 It is well known that there is a segment of the population with normal audiograms who struggle communicating in noisy places such as cafeterias or noisy restaurants, and that of biologists and clinicians lack of standardized guidelines on how to optimally treat these patients. I am Joaquin Malerama, a senior research scientist at the National Acoustic Laboratories in Sydney, Australia, and today I will talk about the perceived value of the Apple AirPods Pro as an assistive listening device by people who do not have hearing loss but present important hearing-in-noise difficulties. Following a conversation when there is noise around is a complex task that our brain and our auditory neural structures can accomplish. However, this task becomes more difficult when we start to experience early signs of hearing loss, even before the audiogram shows that there is a problem. This figure here is from Humes 2021 that was published in hearing and estimates the prevalence of people with reported hearing difficulties which was evaluated via a validated short questionnaire for screening the hearing handicap inventory for the elderly in terms of their pure tone audiogram measured via the four frequency average hearing loss in the better year. As we would expect, this figure shows that people with greater hearing loss report more important hearing difficulties and we also know that for those with hearing loss, hearing aids and cochlear implants and other technologies have been proven to be effective to compensate for their hearing loss. However, there is a segment of the population who are reporting important hearing difficulties but because they do not have hearing loss, they do not receive any help and the hearing difficulties of this segment of the population should not be taken without importance for several reasons. First, they do have a negative impact on the quality of life experiencing them who usually report to reduce their social encounters and experience, anxiety, all of which are risk factors for developing dementia eventually. Second, this problem also affects clinicians who report to feel frustrated and disoriented when they don't know what to recommend to these patients. And also, this problem is of a very high magnitude because it affects the whole population as these hearing difficulties commence as we all age and they are accelerated if we have a history of noise exposure. Very similar to sun exposure accelerating skin aging, for example. All of this points out the importance of developing a standardized guidelines for managing people with early signs of hearing loss and the study that I'm presenting today attains this need and evaluates the value of the Apple AirPods Pro as an assistive listening device for people with hearing difficulties but with audiometric thresholds within the so-called normal limit. So this study takes advantage of three novel features that were released with IOS 15 which enable the AirPods Pro to be used as assistive listening devices. So these features are headphone accommodations which provides gain to sounds delivered by the AirPods aimed at compensating for hearing loss, conversation boost which uses directionality to enhance the quality of the sounds coming from the front, and ambient noise reduction which uses advanced signal processing algorithms to attenuate the effect of background noise. So these features combine, they are expected to improve communication in noisy environments and I also wanted to say that if you're interested in learning more about how to set up these novel features in your iPhone, I recommend that you watch the soundbites presentation of my colleague Nicky Chong and you can find this webinar in YouTube or scan the QR code there in the screen. So for this study we recruited 17 participants aged between 21 and 59 years and nine of them being female. So for each participant what we did was to personalize the fitting of the AirPods Pro by inserting their built-on audiogram, setting ambient noise reduction to the max level and enabling a conversation boost. And we measured the value of the AirPods Pro as assistive listening devices from different angles. So first we did acoustic measures in the lab to characterize the performance of the devices. Then we estimated the hearing benefit of the devices via a standardized speech and noise test in the lab and interestingly we also asked participants to try out the devices in real situations where they struggle communicating with their peers such as noisy restaurants and cafes. Anyway at the end of the study we also asked them a few questions to learn more about their experience. So let's see the results. So acoustic measures aim to measure the benefits that the AirPods Pro provide and for this a person wearing the AirPods Pro was seated in the center of an array of 16 speakers as we can see here in the picture. So the AirPods Pro were configured with the average audiogram across participants and we can see in that in that figure that it's a normal hearing profile very symmetrical between the two ears. Then we used the proto microphones in the ear canal to take real ear measurements and we presented multi-talker noise from all the speakers at 65 dB SPL. The target speech consisted of short sentences presented from the front speaker at 61.5 dB SPL which corresponds with an SNR of minus 3.5 dB which is very typical one that we can usually find in noisy restaurants. And then we estimated the speech intelligibility index signal to noise radio advantage via the inversion technique, an index that is associated with the acoustic benefit in frequencies relevant for communication. Well, the results showed that the acoustic benefit provided by conversation boost alone was around 3.2 dB. The benefit, the isolated benefit of ambient noise reduction was about 1.85 dB and the combined effect of both conversation boost and ambient noise reduction was about 5.36 dB which interestingly is comparable with the benefit that we would expect from a hearing aid which is normally in the range between 3 and 6 dB. We used the same experimental setup to investigate if the AirPods Pro actually helped participants hear better in noise. And for this we did, we used the best test that evaluates intelligibility of short sentences presented in noise and this test was administered in a signal to noise radio that corresponded to around 50% intelligibility. Then we ran this test with the participants wearing and not wearing the AirPods Pro. Results show that on average participants wearing the AirPods Pro increase intelligibility in around 11% relative to not wearing them. Also in the same test we asked participants about their self-perceived effort doing that task and they reported that with AirPods Pro they thought that the task was less mentally demanding, that they performed better in the task and that the task required less mental effort, being these differences statistically significant. Well, in addition to laboratory measures we were interested in learning about the participants' hearing experience in real-life situations. And for this we asked participants to attend acoustically challenging places where they have hearing difficulties such as noisy cafeterias or restaurants and we asked them to spend around 50 minutes without the AirPods Pro so they experienced their expected hearing difficulties and then wear the AirPods Pro for around 30 minutes until they gain an understanding of their hearing experience with the devices. Then we asked them to, they were asked to respond to a short survey which was administered via the NIMA app. NIMA is the NAL Ecologically Momentary Assessment and this is a very powerful research tool that allows us to measure different dimensions of their hearing experience including an overall score of the benefit of the AirPods Pro, how much they could understand more with the AirPods Pro, whether they participated in more in conversations, we wanted to learn about their emotional state, to learn if they would continue using the AirPods Pro in similar situations in the future, what were the most relevant barriers that would discourage them to continue using the AirPods Pro in the future and also, interestingly, the microphones could also measure how noisy was the place. So on average, participants did around 10 participants each, 10 surveys each, and leading to a total database of 174 surveys. Most of the surveys were taken in cafes, restaurants, parties at home and shopping centers and we also see that 74 surveys were on one-on-one conversations, 77 in a group of three people and 23 in a group of more than six people. This figure also shows that the distribution of the background noise level of the events that the participants attended and this shows that participants indeed attended noisy places as most of the surveys were taken in sound environments between 70 and 90 DBA. When participants were asked to compare their hearing experience with and without the AirPods Pro, about half of them reported to be about the same and five of them said that it was a bit better with the AirPods Pro, four of them said to be significantly better. So on a scale 1 to 5, the average score was 3.6, which fits into the category of a bit better with the AirPods Pro. So consistent with this outcome, participants reported that with AirPods Pro, they were able to understand a bit better and also to participate a bit more in conversations. Participants were also asked about their emotional state and here we see some variability with three participants feeling a bit more frustrated and other feeling more confident. The majority reported to feel about the same with and without the AirPods Pro. Similarly, we observed variability when participants were asked about whether they would continue using the AirPods Pro in similar situations in the future. Five participants reported to be either likely or very likely. Other five said that it would be unlikely and the remaining seven weren't sure. Importantly, we found that the most relevant barriers that would discourage participants to keep using the AirPods Pro as assistive listening devices were that their hearing benefit was limited. Some of them reported comfort issues and others reported to feel embarrassed wearing them. Also, at the end of the study, we evaluated their degree of satisfaction with AirPods Pro using the saddle questionnaire, which is a validated questionnaire for hearing aids that we adapted for use with the AirPods Pro. So these questionnaires measure different dimensions of satisfaction, including positives, negatives, services and cost and personal image. Results showed an important spread of satisfaction with seven participants being relatively satisfied in the range of medium considerably or greatly and 10 participants rating lower satisfaction. On a scale one to seven, the average score was 3.34, which corresponds to participants being somewhat satisfied, but we have also to take into account this person. It is also noteworthy that this overall score is lower than the expected level of satisfaction reported by hearing aid users, which is obtained from normative data collected on 365 hearing aid users. We also asked participants to watch the degree do the AirPods Pro improve their hearing experience in noisy places? Seven participants out of 17, which corresponds to 41%, said that not much. For example, one participant said there is some improvement, but it is minimal. When it is windy, for example, in an outside event, the AirPods Pro actually makes the wind noisier and negatively impact your conversations. Another seven from the 17 participants said that it depending on the ambient sound. For example, one of them reported my experience was inconsistent. In one-on-one situations, they performed better compared to group gatherings. In other occasions, sounds like the rubbing of my hair against the AirPods Pro and the sound of my shewing were amplified, whereas other background sounds were not. And the remaining three reported to have a positive experience. One of them said I could hear voices much more clearly in close proximity as well as some distance away. I felt more engaged in conversations because I could hear better. The ability to hear people at the dinner table at a noisy restaurant is probably the most beneficial. We also asked to identify what were the most relevant positives and negatives of the of the AirPods Pro. Amongst the positives, people highlighted that they had a long battery life, that this design was beautiful, they found them small and obtrusive. Some of them reported to be comfortable to wear, to be easy to pair with the iPhone, also to be inexpensive and to be multi-purpose, because you can answer call with them and everything. Amongst the negatives, they said that the hearing and noise benefit that they provided was limited. They also highlighted that they provided a natural amplification of background and wind noises. They also said that they could hear their own voice, so walking or chewing due to their occlusion. Some of them reported to be uncomfortable for a long time use. And some others reported societal and stigma issues because they said that the AirPods Pro are not perceived by others as assistive listening devices. So for example, one participant said, I did not feel at all embarrassed wearing them, but a few people asked me about them and why I was wearing them. In the trial, it was easy to explain the scientific nature of the trial, but this might become irritating if long-term use. It was potentially perceived by others that you were listening to music or doing other things within a group or conversation. Also, I don't think their hearing correction works so well outside in a loudish area on a beach with plenty of ambient environmental noise. We also asked them if they would continue using the AirPods Pro in similar situations in the future. To this question, five of them, which corresponds to about 30% of our participants, said that yes. So one of them said, I would continue using AirPods Pro with family and friends in a group environment and our workmates and associates in a work environment who know the purpose of the AirPods Pro. Again, explaining the purpose of the AirPods would be problematic for me in most of their environments with people I'm not directly associated with. And the remaining 12, which is about 70%, said that no. And the main reasons were the ones that were highlighted earlier, so limited hearing benefits, comfort, and societal stigma. So one of them said, I would not use them in conversations. People think that you are ignoring them if they see you using them and the impact on the quality of the conversation is not significant. Well, to wrap up, probably the take home messages that we can take from this presentation is that laboratory measures show that the AirPods Pro provide an acoustic benefit of around 5 dB, and that AirPods Pro increase intelligibility and reduce self-perceived mental effort in the participants. Real-life measures show that despite the AirPods Pro providing a slightly better acoustic experience, most participants who are 70% would not continue using AirPods Pro in noisy places due to three important barriers. Not enough hearing benefit, discomfort, and stigma as the AirPods Pro are not generally seen as assistive listening devices. So taking together results indicate that AirPods Pro have potential to help a segment of the population with normal audio grants, but the speech and noise hearing difficulties. Also, the barriers identified in this study shall inspire the development of new solutions aimed at increasing the uptake of novel assistive listening devices. And I also wanted to acknowledge the contribution of my colleagues and thank the sponsorship of this research to the Department of Health, Industry and Governments, and thank you all for your attention.