Connects two layers with identical blocked_representations that use
strength_patterns. Equivalent to a special matrix of matrices, in which the
diagonal matrices have diagonal structure and off-diagonal matrices are
zero. Also equivalent to a blocked_connection of diag_connections. That
is: Matching elements are connected with excitation; mismatching elements
in the same block are connected with inhibtion; connections between
elements of different blocks have zero connections.
parameter default_value excitation 1 inhibition 0