This study aims to explore if objective brain responses to speech stimuli (words and running speech) can be used to evaluate hearing aid fitting in adults. Objective brain responses would be beneficial, as they could be used to evaluate hearing with people who are incapable or unwilling to provide subjective responses. The study aims to determine if EEG responses to speech sounds are sensitive to the effects of hearing aids for hearing aid users. Secondary, the study will look into the need for using speech stimuli in order to obtain more robust responses compared to current clinical standards.

The research questions addressed are as follows

1. Are speech-evoked objective brain responses sensitive to hearing aid amplification?
2. Are speech-evoked brain responses sensitive to distortions in speech and can hearing aid amplification resolve issues with brain responses to distorted speech?
3. Which tests are optimal for detection of objective brain responses to speech?
4. Are realistic speech stimuli (words or running speech) able to robustly detect brain responses compared to current clinical standards (clicks and tones)? The study will be carried out on a group of mildly to moderately hearing impaired subjects between the age of 18 and 70. Subjects will be recruited from the Royal Berkshire NHS Foundation Trust, where the research will be conducted. Participants will have their hearing function and hearing aid fitting checked as described in the design and methodology section of this proposal. During the experiment, participants will be asked to listen to speech sounds presented from a loudspeaker at comfortable listening levels. The responses will be measured with the participant wearing and not wearing hearing aids. Additionally, participants will perform a behavioural task for perception of speech. Participants will be asked to attend 2 sessions of 2 hours. Data collection will run over 1 year.

Inclusion Criteria:

• Subjects are between 18 and 70 years old
• Native English speakers
• Have mild to moderate hearing loss in their better ear measured using current clinical standards
• Routine hearing aid users

Exclusion Criteria:

• Clinical observation indicates the presence of ear infections or an occluded ear canal on the day of testing
• Subjects with recent ear surgery (within a month before the day of testing)
• Subjects who are taking substances that could affect brain responses (e.g. medication for the treatment of depression)

Subjects will be included if they are between 18 and 70 years old, are native English speakers and have mild to moderate hearing loss in their better ear measured using current clinical standards. They will be identified from their medical records of the Royal Berkshire NHS Foundation Trust by the Co-Investigators who are trained and qualified clinical audiologists at the Trust. Subjects will be routine hearing aid users.

Anonymised data will be collected and stored in Pure/ePrints at the University of Southampton along with a metadata file describing the procedure and providing participant demographics such as age and gender. Anonymised data will also be stored on password-protected University computers and backed up on password-protected hard drives. Anonymised data will be kept available for public access (for research and teaching purposes) under guidelines of the University of Southampton for at least 10 years. Clear information regarding the storage and possible reuse of anonymized data will be given to the participant prior to the experiment. Participants will have the possibility to opt out of this data sharing policy.