The Use of Electronic Techniques in the Construction of Machines Which Can Learn

Abstract

Four different approaches to the design and construction of electronic machines capable of displaying Pavlovian conditioning by association have been investigated theoretically and practically. Conflicts in the basic requirements for such a machine might be resolved by the introduction of Probability, Inhibition and Forgetting. The methods adopted should not make it impossible to’ introduce these features as and when required later. The methods of association information storage considered have been :- 1. Use of recordings of sinusoidal signals resulting from beats between sinusoidal input signels. This @ introduced problems of linearity in the recording process, and of selection of the input frequencies. 2. Use of rectangular waves of various frequencies. While this method could eliminate linearity problems, it introduced problems of addition of new information to previously-recorded information. 36 Use of electrical pulse signals recirculating . dynamically. While use of this method could eliminate many of the earlier problems, the problem remained of noise augmentation in a recirculating system. It is v desirable to reduce this if possible. 4. Use of pulse signals recirculating non-dynamically This fourth. method proved to be the most promising, and a machine was constructed using this approach. The organisation of this machine was based on the earlier work. Methods for further simplification are suggested in the thesis. Work on this fourth method involved the following :- 1. Consideration of methods of avoidance of Spurious response and of possible alternative methods of storage of information. 2. Development of various forms of prime-number counter. The method finally adopted used integrated circuits. 3. Investigation of a number of circuits displaying majority logic action. 4. Relationship to other work using multi-dimensional theory, and the simplification of the visualisation of associations. 5. Theoretical investigation of magnetic pulse | recording waveshapes. 6. Development of methods of construction of the machine.