Significantly improves understanding and listening effort in noise

HeardThat is a smartphone app that aims to help people understand conversations better in noisy environments. The app uses artificial intelligence to remove background noise and deliver enhanced speech to the user’s listening device such as earbuds or hearing aids.

Singular Hearing, the developers of HeardThat, conducted a study to evaluate if the app actually improves speech understanding and listening effort compared to noisy conditions without the app.

Testing with real-world audio

Twelve adult participants who reported having difficulty hearing conversations in noise listened to sentences recorded in three conditions: a quiet room, a noisy café, and a noisy café with HeardThat processing. They repeated back what they heard and word and sentence errors were measured. Participants also rated listening effort.

The results

Every single participant made fewer word and sentence errors with HeardThat compared to the noisy environment. On average, HeardThat reduced word errors by 76% and sentence errors by 85% compared to the noisy environment without HeardThat.

All participants also reported lower listening effort using HeardThat, with the average effort level close to that for quiet conditions.

Impact of the results

Word and sentence understanding

The images below visualize the improvement that HeardThat provides. These are not the actual sentences, but convey how many words or sentences were misunderstood. The red highlights show the percentage of errors in understanding before HeardThat (left) and after (right) for words (Figure 1) and for sentences (Figure 2).

Figure 1. Reduction in word errors. Red highlights show the proportion of misunderstood words before and after HeardThat processing.

Figure 2. Reduction in sentence errors. Red highlights show the proportion of misunderstood sentences before and after HeardThat processing.

Listening effort

Shari Eberts has compared hearing loss to playing Wheel of Fortune where “Some of the letters are filled in; others are blank.” The listener has to fill in the gaps in what they understand, which “takes a lot of brain power and can be exhausting.” The images above convey why listening effort is reduced—there are fewer gaps to fill in.

Conclusions

In summary, these controlled tests found that HeardThat significantly increases speech understanding and reduces effort for listening in noise. These quantitative results are consistent with what we have observed in numerous demonstrations and with the reports from those using HeardThat in their daily lives.

A more detailed report on the study can be found here.