"What I See is What I Hear": Deepfake Detection Across Diverse Hearing Abilities
The proliferation of audiovisual deepfakes has lowered the cost of fraud, impersonation, and misinformation, but their success ultimately depends on human perception. Detection requires integrating auditory and visual cues, yet security and privacy research has largely overlooked d/Deaf and hard-of-hearing (DHH) populations. We address this gap with an in-person, mixed-methods study of 80 participants: 31 hearing persons (HPs), 15 hard-of-hearing (HoH) participants, 17 d/Deaf participants, and 17 cochlear implant (CI) users. Each participant judged the authenticity of 30 clips, where manipulations spanned text-to-speech, voice conversion, lip-sync, or face-swap. DHH participants were less accurate than HPs overall (76.4% vs. 88.0%, p<.001), primarily because they more often classified authentic clips as manipulated (FPR: 29.7% vs. 11.2%). Differences depended strongly on the manipulated channel. For audio-only manipulations, HoH participants matched HPs (90.0% vs. 90.3%), followed by CI users (79.4%) and d/Deaf participants (41.2%). When clips contained an audiovisual manipulation, accuracy clustered between 84% and 87%, although performance still varied by manipulation method. Our work systematically characterizes how deepfakes affect DHH populations, highlighting the asymmetric risks audiovisual manipulations may pose to groups with different hearing abilities and the need for accessible, tailored defenses that support all users.