Inexpensive Brainwave Authentication: New Techniques and Insights on User Acceptance

Brainwaves have proved to be unique enough across individuals to be useful as biometrics. They also provide promising advantages over traditional means of authentication, such as resistance to external observability, revocability, and intrinsic liveness detection. However, most of the research so far has been conducted with expensive, bulky, medical-grade helmets, which offer limited applicability for everyday usage. With the aim to bring brainwave authentication and its benefits closer to real world deployment, we investigate brain biometrics with consumer devices. We conduct a comprehensive experiment that compares five authentication tasks on a user sample up to 10 times larger than those from previous studies, introducing three novel techniques based on cognitive semantic processing. We analyze both the performance and usability of the different options and use this evidence to elicit design and research recommendations. Our results show that it is possible to achieve Equal Error Rates of 14.5% (a reduction between 37%-44% with respect to existing approaches) based on brain responses to images with current inexpensive technology. With regard to adoption, users call for simpler devices, faster authentication, and better privacy.