Bandpass filter settings differentially affect measurement of P50 sensory gating in children and adults

Objective: This study investigated the effect of four different bandpass filter settings on measures of the P50 component and the signal-to-noise ratios (SNR) of averaged ERPs obtained from a sensory gating paradigm employing paired-click stimuli. Methods: Participants were adults (n = 18) 20-55 years old and children (n = 25) 5-10 years old who were free of neurological disorders. Results: Results show that the filter settings (0.23-75 Hz, 10-50 Hz, 10-75 Hz, and 10-200 Hz) differentially affected the P50 amplitude, noise power and SNR measures of the conditioning and test clicks, and P50 T/C ratios. Conclusions: The 10-50 Hz filter setting may be optimal in studies that include only adults as these settings resulted in the smallest mean P50 T/C ratio, a reasonable standard deviation (SD) for the ratio, and the highest SNRs. The 10-200 Hz filter may be the best for studying young children as this setting had the smallest mean and SD of P50 T/C ratios for these participants. Significance: In studies that include both adults and children investigators are advised to use the 10-200 Hz filter setting because the smaller variability of sensory gating in the child group helps ensure better homogeneity of variance measures between the groups. (C) 2012 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.