Related Experiment Video
Updated: Jun 27, 2026

Behavioral Assessment of Hearing in 2 to 4 Year-old Children: A Two-interval, Observer-based Procedure Using Conditioned Play-based Responses
Published on: January 23, 2017
Effects of maturation on tympanometric wideband acoustic transfer functions in human infants
Chris A Sanford1, M Patrick Feeney
1Department of Speech and Hearing Sciences, University of Washington, Seattle, Washington 98105, USA.
Abstract:
Wideband acoustic transfer function (ATF) measurements of energy reflectance (ER) and admittance magnitude (|Y|) were obtained at varying static ear-canal pressures in 4-, 12-, and 27-week-old infants and young adults. Developmental changes in wideband ATF measurements varied as a function of frequency. For frequencies from 0.25 to 0.75 kHz there was as much as a 30% change in mean ER and mid |Y| with changes in static ear-canal pressure between 4 and 24 weeks of age. From 0.75 to 2 kHz, the effects of pressure produced a small number of significant differences in ER and mid |Y| with age, suggestive of a developmentally stable frequency range. Between 2 and 6 kHz, there were differential effects of pressure for the youngest infants; negative pressures caused increased ER and mid |Y| and positive pressures caused decreased ER and mid |Y|; the magnitude of this effect decreased with age. Findings from this study demonstrate developmental differences in wideband tympanometric ATF measurements in 4-, 12- and 24-week-old infants and provide additional insight on the effects of static ear-canal pressure in the young infant's ear. The maturational effects shown in the experimental data are discussed in light of known age-related anatomical changes in the developing outer and middle ear.
Related Concept Videos
The Cochlea
Perception of Sound Waves
The pitch of a sound depends on the frequency and the pressure amplitude of the source. Two sounds of the same frequency...
Hearing
Assessing Body Temperature - Tympanic membrane
Step 1: Begin by practicing good hand hygiene to prevent the transmission of microorganisms.
Step 2: Turn on the thermometer and wait until the ready sign appears on the screen to ensure accurate measurement.
Step 3: Slide the probe cover in place to prevent cross-contamination.
Step 4: Instruct the patient to tilt their head to the side for comfort and check for cerumen...
Anatomy of the Ear
Auditory Pathway
When viewed cross-sectionally, the cochlea reveals the scala vestibuli and scala tympani flanking the...
