  Deepfakes are computationally-created entities that falsely represent
reality. They can take image, video, and audio modalities, and pose a threat to
many areas of systems and societies, comprising a topic of interest to various
aspects of cybersecurity and cybersafety. In 2020 a workshop consulting AI
experts from academia, policing, government, the private sector, and state
security agencies ranked deepfakes as the most serious AI threat. These experts
noted that since fake material can propagate through many uncontrolled routes,
changes in citizen behaviour may be the only effective defence. This study aims
to assess human ability to identify image deepfakes of human faces
(StyleGAN2:FFHQ) from nondeepfake images (FFHQ), and to assess the
effectiveness of simple interventions intended to improve detection accuracy.
Using an online survey, 280 participants were randomly allocated to one of four
groups: a control group, and 3 assistance interventions. Each participant was
shown a sequence of 20 images randomly selected from a pool of 50 deepfake and
50 real images of human faces. Participants were asked if each image was
AI-generated or not, to report their confidence, and to describe the reasoning
behind each response. Overall detection accuracy was only just above chance and
none of the interventions significantly improved this. Participants' confidence
in their answers was high and unrelated to accuracy. Assessing the results on a
per-image basis reveals participants consistently found certain images harder
to label correctly, but reported similarly high confidence regardless of the
image. Thus, although participant accuracy was 62% overall, this accuracy
across images ranged quite evenly between 85% and 30%, with an accuracy of
below 50% for one in every five images. We interpret the findings as suggesting
that there is a need for an urgent call to action to address this threat.
