This article proposes a neural network model of supervised learning that em
ploys biologically motivated constraints of using local, on-line, construct
ive learning. The model possesses two novel learning mechanisms. The first
is a network for learning topographic mixtures. The network's internal cate
gory nodes are the mixture components, which learn to encode smooth distrib
utions in the input space by taking advantage of topography in the input fe
ature maps. The second mechanism is an attentional biasing feedback circuit
. When the network makes an incorrect output prediction, this feedback circ
uit modulates the learning rates of the category nodes, by amounts based on
the sharpness of their tuning, in order to improve the network's predictio
n accuracy. The network is evaluated on several standard classification ben
chmarks and shown to perform well in comparison to other classifiers.