An EEG measures the brain’s electrical activity, while an MRI creates detailed images of the brain’s structure. Because EEGs and MRIs answer different questions, a neurologist may recommend one or both, depending on your symptoms and what they suspect is going on.
At Neurological Medicine, P.A., our Maryland neurology practice provides comprehensive neurological care and in-office neurodiagnostic testing. Our goal is to help you understand the cause of your symptoms. The right test depends on a clinical evaluation, so learn why you might need both an EEG and an MRI.
Note: Content on neuromedpa.com is not doctor’s advice and should not be taken as such. Always contact your primary care doctor for medical services, diagnosis, treatment, lifestyle adjustments, and more.
What Is an EEG?
EEG stands for electroencephalography, or electroencephalogram. Electrodes placed on the scalp pick up electrical activity produced by brain cells. The results appear as patterns, or waveforms, that a neurologist interprets. An EEG mainly shows how the brain functions. It doesn’t give a detailed picture of brain anatomy. Our EEG brain wave testing in Maryland uses scalp electrodes to monitor brain activity.
What Conditions Can an EEG Help Evaluate?
EEGs are often used when a neurologist is looking into different types of seizures, epilepsy, or certain sleep disorders. EEGs show changes in brain function linked to other neurological conditions, so EEG testing may help evaluate the risk or severity of headaches, stroke, and dementia.
What Is an EEG Like for the Patient?
An EEG is noninvasive and painless. Electrodes are placed on your scalp, and you’ll need to stay relatively still during the test. Some tests use flashing lights or other stimuli to see how the brain responds. The full appointment generally takes about an hour, including electrode placement. Ask your care team what to expect.
What Is an MRI?
MRI stands for magnetic resonance imaging. It uses magnetic fields and radio waves to produce detailed images of the brain. An EEG focuses on function, while an MRI focuses on structure. An MRI can reveal structural abnormalities that may contribute to neurological symptoms.
What Conditions Can a Brain MRI Help Identify?
A brain MRI can help identify tumors or lesions, stroke-related changes, structural abnormalities, and other problems affecting brain tissue. For seizures and epilepsy, it can help find structural causes such as tumors, vascular abnormalities, or other changes in the brain.
What Is an MRI Like for the Patient?
You’ll lie on a table that slides into the scanner. The machine makes loud sounds, and staying still is important. Some exams use contrast, depending on the question being asked. Before your MRI, talk with your provider about any implants, metal devices, claustrophobia, or other concerns.
EEG vs. MRI: Key Differences at a Glance
| EEG | MRI | |
|---|---|---|
| What it measures | Electrical activity in the brain | Brain structure |
| What it shows | Patterns and waveforms that reflect brain function | Detailed images of tissue and anatomy |
| Common uses | Seizures, epilepsy, sleep disorders | Tumors, stroke changes, structural causes of seizures |
| Patient experience | Electrodes on the scalp, about an hour | Lying in a scanner with loud noises |
EEG vs. MRI for Seizures and Epilepsy
Seizures are one of the most common reasons EEGs and MRIs get ordered, so it helps to understand what each test tells a neurologist. It is important that if your doctor or care team has ordered a variety of tests, you schedule all tests to get all the required information for a proper diagnosis and treatment plan.
What Does an EEG Tell a Neurologist About Seizures?
An EEG looks for abnormal electrical activity. It can show seizure activity and patterns, and it may help characterize suspected epilepsy.
What Does an MRI Tell a Neurologist About Seizures?
An MRI looks for structural abnormalities that could contribute to seizures. It can identify lesions, tumors, vascular abnormalities, or other structural changes, and it gives a clearer view of the physical condition of the brain.
Why Might Someone Need Both an EEG and MRI?
An EEG and an MRI answer different questions. One looks mainly at electrical activity, and the other looks mainly at brain structure. Using both can give a more complete picture when it’s clinically appropriate. When used together, a doctor can evaluate what is causing a seizure and what type of seizure activity is happening.
What Other Neurological Tests Might Be Recommended?
EEG and MRI are only two of the tools used in a neurological evaluation. Neurological Medicine, P.A. offers several in-office neurodiagnostic studies, including:
- Memory and cognitive testing
- EMG and nerve testing
- Sudo Scans
- Computerized dynamic posturography
- Visual evoked potential testing
- Transcranial Doppler ultrasound
- Carotid Doppler ultrasound
- Vestibular testing
Our approach combines neurological evaluation with the right diagnostic testing so patients can better understand what’s behind their symptoms. You can see the full list on our neurology services page.
When Should You Talk to a Neurologist About Neurological Testing?
Consider scheduling an evaluation if you have:
- Unexplained seizures or seizure-like episodes
- Recurrent episodes of loss of awareness
- New or unexplained neurological symptoms
- Persistent dizziness or balance problems
- Significant changes in memory or thinking
- Unexplained weakness or changes in sensation
- Symptoms that concern your primary care provider
Not everyone with these symptoms needs an EEG or MRI. The neurologist decides whether testing is appropriate after reviewing your symptoms and medical history. You can also browse our list of neurological conditions we treat.
Get Answers About Your Neurological Symptoms With Neurological Medicine, P.A.
If you’re dealing with unexplained neurological symptoms, speaking with a qualified medical professional is a good first step. Our team offers comprehensive neurological services and can discuss whether an EEG, MRI, or another diagnostic test may be appropriate.
We have offices in Greenbelt and Laurel, Maryland. Our Greenbelt office is at 7500 Hanover Parkway, Suite 201, and our Laurel office is at 7350 Van Dusen Road, Suite 430. Both are open Monday through Friday, 7 AM to 4 PM.
Request an appointment today, or call us at (301) 982-7944.
Frequently Asked Questions
Is an EEG the Same as an MRI?
No. An EEG measures electrical brain activity, while an MRI produces images of brain structure. Both provide doctors with different information, and they are not interchangeable tests.
Which Test Is Used for Seizures: EEG or MRI?
Both an EEG or an MRI may be scheduled for seizure symptoms, diagnosis, or treatment. An EEG displays the seizure activity, while an MRI may explain why a seizure is happening.
Does an EEG Show Brain Damage?
No, an EEG will not show brain damage. An EEG measures electrical activity. It isn’t designed to provide detailed structural images of brain damage, which is why an MRI or other neurological tests may be requested.
Does an MRI Show Brain Activity?
An MRI does not show brain activity; instead, an MRI shows the brain structure, including any evidence of tumors or abnormalities.
Are EEGs and MRIs Safe?
Both tests are generally noninvasive. Be sure to share relevant medical information with your provider and follow their instructions.
How Long Does an EEG Take?
Our EEG appointments generally take about an hour, including electrode placement and monitoring.
Can You Have an EEG and MRI on the Same Day?
That depends on your circumstances, scheduling, and the providers involved. Ask your care team.
Neurological Medicine, P.A.
Neurological Medicine, P.A., provides comprehensive diagnostic and treatment services to patients with conditions affecting the brain, spinal cord, nerves, and muscles. We have been serving the Prince George’s and Montgomery County area since 1975, with two offices: Greenbelt and Laurel. We offer complete adult neurological care as well as in-office neurodiagnostic studies.
