Evaluation of the Effect of Frequency-Shifting Technique Used in Hearing Aids for Speech Discrimination

To evaluate the effect of frequency-shifting techniques recently used in hearing aids for speech discrimination scores and hearing thresholds.

Thirty individuals (16 men and 14 women) with sensorineural hearing loss who used normal fitting monaural hearing aids and frequency-shifting feature for at least 2 months and whose 4000-8000 Hz hearing threshold was over 70 dB participated. The average age was 69.73 ± 10 (range: 65-80 years). We detected the types and degree of each participant's hearing loss. Measurements with and without hearing aids were made in a free field. For speech discrimination scores, 6 listings consisting of 25 monosyllables have been used. It has been avoided to learn words thanks to presentation of words in different listings to subjects.

Pure-tone averages of the participants were measured using a supra-aural headphone, normal fitting hearing aid, and frequency-shifting feature. The results were 55.93 ± 6.89, 40.47 ± 5.48, and 36.73 ± 5.72 dB, respectively (p˂0.05). Speech discrimination scores for hearing aids worn on the right ear were measured as 67.73 ± 12.42%, 77.33 ± 10.33%, and 82.13 ± 10.46% with supra-aural headphones, normal fitting hearing aids, and frequency-shifting feature, respectively. Scores for hearing aids worn on the left ear were 68 ± 7.56%, 76.80 ± 6.96%, and 82.13 ± 6.67% with supra-aural headphone, normal fitting hearing aid, and frequency-shifting feature, respectively (p˂0.05).

Elderly individuals using hearing aids had low speech discrimination scores. The frequency-shifting feature recently used in hearing aids significantly increased the scores, making a significant contribution to the solution of speech reception and communication problems in cases of high-frequency hearing loss caused by presbyacusis in elderly individuals..