Basic NeuroscienceTowards an optimal paradigm for simultaneously recording cortical and brainstem auditory evoked potentials

- Present a new stimulus paradigm for concurrent recording of brainstem/cortical ERPs.
- Clustered/variable stimulus presentation was optimized to reduce habituation.
- ERP morphologies and response amplitudes were similar to conventional paradigms.
- The new optimal paradigm offers a 3-fold increase in recording efficiency.
- Offers rapid collection of multiple auditory ERPs in research/clinical settings.

BackgroundSimultaneous recording of brainstem and cortical event-related brain potentials (ERPs) may offer a valuable tool for understanding the early neural transcription of behaviorally relevant sounds and the hierarchy of signal processing operating at multiple levels of the auditory system. To date, dual recordings have been challenged by technological and physiological limitations including different optimal parameters necessary to elicit each class of ERP (e.g., differential adaptation/habitation effects and number of trials to obtain adequate response signal-to-noise ratio).New methodWe investigated a new stimulus paradigm for concurrent recording of the auditory brainstem frequency-following response (FFR) and cortical ERPs. The paradigm is “optimal” in that it uses a clustered stimulus presentation and variable interstimulus interval (ISI) to (i) achieve the most ideal acquisition parameters for eliciting subcortical and cortical responses, (ii) obtain an adequate number of trials to detect each class of response, and (iii) minimize neural adaptation/habituation effects.Results and comparison with existing methodComparison between clustered and traditional (fixed, slow ISI) stimulus paradigms revealed minimal change in amplitude or latencies of either the brainstem FFR or cortical ERP. The clustered paradigm offered over a 3× increase in recording efficiency compared to conventional (fixed ISI presentation) and thus, a more rapid protocol for obtaining dual brainstem-cortical recordings in individual listeners.ConclusionsWe infer that faster recording of subcortical and cortical potentials might allow more complete and sensitive testing of neurophysiological function and aid in the differential assessment of auditory function.