Effects of electrode montage on the spectral composition of the infant auditory brainstem response.

We evaluated the effect of electrode montage on the spectrum of the infant auditory brainstem response (ABR). Spectral profiles of ipsilateral, contralateral, noncephalic, and horizontal recordings obtained in response to slow and fast repetition rates and at low and high stimulus intensities were also evaluated. Findings indicate that the spectrum of the infant ABR is dominated by low-frequency energy, maximal below 200 Hz. The spectra of ipsilateral and noncephalic recordings are the strongest irrespective of stimulus intensity or repetition rate. Increase in stimulus intensity or repetition rate typically enhances the amount of energy below 200 Hz. These results reinforce the clinical utility of ipsilateral and noncephalic recordings for screening, threshold measurement, and neurodiagnostic purposes.