What does a tympanogram depict?

• A. A graphic picture of middle ear function as the pressure is varied
• B. The acoustic reflex threshold
• C. The cochlear baseline
• D. The neural conduction speed

Answer: (A)

A tympanogram is a readout of how the middle ear responds when air pressure in the ear canal is changed. It graphs the tympanic membrane’s mobility (compliance) as the pressure varies, showing how easily the eardrum moves at different pressures. The resulting curve helps reveal middle-ear status—normal mobility, negative pressure, fluid, perforation, or other dysfunction—by showing the pressure at which the system is most compliant. In short, it’s a graphic picture of middle ear function as pressure is varied. The other options point to different parts of the auditory system (acoustic reflex thresholds, cochlear status, neural conduction) and do not describe what a tympanogram depicts.