Editing Perceptron (section)

=== ''Principles of Neurodynamics'' (1962) ===
Rosenblatt described his experiments with many variants of the Perceptron machine in a book ''Principles of Neurodynamics'' (1962). The book is a published version of the 1961 report.<ref>''[[iarchive:DTIC AD0256582/|Principles of neurodynamics: Perceptrons and the theory of brain mechanisms]]'', by Frank Rosenblatt, Report Number VG-1196-G-8, Cornell Aeronautical Laboratory, published on 15 March 1961. The work reported in this volume has been carried out under Contract Nonr-2381 (00) (Project PARA) at C.A.L. and Contract Nonr-401(40), at Cornell Univensity.</ref>

Among the variants are:

* "cross-coupling" (connections between units within the same layer) with possibly closed loops, 
* "back-coupling" (connections from units in a later layer to units in a previous layer), 
* four-layer perceptrons where the last two layers have adjustible weights (and thus a proper multilayer perceptron),
* incorporating time-delays to perceptron units, to allow for processing sequential data,
* analyzing audio (instead of images).
The machine was shipped from Cornell to Smithsonian in 1967, under a government transfer administered by the Office of Naval Research.<ref name=":1" />