A cortex-like learning machine for temporal hierarchical pattern clustering, detection, and recognition

• Published in: Neurocomputing (Amsterdam) Vol. 78; no. 1; pp. 89 - 103
• Main Author: Lo, James Ting-Ho
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.02.2012
• Subjects: Associative memory; Clustering; Covariance learning; Dendritic tree; Hebbian learning; Learning machine; Neural network; Pattern recognition; Spiking neuron; Unsupervised learning; Spiking neuron; Associative memory; Learning machine; Dendritic tree; Hebbian learning; Neural network; Pattern recognition; Clustering; Unsupervised learning; Covariance learning
• ISSN: 0925-2312; 1872-8286
• DOI: 10.1016/j.neucom.2011.04.046

A learning machine, called a clustering interpreting probabilistic associative memory (CIPAM), is proposed. CIPAM consists of a clusterer and an interpreter. The clusterer is a recurrent hierarchical neural network of unsupervised processing units (UPUs). The interpreter is a number of supervised processing units (SPUs) that branch out from the clusterer. Each processing unit (PU), UPU or SPU, comprises “dendritic encoders” for encoding inputs to the PU, “synapses” for storing resultant codes, a “nonspiking neuron” for generating inhibitory graded signals to modulate neighboring spiking neurons, “spiking neurons” for computing the subjective probability distribution (SPD) or the membership function, in the sense of fuzzy logic, of the label of said inputs to the PU and generating spike trains with the SPD or membership function as the firing rates, and a masking matrix for maximizing generalization. While UPUs employ unsupervised covariance learning mechanisms, SPUs employ supervised ones. They both also have unsupervised accumulation learning mechanisms. The clusterer of CIPAM clusters temporal and spatial data. The interpreter interprets the resultant clusters, effecting detection and recognition of temporal and hierarchical causes.