Still unsafe because I'll reveal it if they (e.g., NSA, CIA) torture me, threaten to kill my family etc.
"UC Berkeley scientists have developed a system to capture visual activity in human brains and reconstruct it as digital video clips..."
http://gizmodo.com/5843117/scientists-reconstruct-video-clip...
https://www.usenix.org/conference/usenixsecurity12/technical...