Central slowing of auditory brainstem responses (ABRs) and excessive breathing irregularity on pneumogram recordings indicate dysfunction in central auditory pathways and brainstem respiratory control mechanisms, respectively. These centers are anatomically proximate within the brainstem so that ABR slowing and respiratory instability might be expected to occur concomitantly, reflecting overall dysfunction of this part of the central nervous system. To examine the relationship between these two assessments, testing results were compared for 15 infants in the intensive care nursery who had ABRs and 12-hour pneumograms performed at about the same age for separate clinical indications. Wave V latency at 70 dB was found to correlate significantly with three pneumogram measurements of breathing irregularity: the density of short apneas during sleep (p less than 0.01), the number of episodes of periodic breathing per 100 minutes of sleep (p less than 0.05), and the percentage of sleep time spent in periodic breathing (p less than 0.05). Interwave interval I-V correlated significantly with the density of short apneas during sleep (p less than 0.01). The auditory brainstem response and the pneumogram appeared to serve as related indicators of brainstem function in these infants.