Area-Under-the-Curve Measure of the Auditory Middle Latency Response (AMLR) From Birth to Early Adulthood

The area-under-the-curve (AUC) measure of the auditory middle latency response (AMLR) waveform was derived and analyzed from recordings in 50 subjects with normal hearing. The AUC metric is believed to represent the total amount of neural energy contributing to the evoked response. This proposed method of measure, therefore, may provide an alternative method of quantifying the response. The subjects were divided into five age groups (n = 10 for each group): infants, children, preteens, teens, and adults. Ipsilateral and contralateral recordings of the AMLR were obtained at two stimulus levels (70 and 40 dB nHL) and at two stimulus rates (11.3 and 3.3/s). AUC measures were obtained for each recording at 70 and 40 dB nHL and at 3.3 and 11.3 clicks/s. These area measurements were compared among the five age groups for significant differences due to age. According to the results, no significant differences in the AUC of the AMLR waveform existed as a function of age.