Effects of impeded breathing on auditory brainstem responses in conscious man

Auditory brainstem responses (ABR) recorded in two groups of 10 normal volunteers were compared under conditions of impeded and unimpeded breathing. Impedance to breathing was accomplished by adding inspiratory flow-resistive loads of varying magnitude. Loaded breathing selectively augmented the amplitude of ABR components generated in the vicinity of the ponto-midbrain junction. Peak latencies and other peak amplitudes of the ABR were unaffected. These findings suggest that the ABR procedure may serve as a direct noninvasive approach to the assessment of brainstem respiratory functions in conscious humans.