Effects of rate (0.3-40/s) on simultaneously recorded auditory brainstem, middle and late responses using deconvolution

Abstract

Objective: Auditory evoked potentials (AEPs) are typically acquired in either transient (low-rate) or steady state (high-rate) conditions. This study utilizes deconvolution to obtain transient responses over a range of rates from 0.3 to 40/s, to establish a rate profile of transient responses employing uniform recording conditions.

Methods: Deconvolution is used to obtain transient responses from quasi steady state recordings for rates 3.5-40/s, and components are scored and waveform morphologies are compared across rates.

Results: All component latencies remain stable across all rates other than P2, which decreases for rates up to 3.5/s. Amplitudes for brainstem (V, Na), middle latency (Pa, Nb), and late (Pb/P1, N1 and P2) responses increased for rates below 1, 2 and 3.5/s, respectively. Rates between 3.5 and 25/s undergo a gradual morphology transition, above which oscillations begin to occur after 100 ms.

Conclusions: Auditory brainstem, middle and late latency components other than P2 show stable latencies across 0.3-40/s with varying amplitude rate dependencies.

Significance: Obtaining a transient response rate profile utilizing uniform acquisition parameters is useful for an improved understanding of how individual AEP components interact with stimulation rate, and can provide a more comprehensive assessment of the ascending auditory pathway and primary auditory cortices.

Keywords: Adaptation; Auditory evoked potentials; Chirp; Deconvolution; Rate effects; Transient response.