Hmm, came across this interesting gem in 1e Book 6 Scoundrel, page 58: NAS Sweep: A Neural Activity Sensor sweeps a building or other zone for neural activity. The brainwave patterns of authorized staff and visitors are programmed into the NAS Sweep, so any thoughts detected that do not match these patterns are tagged as belonging to unwelcome intruders. NAS Sweeps can penetrate walls and other physical obstacles.
A NAS Sweep can be avoided by psionic conditioning, by a Neural Hood (see page 82) or Neural Sheathe or by staying close to powerful EM sources such as power cables that mask the thief’s brainwaves.