Summary: | The purpose of this paper was to evaluate the possible benefit of hearing aids for reducing listening effort in quiet and in noise. An additional purpose was to investigate the possible relationship between the magnitude of listening effort benefit and individual listeners working memory capacity or lipreading skill. Thirty-six participants with bilateral sensorineural hearing loss were fitted with linear behind-the-ear hearing aids and tested using a dual-task paradigm. The primary task was monosyllable word recognition and the secondary task was a visual reaction time task. In addition, participants rated their perceived effort after each condition. The test conditions varied by hearing aids (unaided, aided), visual cues (auditory-only, auditory-visual), and background noise (present, absent). For all participants, the signal-to-noise ratio was set individually so that speech recognition performance in noise was approximately 50% in both the auditory-only and auditory-visual conditions. In addition to measures of listening effort, lipreading ability and working memory capacity were measured. In general, the effects measured using the objective measure of listening effort were small. The results of this study suggest that, on the average, hearing aids improve objective listening effort; however, this only occurs after a period of acclimatization. Also, people who are not good lipreaders may derive hearing aid benefit when using auditory-visual stimuli, generally because people who are good lipreaders expend less listening effort. Therefore, it is speculated that the addition of the hearing aid provides little, if any, additional benefit. Good lipreaders were also more likely to derive benefit from the presence of visual cues than people who are not good at lipreading. Background noise increased objective listening effort, but neither working memory capacity nor lipreading ability predicted susceptibility to noise. Finally, it should be noted that the magnitude of listening effort was generally small in this study, potentially obscuring the effects of the predictive variables. Further investigation is needed to determine if other methods, which might include more complex secondary tasks, result in greater measured listening effort effects.
|