The goal of this study is to evaluate the sensitivity of a newly-developed prototype device in its ability to measure brain responses to speech sounds in an infant population. The main research questions are: 1) Is the prototype sensitive to brain response differences from infants with hearing loss with and without hearing aids? and 2) How do the measured brain responses from infants with hearing loss compare to infants with normal hearing who are the same age? Participants will have their brain responses measured using the prototype in response to average-level non-sense speech sounds across 1 to 2 sessions in a "no-hearing aids" condition. Participants with hearing loss who are already fit with hearing aids will additionally undergo a "with hearing aids" recording condition.

In addition to the listed collaborator sites under the "sponsors and collaborators" section, this study is conducted in collaboration with the National Acoustic Laboratories (NAL), Australia, who serve as an international clinical research site contributing to data collection and scientific expertise in pediatric audiology. The prototype is being provided by Audioscan, Dorchester, ON, Canada.

Additionally, the newly developed clinical prototype device is not a U.S. FDA-regulated device. ClinicalTrials.gov registration is being completed as a prerequisite for Health Canada's investigational testing of medical devices, as outlined in Health Canada's 2007 Notice concerning registration and public disclosure of clinical trial information. The application number for Health Canada's investigational testing authorization is 389562.

Inclusion Criteria:

1. Infants (3 to 24 months of age) with normal hearing who have passed their audiological diagnostic evaluation
2. Infants (3 to 24 months of age) identified with hearing loss at their audiological diagnostic evaluation, whose parents have chosen spoken language as their form of communication, and who have been prescribed and fitted with a hearing aid(s).

Exclusion Criteria:

Participants who have abnormal middle ear measure results or occluding ear wax will be excluded.

For the reasons of transparency and education, it is strongly encouraged by many medical journals and other authorities to publish the anonymized data from clinical studies for public use. This data is visible to researchers or the general public after the study is over. Researchers may use this data to improve knowledge about brain responses to speech sounds.

We will publish the following anonymized data from this study: audiogram, middle ear analysis, speech test scores, and auditory evoked potentials. Note that there will be NO personal identifiers in this list.

The de-identified IPD and supporting information will be available beginning immediately after publication, with no end date.

Access to individual participant data will be restricted to authorized research personnel directly involved in data collection, compilation, and analysis at Western University, Dalhousie University, and the National Acoustics Laboratories. Each site will retain identifiable information locally, including consent forms and master lists, which will not be shared. Only de-identified data will be uploaded to a secure, password-protected SharePoint system hosted by Western University for shared analysis. The industry partner (Audioscan) may receive de-identified technical output only if needed for prototype improvement. No identifiable information will be released externally, and results will be reported in aggregate form only.