Audiogram

For adults, a behavioural hearing test involves a tester who presents tones at specific frequencies (pitches) and intensities (loudnesses).

With children, an audiologist makes a game out of the hearing test by replacing the feedback device with activity-related toys such as blocks or pegs.

[4] Audiograms are produced using a piece of test equipment called an audiometer, and this allows different frequencies to be presented to the subject, usually over calibrated headphones, at any specified level.

The levels are, however, not absolute, but weighted with frequency relative to a standard graph known as the minimum audibility curve which is intended to represent a 'normal' hearing.

"Conventional" pure tone audiometry (testing frequencies up to 8 kHz) is the basic measure of hearing status.

[6] For research purposes, or early diagnosis of age-related hearing loss, ultra-high frequency audiograms (up to 20 kHz), requiring special audiometer calibration and headphones, can be measured.

[14] Audiograms are unable to measure hidden hearing loss,[15][16] which is the inability to distinguish between sounds in loud environments such as restaurants.

Audiograms are designed to "estimate the softest sounds the patient can detect", and are not reflective of the loud situations that cause difficulties for people with hidden hearing loss.

Audiograms may not reflect losses of nerve fibers that respond to loud sounds, key to understanding speech in noisy environments.

Audiogram
Results of a hearing test plotted on an audiogram illustrating a typical "noise notch" in the left ear
Audiogram showing a typical "noise notch" in the left ear (normal hearing in the right ear)