By way of explaining how a brain works logically, human associative memory is modeled in this chapter with logical neurons, and these of course correspond to standard digital circuits. The resulting architecture is based on standard digital circuits to incorporate psychological elements including short- and long-term memory. Novel to the architecture are memory searches using cues chosen pseudorandomly from short-term memory. Recalls, alternated with sensory images, many tens per second, are assumed to be analyzed subliminally as an ongoing process, to determine a direction of attention in short-term memory. What is modeled below is not just human memory, but a human memory system that includes the possibility of solving problems and learning: in other words, the beginnings of a cognitive architecture to explain human intelligence.
In this chapter we show how to synthesize circuits for human associative memory, including circuits for memorization and recall, using standard digital building blocks. Inputs to memory circuits are the axons of neurons that encode sensory information, each communicating an encoded feature, shape, shade, tone, and so on, of sensory data true or false. These axons connect in parallel to respective cells in conscious short-term memory assuming a specific but unknown physical location for each feature.
Short-term-memory cells are modeled as connecting to corresponding cells of subconscious ...