Abstract: In a neural network of N neuron circuits, having an engaged neuron's calculated p bit wide distance between an input vector and a prototype vector and stored in the weight memory thereof, an aggregate search/sort circuit (517) of N engaged neurons' search/sort circuits. The aggregate search/sort circuit determines the minimum distance among the calculated distances. Each search/sort circuit (502-1) has p elementary search/sort units connected in series to form a column, such that the aggregate circuit is a matrix of elementary search/sort units. The distance bit signals of the same bit rank are applied to search/sort units in each row. A feedback signal is generated by ORing in an OR gate (12.1) all local search/sort output signals from the elementary search/sort units of the same row. The search process is based on identifying zeroes in the distance bit signals, from the MSB's to the LSB's. As a zero is found in a row, all the columns with a one in that row are excluded from the subsequent row search.

Abstract: In a neural network comprised of a plurality of neuron circuits, an improved neuron circuit that generates local result signals, e.g. of the fire type, and a local output signal of the distance or category type. The neuron circuit which is connected to buses that transport input data (e.g. the input category) and control signals. A multi-norm distance evaluation circuit calculates the distance D between the input vector and a prototype vector stored in a R/W memory circuit. A distance compare circuit compares this distance D with either the stored prototype vector's actual influence field or the lower limit thereof to generate first and second comparison signals. An identification circuit processes the comparison signals, the input category signal, the local category signal and a feedback signal to generate local result signals that represent the neuron circuit's response to the input vector.