The simplest scanners function at a lingual level. They pick up on an individual's internal dialog and perform a pattern match against a database of interest. An uncatalogued individual of interest can be added to the database upon first contact with the scanner.
A more sophisticated scanner can search for a set of people based on a common experience. This requires a more intrusive scanning algorithm to probe for the experience in a broad group of people. This kind of scanner reveals itself somewhat in the scanning process. The subject being scanned may become aware of the scanning process and be alerted to the nature of the search.
One of the benefits of a neural wave network connection is that it automatically informs the connected individual of the presence of any scanner waveform. The scanner detects the presence of the network connection and moves on to the next scan subject. The network connection serves as a sort of shield to protect network participants from intrusive scanning.