Evoked potentials: an objective assessment of the work of the nervous system

When standard examinations are not enough.

We are expanding the possibilities of neurological diagnostics in our medical center of Dr. Bersenev, introducing the method of Evoked Potentials (EP).

Many patients are faced with a situation where a standard EEG, MRI or an ophthalmologist’s examination shows “normal”, but complaints about vision, hearing, memory or “fog in the head” remain. Why does this happen? Because MRI shows the anatomical structure of the organ (presence of a tumor, consequences of trauma), but does not always allow to assess its function – that is, how quickly and qualitatively the nerve signal passes from the receptor to the brain.

What are evoked potentials in simple terms?

Evoked potentials are a method of functional diagnostics that tracks the path of a nerve impulse from a receptor (eye, ear) to the cerebral cortex.

Imagine that a nerve is an electrical wire.

• MRI shows whether its structure is preserved;
• Evocated potentials make it possible to evaluate how the signal passes through it and whether there are delays.

It helps to obtain objective information in situations where other methods do not give a complete answer, and to provide the doctor with data for making a clinical decision.

We conduct three main types of research.

Visual evoked potentials (VEP)

This study evaluates the work of the entire visual pathway: from the retina of the eye through the optic nerve to the occipital lobe of the brain, where visual perception is formed.

When is it necessary?

VEP is recommended in the following cases:

• A sharp decrease in vision in the absence of ophthalmic pathology;
• Suspicion of multiple sclerosis (signs of demyelination);
• Neuritis, traumatic injuries or atrophy of the optic nerve;
• Unexplained loss of visual fields or suspicion of cortical visual disturbances.

The method helps to determine at what level the disturbance occurs – in the eye, in the optic nerve or in the structures of the brain.

Find out the cost and sign up for Visual Evoked Potentials (VEP)

Auditory or acoustic evoked potentials (AEP)

This method allows objective assessment of hearing function even in patients who cannot provide feedback (for example, in infants or people with speech disorders).

The study analyzes the passage of a sound signal along the auditory nerve and brain stem structures.

To whom is this examination recommended?

• For children: with speech delay, psychomotor development, autistic spectrum disorders or suspected hearing loss;
• Adults: with hearing loss of unclear etiology, tinnitus, dizziness;
• SVPs are also used for dynamic monitoring in multiple sclerosis or after neuroinfections.

More details about Auditory evoked potentials and preparation

Cognitive evoked potentials (CEP)

This is an advanced method of assessing the functional state of the brain.

While standard EEG captures electrical activity at rest, CVPs demonstrate how the brain processes information: perceives stimuli, sustains attention, and engages memory.

Main indications for carrying out:

• Complaints about deterioration of memory, attention, concentration;
• Feeling “foggy in the head”, reduced speed of thinking (especially after COVID-19 or injuries);
• Evaluation of cognitive functions when neurodegenerative processes are suspected;
• Control of the condition after strokes or craniocerebral injuries;
• In children: with attention deficit disorder (ADHD) and delays in the development of school skills.

KVP help to distinguish organic disorders of cognitive functions from functional or psycho-emotional factors within the framework of a comprehensive examination.

Sign up for diagnostics of Cognitive evoked potentials

Why is this important?

The implementation of the technique of evoked potentials allows our neurologists to see a complete picture of the functional state of the nervous system. It is a safe, non-invasive method that does not involve radiation exposure and is suitable for both adults and children.

Ready to check the functioning of your nervous system? Make an appointment to determine which type of diagnosis is right for you.