Research PaperMaturation of middle ear transmission in children

- Children between 5 and 9 years show maturational effects in absorbance.
- Maturation of absorbance occurs in a frequency dependent manner.
- Group delay is mature in children.
- Maturation of middle ear transmission is complete by 10-12 years.

The goal of the current study was to characterize the normative features of wideband acoustic immittance in children for describing the functional maturation of the middle ear in 5 to 12-year-old children. Absorbance and group delay were measured in adults and three groups of children, 5-6, 7-9 and 10-12-year-olds, in a cross-sectional design. Absorbance showed significant effects of the age group in four out of ten center frequencies of one-half-octave bins from 211 to 6000 Hz, while there was no significant effect for group delay at any frequency. Older children (10-12 years) showed absorbance similar to adults. Test-retest reliability was high for absorbance for all age groups. However, group delay was modestly reliable only for adults. We conclude that the middle ear transmission follows a protracted period of maturation for high frequencies and reaches adult-like feature by 10-12 years of age.