Evoked potentials are diagnostic techniques that, by means of sensitive stimuli and the recording of brain responses obtained by the physician specialized in Clinical Neurophysiology, assess the integrity of the stimulated sensitive pathways.
What are evoked potentials used for?
These diagnostic tests are recommended for patients suffering from some of these pathologies:
- Optic neuritis
- Multiple sclerosis
- Hearing loss
- Cranioencephalic traumas
- Spinal cord injuries
- Neuropathies
- Cognitive impairment (dementia or Alzheimer’s disease)
- Psychic affections (depression)
Types of evoked potentials
There are several types of evoked potentials depending on the pathology and the area to be explored:
- Visual: the patient receives stimuli from a screen (intermittent flashes of light) to study how the brain processes them.
- Auditory brainstem: the stimuli are transmitted to the ear through headphones.
- Somesthetic: the patient receives small electrical cramps in the upper limbs (arms), lower limbs (legs), trigeminal nerve area (responsible for touching the face), pudendal nerve (in the pelvic region) or endogenous to study how the patient receives tactile stimuli.
Evoked potentials test
Before undergoing the test, the patient must wash the parts of the body where the electrodes will be applied, but may not apply hairspray or cologne or products of this type. The test, which lasts approximately 30 minutes, is completely painless.