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Thomas Lunner

Research Area Manager & Adj. Professor

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mail@eriksholm.com

A method for measuring perceived listening effort of understanding speech in noise was developed. A visual analogue scale was used in a speech recognition test at fixed signal-to-noise ratios in different noise signals.

Method

A method for measuring perceived effort of understanding speech in noise was developed and tested. This method assesses perceived listening effort using a visual analogue scale in different noise types and at fixed signal-to-noise ratios.

In each signal-to-noise ratio, subjects were presented with five sentences, which they were asked to repeat. Having done this, they then rated the effort associated with listening to speech in background noise. The Dantale II corpus was used as speech material, and both unmodulated and modulated, speech-shaped background noise was used.

The reason the subjects were asked to repeat the sentences was to make sure they made an effort to understand the speech being presented. As well as rating perceived effort, they were asked to comment (using short sentences or keywords) on the effort required in each listening situation.

  • Listening Effort Test fig 1

Results

The results revealed that the effort measure shows differences not only between various noise types but also various user groups. Different levels of perceived effort seem to be used by user groups with different cognitive abilities, especially in modulated background noise. The method seems to be appropriate, as the subjects were able to participate and complete their assigned tasks. The effort ratings seem to be both consistent and reliable. Test-retest data shows that there seem to be no training effects, since the differences between repeated ratings are very small.

  • Listening Effort Test fig 2

Further reading

Rudner M, Lunner T, Behrens T, Thorén ES, Rönnberg J (2012). Perceived effort during aided speech recognition is influenced by cognitive capacity. Journal of the American Academy of Audiology.

Rudner M, Rönnberg J, Lunner T (2011). Working memory supports listening in noise for persons with hearing impairment. Journal of the American Academy of Audiology, 22(3), p. 156-167.