Acclimatization effect in speech recognition: evaluation without hearing aids

Area of Science:

• Audiology
• Hearing Science
• Speech Perception

Background:

• Hearing aid adaptation is expected to improve speech understanding through a process called acclimatization.
• Understanding acclimatization's impact is crucial for optimizing hearing aid use and patient outcomes.

Purpose of the Study:

• To evaluate the effect of hearing aid acclimatization on speech recognition thresholds in quiet (SRTQ) and noise (SRTN).
• To assess changes in sentence recognition in new hearing aid users before and after acclimatization, without wearing the devices.

Main Methods:

• Forty participants (28-78 years) with mild-to-moderate sensorineural hearing loss were tested.
• Speech recognition tests were conducted in three sessions: pre-adaptation, 14 days, and 3 months post-adaptation.
• The Portuguese Sentences Lists test was used to obtain SRTQ and SRTN, with noise levels at 65 dB A.

Main Results:

• Mean SRTQ values decreased from 54.43 dB A (session 1) to 51.71 dB A (session 2) and 52.22 dB A (session 3).
• Mean signal-to-noise ratios improved significantly from 1.67 dB A (session 1) to 0.30 dB A (session 2) and -0.03 dB A (session 3).
• Statistically significant differences were found between session 1 and sessions 2/3 for both SRTQ and SRTN.

Conclusions:

• A progressive reduction in sentence recognition thresholds and signal-to-noise ratios was observed.
• Improved performance, even without hearing aids, suggests a genuine acclimatization effect.
• These findings highlight the neuroplastic changes contributing to enhanced speech perception after hearing aid use.