Understanding SSEP Testing: How It Works and When It’s Used
- Dr. Matt Johnson
- October 9, 2025
Somatosensory Evoked Potentials (SSEP) testing is a type of electrodiagnostic study that evaluates how well sensory signals travel through your nerves, spinal cord, and brain. It’s a noninvasive, painless way for neurologists to assess how efficiently your central nervous system is functioning.
At Neuromuscular Diagnostics in Chicago, SSEP testing is part of our comprehensive diagnostic services used to evaluate nerve and spinal cord function. By measuring how sensory signals move through the nervous system, this test helps identify issues that may be causing numbness, tingling, or muscle weakness.
How SSEP Testing Works
During the procedure, small surface electrodes are placed on your skin—typically on your wrists, ankles, or scalp. A gentle electrical stimuli is applied to activate the nerve, and the electrodes record electrical activity as it travels through the nervous system toward the brain.
The test measures how long it takes for those signals to reach your cerebral cortex and how strong they are when they arrive. If there’s a delay or a weak signal, it may indicate a problem somewhere along the pathway. Most patients find the procedure very tolerable. It doesn’t require anesthesia, involves no needles, and usually takes between 30 and 60 minutes.
Why Doctors Order SSEP Testing
SSEP testing gives neurologists and other specialists valuable information about how the sensory system is functioning. It’s often recommended when a patient has unexplained numbness, weakness, or coordination problems that could stem from nerve or spinal cord issues.
Some of the most common reasons for ordering an SSEP test include:
Evaluating spinal cord injuries or compression
Assessing nerve root problems in the neck or lower back
Supporting the diagnosis of multiple sclerosis or other demyelinating diseases
Monitoring the spinal cord during certain types of surgery
If you’re experiencing numbness, tingling, or weakness, these may also be signs you may need an EMG test to evaluate motor nerve function. Even when nerve conduction studies or EMG results are normal, SSEP testing can detect sensory pathway problems that those sensory tests might miss. Learn more about our EMG and NCV testing in Chicago and how they complement SSEP studies.
What to Expect During the Test
You’ll typically lie down in a comfortable position while the technologist performs the test. After cleaning the skin, small surface electrodes are placed on specific areas such as the wrists, ankles, or scalp. Like EMG studies, SSEP testing is noninvasive and generally well-tolerated — patients often find it even more comfortable and less painful than an EMG test.
During the study, a mild electrical pulse is applied to stimulate the nerve, and the electrodes record how your body responds. Most people describe the sensation as a light tapping or tingling. The test usually takes between 30 and 60 minutes, doesn’t require any injections or anesthesia, and you can return to normal activities right after it’s done. Because it’s safe and painless, SSEP testing offers an easy way to evaluate sensory nerve function without discomfort.
What SSEP Results Can Reveal
Normal SSEP results mean that your sensory pathways are functioning as expected. Abnormal results might point to a disruption somewhere along the nerve or spinal cord, such as inflammation, compression, or disease affecting the nerve coverings (myelin).
These insights help your doctor determine whether your symptoms are caused by a structural, neurological, or functional problem. For more in-depth clinical background, see the NLM’s overview of SSEP testing. When combined with EMG and NCV studies, SSEP testing provides a more complete picture of nerve and muscle health, helping doctors determine what EMG testing can diagnose and when sensory pathways may be affected.
How SSEP Testing Complements EMG and NCV Studies
EMG and NCV testing focus mainly on the motor and peripheral nerve systems—how well your muscles and nerves send signals. Somatosensory Evoked Potentials testing adds another layer by measuring how sensory signals move toward the brain.
By performing all three studies together, your healthcare provider can pinpoint where the issue lies, whether it’s in the peripheral nerves, spinal cord, or brain pathways. This leads to more accurate diagnoses and treatment plans.
For a closer look at how imaging supports these electrodiagnostic studies, read about our musculoskeletal ultrasound testing in Chicago, which provides real-time views of muscle and joint health.
A Key Part of Comprehensive Neuromuscular Care
At Neuromuscular Diagnostics, we perform SSEP testing along with EMG and NCV studies to provide complete, data-driven insight into nerve and muscle function. Our goal is to help healthcare providers and patients get clear answers faster, leading to better outcomes and more personalized care.
SSEP testing is a well-established method in clinical neurophysiology, helping healthcare professionals gain precise insight into sensory and spinal pathways. It plays an essential role in building an accurate treatment plan for patients with neurological or spinal disorders.
If you’ve been experiencing numbness, tingling, or weakness and your doctor recommends further testing, our Chicago-based diagnostic clinic offers SSEP, EMG, and NCV studies to help pinpoint the cause and guide treatment.
Matt Johnson, PT, DPT is the founder of Neuromuscular Diagnostics in Chicago. As one of the few licensed physical therapists in Illinois trained in advanced electrodiagnostic techniques, Dr. Johnson specializes in EMG and Nerve Conduction Velocity (NCV) testing. His clinical focus is on accurately identifying neuromuscular disorders to support effective treatment planning and improve patient outcomes.
