Deep fake technology poses a significant threat to the political discourse. Within the realm of information systems (IS) research, the study of fake news on social media has primarily focused on written text, with comparatively little emphasis on deep fake videos. However, the effectiveness of visual content in persuading users of the authenticity of the events presented surpasses that of textual content, a phenomenon underscored by IS research. In this study, we analyze whether the theories of confirmation bias and cognitive dissonance are also applicable to deep fake videos. To this end, we propose a between-subject experiment with measurements of brain activity and heart rate to shed light on the underlying cognitive and affective processes that guide users’ behavior and beliefs. Accordingly, we contribute to the IS literature by employing neurophysiological measurements to analyze human processing of deep fakes, which assists social media platforms in developing effective mitigation strategies.