Question
When performing an ABR with an infant for the purpose of hearing assessment, I first use a click stimulus. To get frequency-specific information, would you recommend next using chirp stimuli or tone bursts?
Answer
In my opinion, the sequence of stimuli to use for ABR measurement in infants and young children is: 1) click, 2) tone burst (TB), and 3) chirp stimuli to refine auditory threshold.
Maybe someday we will go directly to chirp stimuli at moderate to low intensity levels, bypassing conventional TB stimuli. The problem with that approach is that chirp stimuli lose their effectiveness for intensity levels above about 60 dB nHL. If the click ABR was entirely normal (threshold of 20 dB or better), then you could go to chirp stimulation at less than 60 dB. However, if there was a moderate or severe hearing loss at any frequency by ABR measures, it would still be necessary to use conventional tone bursts or the ASSR to estimate threshold.
For an in-depth discussion of this topic, please view Dr. Hall’s recorded course on AudiologyOnline, Application of ABR in Objective Assessment of Infant Hearing
