A real-time recording system for brainstem auditory evoked responses and the study of stimulus polarity effects

A real time recording system for the brainstem auditory evoked response (BAER), is designed, developed and evaluated by testing the known effects of click polarity on interpeak latencies (IPLs) of the BAER in normals and in patients with suspected brainstem ischaemia. The click polarity is found to affect IPLs. The rarefaction click is found to generate the clearest waveform and it would be the most useful in clinical diagnosis.