Thanks Paul. False fonts have the same visual complexity as real letters, but are meaning less. Similar visual complexity means false fonts have the same number of strokes and inflection points as real letters. An example can be seen in this paper
http://white.stanford.edu/~brian/pap...ortex-2006.pdf
In our research we are measuring brain response to letters in 3-4 year old children. We need a control stimulus (false fonts) for the comparison purpose.