Computing conditional probabilities in a minimal CA3 pyramidal neuron

The function of the CA3 region of the hippocampus can be explained in terms of a sequence predicting recoder. For the CA3 to act as a neural prediction device, each CA3 neuron must also act as a predictor. Thus, such neurons, as prediction devices, compute something that might approximate a conditional probability. In particular, we conjecture that each neuron forecasts its own firing. Here we compare a simple neural network model, based on synaptic encoding of local conditional probabilities to an even simpler model of hippocampal region CA3 that succeeds on a variety of hippocampally dependent learning tasks. r 2004 Elsevier B.V. All rights reserved.