Ethical Declaration

Institutional Review Board Approval

All procedures conducted in this study were reviewed and approved by the Institutional Review Board (IRB) at Pohang University of Science and Technology (POSTECH). The research protocol was evaluated to ensure compliance with ethical standards for human subject research.

Informed Consent Process

Each participant provided written informed consent after receiving a detailed explanation regarding the purpose of the study, data handling processes, and confidentiality measures. The consent process ensured that all participants were fully aware of:

• The overall research objectives and significance
• The recording procedures and time commitment
• How their data would be processed and stored
• How their recordings would be utilized in research

Privacy and Data Protection

Participants were specifically informed that their voice recordings would be shared publicly in an anonymous format, ensuring privacy and confidentiality. The following measures were implemented to protect participant privacy:

• All personally identifiable information was separated from the recordings
• Participants were assigned anonymous identifiers
• No demographic information that could potentially identify individuals was linked to specific recordings
• All data is distributed in compliance with relevant data protection regulations