Events

Abstract

It is increasingly difficult to know who—or what—we are interacting with online. Traditional authentication methods prove credentials, not personhood, and AI-generated speech can now convincingly impersonate humans in real time. Autonomous agents can create accounts at scale, while deepfake detectors trained to spot artifacts remain brittle and often fail against new models, codecs, or channels. In high-stakes domains such as secure communications, defense operations, and financial approvals, this uncertainty poses significant risk. Without continuous assurance of human presence, systems remain vulnerable to spoofing.

In this talk, I will present witness sensing: the use of auxiliary sensors physically and temporally coupled to media creation, providing hardware-rooted evidence of human origin. Unlike post-hoc detectors, witness sensing verifies authenticity at capture by comparing a primary modality (e.g., audio or video) with a secondary “witness” signal that reflects the same physical act but is difficult to spoof. As an example, I will focus on speech: our embedded prototype fuses radar and microphone sensing to capture articulatory motion, vocal-fold vibration, heartbeat, and respiration, synchronizing these signals with the acoustic waveform to continuously confirm both human presence and the embodied origin of speech. The result is a low-latency, tamper-resistant signal that persists throughout an interaction and remains robust to advances in generative AI.

Biography

Visar Berisha is a professor at Arizona State University with a joint appointment in the College of Engineering and the College of Health Solutions, and also serves as Associate Dean for Research Commercialization in the College of Engineering. His research sits at the intersection of speech, AI, and human communication, with a broad focus on developing technologies that improve the human condition. These range from clinical applications of speech AI in healthcare to methods that protect against the risks of generative AI and ensure the authenticity of human communication. His work, supported by the National Institutes of Health, the Department of Defense, and the National Science Foundation, has led to many academic publications and patents, as well as two startups. Berisha’s research has been featured in the New York Times, ESPN, NPR, and the Wall Street Journal. He was the International Speech Communication Association's (ISCA) 2023–24 Distinguished Lecturer.