  Advances in techniques for the formal analysis of neural networks have
introduced the possibility of detailed quantitative analyses of brain
circuitry. This paper applies a method for calculating mutual information to
the analysis of the Schaffer collateral connections between regions CA3 and CA1
of the hippocampus. Attention is given to the introduction of further details
of anatomy and physiology to the calculation: in particular, the distribution
of the number of connections that CA1 neurons receive from CA3, and the graded
nature of the firing-rate distribution in region CA3.
