THE EFFECT OF STIMULUS REPETITION RATE ON THE DIAGNOSTIC EFFICACY OF THE AUDITORY-NERVE BRAIN-STEM EVOKED-RESPONSE

This study investigates the hypothesis that an increase in the click presentation rate during diagnostic testing with the auditory nerve-brain-stem response (ABR) will increase the efficiency with which lesions may be detected in the nervous system. Cats were exposed to conditions of hypoxia, hypercapnia and acidemia, and hypoglycemia was induced in rats. ABR was recorded using the standard 10/sec click rate and also a higher (55/sec) rate during both the control state and the experimental state. Various parameters of the ABR were compared at the two click rates in the control and experimental states to see if the higher click rate was more effective in detecting pathology in the nervous system. It was found that in only a very few cases was the higher stimulus presentation rate more effective, and that in general ABR recordings at one stimulus rate only is quite sufficient for work in a clinical setting.