  The wide spread of fake news in social networks is posing threats to social
stability, economic development and political democracy etc. Numerous studies
have explored the effective detection approaches of online fake news, while few
works study the intrinsic propagation and cognition mechanisms of fake news.
Since the development of cognitive science paves a promising way for the
prevention of fake news, we present a new research area called Cognition
Security (CogSec), which studies the potential impacts of fake news to human
cognition, ranging from misperception, untrusted knowledge acquisition,
targeted opinion/attitude formation, to biased decision making, and
investigates the effective ways for fake news debunking. CogSec is a
multidisciplinary research field that leverages knowledge from social science,
psychology, cognition science, neuroscience, AI and computer science. We first
propose related definitions to characterize CogSec and review the literature
history. We further investigate the key research challenges and techniques of
CogSec, including human-content cognition mechanism, social influence and
opinion diffusion, fake news detection and malicious bot detection. Finally, we
summarize the open issues and future research directions, such as early
detection of fake news, explainable fake news debunking, social contagion and
diffusion models of fake news, and so on.
