiny metal discs known as electrodes are placed there. 

Depending on the precise objectives of the EEG and the regions of the brain being assessed, different numbers and locations of electrodes are used. The patient is told to unwind and keep motionless while the recording is being done after the electrodes have been applied. The electrical impulses taken up by the electrodes are detected and amplified by the EEG machine, and are then shown as a series of waveforms on a computer screen or paper recording. The whole process is painless and usually lasts between 30 and 60 minutes.

It is crucial for the patient to participate and adhere to directions given by the medical practitioner throughout the EEG treatment. Patients are frequently instructed to close their eyes, stay still, and occasionally complete particular tasks or subjected to particular stimuli in order to elicit particular brain reactions.

To acquire more detailed data, additional tests might occasionally be run concurrently with EEG. In these studies, other physiological variables, such as heart rate, respiration, and oxygen levels, may be monitored simultaneously with video monitoring to observe bodily manifestations during seizures or other events.

Electroencephalography Risks and Side Effects

According to Karla Blocka and Daniel Yetman, undergoing an Electroencephalography (EEG) is predominantly considered safe and painless. However, certain stimuli introduced during the procedure might provoke risks, particularly in individuals with preexisting conditions like epilepsy or seizure disorders.

Risks involved include:

  • The introduction of stimuli, such as flashing lights, could potentially induce seizures in people with susceptibility.
  • A minor yet present risk exists where the stimuli might lead to an epileptic episode or other seizure activity.
  • Hyperventilation, a method used to incite irregularities, might not be suitable for everyone.
  • Individuals with histories of stroke, asthma, or sickle cell anemia may find the hyperventilation aspect risk-laden.

The technicians present during the EEG administration are well-prepared to manage any emergent situations effectively, ensuring the safety of the patient throughout the procedure.


EEG is a non-invasive, safe method that can be used on people of all ages, including newborns and the elderly. It is frequently used to assess and diagnose a variety of neurological diseases. Candidates for an EEG include people who may be exhibiting abnormal neurological symptoms such seizures, unconsciousness, memory issues, sleep abnormalities, or other symptoms. 

Additionally, it could be advised as a component of regular monitoring for people with known neurological problems. A healthcare expert, typically a neurologist or a specialized technician trained in EEG testing, decides whether to undertake an EEG.

The exact symptoms and clinical opinion of the healthcare provider determine whether a patient is eligible for an EEG. The evaluation of suspected epilepsy or seizure disorders, the assessment of changed mental status, the evaluation of sleep problems, the monitoring of brain activity during anesthesia, and the investigation of unexplained changes in behavior or cognition are some common indications for EEG.

If a child exhibits strange behaviors, developmental regressions, or other signs that could point to a neurological disorder, an EEG may be performed on them. EEG can be used to diagnose baby illnesses such neonatal seizures or find aberrant brain activity linked to birth difficulties.


There is often no particular post-procedure care or recovery period needed after an EEG. Patients can resume their regular activities right away after the non-invasive test because it doesn't require any downtime. There are no limitations on what you can eat, take, or do physically. The electrodes can be easily removed, though, by rinsing the scalp in warm water and mild soap if any adhesive or conductive gel was used to connect the electrodes. 

A neurologist or a skilled technician who has received particular training in reading EEG findings carefully examines and interprets the EEG recordings. The referring medical expert then receives the data and discusses them with the patient before making any necessary recommendations or treatment plans.


An EEG test usually yields results quickly once the procedure is finished. But to evaluate the findings, one must have a thorough understanding of neurophysiology and neurology. The electrical activity of distinct brain regions is represented by a variety of patterns and waveforms in the EEG recordings. The neurologist or technician examines these patterns in search of anomalies, distinct waveforms connected to certain illnesses, or adjustments that might point to underlying neurological issues. 

A report that comprises observations, findings, and diagnostic impressions is then created from the data. The patient will study the report with the referring healthcare provider, who will also explain the importance of the results and go over any other diagnostic procedures, therapeutic alternatives, or management strategies that might be required.

The measurement and assessment of brain function is made possible through electroencephalography, which is a useful diagnostic tool in neurology. EEG can assist in the diagnosis and monitoring of a variety of neurological diseases by capturing and evaluating the electrical activity of the brain. People of all ages can have this process because it is risk-free, non-invasive, and painless.

  • https://www.nhs.uk/conditions/electroencephalogram/