A Dual-Function Evoked-Potential Stimulus for Assessing Audibility and Functional Hearing

Background: The auditory brainstem response (ABR) is the gold standard for pediatric screening, but it captures threshold information only. Speech-evoked frequency-following responses (FFRs) index sustained, periodic speech encoding yet are rarely added in busy clinics. A single stimulus that elicits both would improve efficiency and broaden functional assessment. Purpose: We tested whether a combined stimulus yields ABR peaks and FFR magnitudes equivalent to those obtained with conventional, separate protocols. Research Design: This was a within-subject, three-condition comparison: click ABR (80, 60 dB), conventional speech-evoked FFR (cABR), and ABR+ (60-dB click followed by a short steady vowel). Study Sample: Twenty-three children without hearing difficulties (3–12 years of age; mean 6.65 years) were recruited during routine electrophysiology at Nanjing Maternity and Child Health Care Hospital. Data Collection and Analysis: Recordings used a standard vertical montage with epoch windows of −10 to 12.5 ms for click ABR and −20 to 55 ms for cABR and ABR+. For ABR outcomes, three blinded raters marked waves I, III, and V on individual averages. For FFR outcomes, root mean square and narrow-band fast Fourier transform magnitudes (100, 200, 300, and 400 Hz; ±30 Hz) were computed on a fixed vowel window with prestimulus noise subtraction. Repeated-measures models tested condition effects (and frequency for FFR); paired t tests used Holm correction and effect sizes were reported as Cohen’s d. Results: ABR latency analyses showed the expected level effects (80 dB < 60 dB) for waves I, III, and V. Critically, wave V latency did not differ between the 60-dB click ABR and the ABR+ click segment. In the frequency domain, spectra declined from 100 to 400 Hz with no main effect of condition and no condition × frequency interaction. Conclusions: ABR+ reproduces click-ABR timing and speech-FFR magnitudes obtained with separate protocols, consolidating threshold-relevant synchrony and suprathreshold speech encoding in a single, clinic-feasible run. Clinical Relevance Statement: ABR+ can streamline pediatric assessments by providing a measure of audibility and functionally relevant encoding of periodic speech in one recording. This supports broader, time-efficient adoption of speech-evoked brainstem measures in clinical workflows.