The importance of acoustic reflex for communication

The purpose of the study was to compare the speech recognition capacity between listeners with and without acoustic reflex using different types of noises and intensities.

We studied 18 women allocated to 2 groups: acoustic reflex present (20 ears) and absent (16 ears). They were presented with 180 disyllable words (90 to each ear), emitted randomly at a fixed intensity of 40 dB above the pure tone average hearing level. At the same time, 3 types of noises were presented ipsilaterally (white, pink, and speech), one at a time, at 3 intensities: 40, 50, and 60 dB above the pure tone average hearing level.

The ages and auditory thresholds were statistically equal between the groups. There was a significant difference in mean number of hits between the 2 groups for the 3 types of noises used. There was also a significant difference in mean number of hits for noise type and intensity when white and pink noise was used at 40 and 50 dB and for all the intensities when speech was used.

Acoustic reflex helps communication in high-noise environments and is more efficient for speech sounds.