When two more characteristics of voice to skull are factored in:

1. The carrier signal can be "hopped" continuously within the 
   bioeffective bandwidth, known as "spread spectrum" transmission, 
   and,

2. The voice modulation most effective for undetectable hypnosis 
   is evidently a voice shifted just above normal hearing, but still 
   audible to the brain,

...you have a recipe for incredibly difficult signals to detect.

This book is a mainstream publication, very well suited to use 
in our publicity and persuasion campaigns, and our dealings with 
authorities who claim radio signals don't affect living tissue 
except to heat it.

Finally, many thanks to Blanche Chavoustie for providing me
photocopies of this book - a saintly work!
.............................................................
Page 110:
...
At that time [1953] excitatory mechanisms in nerver fibers
and nerve cells were grouped under a common rubric of ionic
equilibrium mechanisms.  There was little interest in the
possibility that functional organization of mebranes of cell
bodies might involve threshhold sensitivities to both
oscillating EM fields and to molecular stimuli at energy
levels substantially lower than predicted by Hodgkin-
Huxley models, and substantially below typical threshholds
in nerve fibers.

Much recent research cited below has shown that imposed weak
low frequency fields (and radiofrequency fields amplitude-
modulated at ELF frequencies) that are many orders of 
magnitude weaker in the pericellular fluid [fluid between
adjacent cells] than the membrane potential gradient [voltage
across the membrane] can modulate actions of hormone, anti-
body neurotransmitter and cancer-promoter molecules at their
cell surface receptor sites.

From their electrical characteristics, these sensitivities
appear to involve nonequilibrium and highly cooperative
processes that mediate a major amplification of initial
weak triggers associated with binding of these molecules at
their specific cell surface receptor sites.

                                -49-