Clinical and pathologic correlates of brain stem auditory response abnormalities.

Short-latency auditory evoked responses were recorded in over 100 neurologic patients. Abnormalities of each response component were correlated with postmortem or radiologic localization of different brain stem lesions. These findings suggested that waves I-VII largely reflect activity at the following levels of the auditory pathway: acoustic nerve (I), pontomedullary junction (II), caudal pons (III), rostral pons or midbrain (IV), midbrain (V), thalamus (VI), and thalamus or auditory radiation (VII). When this information was applied prospectively to the evaluation of brain stem dysfunction, response abnormalities proved useful in detecting and localizing certain lesions not revealed by other tests. Serial recordings provided information about the evolution of brain stem lesions and their response to therapy.