Machine Learning Based Listener Classification and Authentication Using Frequency Following Responses to English Vowels for Biometric Applications

Abstract

Auditory Evoked Potentials (AEPs) have recently gained attention as a biometric feature that may improve security and address reliability shortfalls of other commonly-used biometric features.The objective of this thesis is to investigate the accuracy with which subjects can be automatically identified or authenticated with machine learning (ML) techniques using a type of AEP known as the speech-evoked frequency following response (FFR).Accordingly, the results show more accurate discrimination between FFRs from different subjects than what has been reported in past studies. The accuracy improvement is searched either by optimized hyperparameter tuning of the ML model or extracting new features from FFRs and feeding them as inputs to the model. Finally, the accuracy of authenticating subjects using FFRs is investigated using a "sheep vs. wolves" scenario.The results of this work shed more light on the potential of use of speech-evoked FFRs in biometric identification and authentication systems.Deciding to pursue a second M.Sc. program after completing my PhD was a turning point in my life and professional career, which I will always remember. Moving forward on this path was impossible without the support and help of my supervisors. Therefore, I would like to express my sincere gratitude to Dr. Martin Bouchard and Dr. Hilmi Dajani for giving me this opportunity and guiding my research. Their fantastic guidance and cooperation throughout my M.Sc. studies were invaluable.Once again, similar to my previous Ph.D., M.Sc., and B.A.Sc. theses, I would like to express my heartfelt thanks to my best friend forever, Mohammad Alavirad, whom I cannot call anything but my brother. His help, presence, and dedication during the last ten years of my life cannot be expressed in words. Without him, it would have been impossible to overcome the challenges and complete this long journey.My parents have played an essential role in helping me achieve our dreams. I am blessed to have parents who have supported and encouraged me during the lowest of lows and the highest of highs, fueling my every moment.