In auditory brainstem response (ABR) testing, Wave V originates from which neural structure?
- A Cochlear nerve (VIII cranial nerve)
- B Inferior colliculus (midbrain) ✓
- C Cochlear nucleus in the pontomedullary junction
- D Superior olivary complex (pons)
Correct answer: B. Inferior colliculus (midbrain)
Explanation
In ABR, the five waves represent sequential neural generators: Wave I — distal cochlear nerve; Wave II — proximal cochlear nerve/cochlear nucleus; Wave III — cochlear nucleus/superior olivary complex junction; Wave IV — lateral lemniscus; Wave V — inferior colliculus (midbrain). Wave V is the most robust and clinically important wave, used for threshold estimation and monitoring in intraoperative settings. Its latency and interpeak latencies (I-III, III-V, I-V) are used to localize retrocochlear pathology.
Reference: Dhingra Diseases of Ear, Nose and Throat, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.