Short answer

ABR—auditory brainstem response—is an objective test that records the auditory system’s electrical response to sound using surface electrodes placed on the skin. A child does not need to press a button, raise a hand or tell the clinician when a sound is heard.

This is particularly useful for infants and young children who cannot yet complete reliable behavioural pure-tone testing. Depending on the protocol, ABR can help assess auditory-pathway function through the brainstem and provide frequency-specific estimates of hearing sensitivity.

ABR is not a stand-alone answer to every question about hearing. Results are interpreted together with OAE, tympanometry, sometimes ASSR, bone-conduction measures and, later, behavioural audiometry.

What does ABR actually record?

During ABR, controlled sounds are delivered through insert earphones or headphones. Surface electrodes on the forehead and near the ears record very small bioelectrical responses generated by the auditory system after each sound.

Kazakhstan’s current audiological-care rules define short-latency auditory evoked potentials as bioelectrical potentials arising in structures of the auditory system, predominantly the brainstem, in response to sound and recorded from the surface of the head.

In other words, ABR does not “take a picture of the ear,” and it does not directly measure how a child understands language. It records a physiologic response of the auditory pathway to controlled acoustic stimulation.

What happens during the test?

A typical diagnostic ABR appointment includes several steps:

The skin is cleaned where the electrodes will be attached.
Small surface electrodes are placed on the forehead and around the ears.
Insert earphones or headphones deliver the sounds.
The child needs to remain as calm and still as possible; infants are often tested while asleep.
Sounds at different intensities—and, for diagnostic testing, different frequencies—are presented.
The audiologist evaluates whether responses are repeatable and reduces the level to identify the lowest level at which a reliable response can still be recorded.

The electrodes do not deliver electrical stimulation. They only record naturally occurring electrical activity in response to sound.

Why does sleep matter?

ABR signals are very small. Movement, crying, muscle tension, active sucking and frequent blinking create electrical artefact that can make the recording difficult to interpret.

For this reason, very young infants are often tested during natural sleep. ASHA notes that infants under about three months can frequently be assessed while naturally asleep or resting quietly. Older or more active infants may sometimes need a different clinical approach. Sedation or anaesthesia, when clinically indicated, is a separate medical procedure and should never be improvised at home.

The goal of preparation is not to exhaust a baby at any cost. It is to create safe conditions in which the baby can fall asleep naturally and remain still long enough for a clean recording.

What does an “ABR threshold” mean?

For threshold estimation, diagnostic ABR uses frequency-specific stimuli such as tone bursts or chirps. The stimulus level is reduced until the lowest repeatable response is found.

That lowest repeatable level becomes the basis for an electrophysiologic estimate of hearing sensitivity.

Two important caveats matter for parents.

First, ABR results are not always numerically identical to a mature behavioural audiogram. Method-specific correction factors may be used depending on frequency, stimulus, equipment and protocol.

Second, an electrophysiologic threshold is not a direct measure of how a child understands words, follows speech in noise or uses hearing in everyday life.

Air-conduction and bone-conduction ABR

If air-conduction responses are elevated, the clinician may need to determine whether the problem is mainly related to sound transmission through the outer/middle ear or to the inner ear/auditory pathway.

Bone-conduction ABR can help with that question. A bone oscillator delivers vibration through the skull, partly bypassing the outer and middle ear.

Comparing air- and bone-conduction responses can help characterize a conductive versus sensorineural component. The interpretation is still made together with tympanometry, otoscopy, OAE and other findings.

Can ABR prove that hearing is “normal”?

ABR can provide crucial information, but the statement “normal ABR means hearing is completely normal in every way” is too broad.

Standard ABR does not directly measure:

speech understanding;
speech-in-noise performance;
language development;
auditory attention;
everyday listening behaviour.

The result also depends on which frequencies and stimulus levels were actually tested. Automated screening ABR and a full frequency-specific diagnostic ABR do not provide the same amount of information.

Why are OAE and tympanometry still useful after ABR?

Because each test asks a different question.

OAE

Otoacoustic emissions assess outer-hair-cell/cochlear function. They do not provide a complete estimate of behavioural hearing thresholds and do not assess the entire neural pathway.

Tympanometry

Tympanometry evaluates middle-ear status and eardrum mobility. Middle-ear fluid or other conductive problems can affect air-conduction ABR and OAE results.

ASSR

ASSR can add frequency-specific objective information when a broader threshold picture is needed. It does not automatically replace ABR, OAE or immittance testing.

The value comes from the test battery, not from declaring one test “best.”

Why is ABR important in auditory neuropathy?

When auditory neural synchrony is in question, ABR becomes particularly important alongside OAE.

NIDCD describes the classic auditory neuropathy pattern as preserved or normal OAE with an absent or markedly abnormal ABR. The outer hair cells may still be functioning while neural transmission is disrupted.

That is why “OAE present = the entire hearing pathway is normal” is unsafe wording.

Why is behavioural audiometry still needed later?

For a period of infancy, electrophysiologic results may provide the best available estimate of hearing sensitivity. Once a child can participate reliably in behavioural testing, those results should be obtained and compared with the earlier objective findings.

The American Academy of Audiology recommends a cross-check approach: behavioural, physiologic and electrophysiologic findings should support one another, and discrepancies should be investigated rather than ignored.

Frequently asked questions

Is ABR painful?

No painful stimulation is required. The electrodes sit on the skin and only record responses. Sounds are presented through earphones or inserts.

Are ABR and КСВП the same test?

In practical clinical use, yes. ABR is the English term—auditory brainstem response. КСВП is the commonly used Russian-language term for short-latency auditory evoked potentials.

Does ABR show the exact degree of hearing loss?

Frequency-specific diagnostic ABR can provide clinically useful estimates of hearing sensitivity, but those estimates require method-specific interpretation and should be cross-checked with the rest of the test battery.

Can ABR be done if OAE is normal?

Yes, when clinically indicated. OAE and ABR assess different parts of the auditory system.

What if my baby does not fall asleep?

Movement increases artefact. Sometimes part of the test can be completed while the child is quietly awake; in other cases the clinician may allow more settling time or reschedule. The decision depends on recording quality and the diagnostic question.

ABR assessment in Almaty

Ekaterina Vladimirovna Kravchenko provides paediatric audiological assessment including ABR and, when indicated, extended objective testing with ASSR.

ABR for Parents: What the Test Shows