Caloric Stimulation

Written by Karla Blocka
Medically Reviewed by George Krucik, MD

Caloric Stimulation

Caloric stimulation is used to find damage to nerves in the ear. First cold and then warm water is placed into your ears to test your reaction. A calorie is a unit of heat.

Other names for caloric stimulation are caloric test, cold-water calorics, and warm water calorics.

Why Caloric Stimulation Is Performed

This test checks the function of your acoustic nerve. This nerve is involved in hearing and balance. It also evaluates the function of brain areas involved in balance.

Caloric stimulation is used to evaluate:

  • hearing loss caused by antibiotic use
  • vertigo (dizziness)
  • certain forms of anemia
  • psychological causes of vertigo
  • brain damage in comatose individuals

How Is Caloric Stimulation Performed?

Caloric stimulation is performed by inserting first cold and then warm water into the ear canals. This is done one ear at a time. The water stimulates the nerves of the inner ear.

Caloric stimulation usually follows these steps:

  • Electrodes hooked up to a computer are placed around the eyes. These are used to measure eye movement during the test.
  • A small amount of cold water is inserted into the ear canal. This changes the temperature of the inner ear and causes rapid, side-to-side eye movements called nystagmus. The cold water causes the eyes to move away from the direction of the cold water and then slowly move back.
  • Warm water is then inserted into the ear. This time, the eyes should move toward the warm water and then slowly move back.
  • Eye movements are detected by the electrodes and recorded by the computer. Sometimes the person conducting the test visually observes the eye movements.

Risks Involved With Caloric Stimulation

The test may cause some minor discomfort, especially when cold water is inserted. The test may cause brief feelings of vertigo, which can lead to nausea in some people.

Although rare, it is possible for excessive water pressure to injure an eardrum. This is more likely if the eardrum had been damaged in the past. Your doctor should check your eardrum before the procedure. This test should not be used if it is damaged.

Preparation for Caloric Stimulation

Some foods and medications can affect your test results. For 24 hours before your test, you should avoid the following:

  • large, heavy meals
  • alcohol
  • caffeine
  • sedatives
  • allergy medications

Talk to your doctor about what medications to avoid before the test. Never stop taking your medication without your doctor’s approval.

Caloric Stimulation Results

Normal Results

Normal results mean that you do not have damage to your acoustic nerve.

Abnormal Results

If your eye movements are abnormal, it may be a sign of acoustic nerve damage.

Causes of abnormal results include:

  • trauma
  • blood clots
  • atherosclerosis of the blood supply to the ear
  • some poisons
  • blood vessel disorders
  • hemorrhage
  • ear tumors
  • rubella
  • congenital disorders

Ear nerve damage can also be caused by certain medications, including:

  • diuretics
  • antibiotics
  • antimalarial medications
  • salicylates

Results from this test can also be used to rule out or confirm diagnoses, including:

  • labyrinthitis
  • Meniere’s disease
  • acoustic neuroma
  • benign positional vertigo
Was this article helpful? Yes No

Thank you.

Your message has been sent.

We're sorry, an error occurred.

We are unable to collect your feedback at this time. However, your feedback is important to us. Please try again later.

Show Sources

Trending Now

Beyond Back Pain: 5 Warning Signs of Ankylosing Spondylitis
Beyond Back Pain: 5 Warning Signs of Ankylosing Spondylitis
There are a number of potential causes of back pain, but one you might not know about is ankylosing spondylitis (AS). Find out five warning signs of AS in this slideshow.
Numbness, Muscle Pain and Other RA Symptoms
Numbness, Muscle Pain and Other RA Symptoms
The symptoms of RA are more than just joint pain and stiffness. Common symptoms include loss of feeling, muscle pain, and more. Learn more in this slideshow.
Migraine vs. Chronic Migraine: What Are the Differences?
Migraine vs. Chronic Migraine: What Are the Differences?
There is not just one type of migraine. Chronic migraine is one subtype of migraine. Understand what sets these two conditions apart.
Famous Athletes with Asthma
Famous Athletes with Asthma
Asthma shouldn’t be a barrier to staying active and fit. Learn about famous athletes who didn’t let asthma stop them from achieving their goals.
Timeline of an Anaphylactic Reaction
Timeline of an Anaphylactic Reaction
From first exposure to life-threatening complications, learn how quickly an allergy attack can escalate and why it can become life threatening.