es a connection between two named nodes:
<pre>
intrac = {...
   'LeftClr', 'LeftClrSens';
  'RightClr', 'RightClrSens';
  ...
  'BYdotDiff', 'BcloseFast'};
</pre>
Finally, we can convert this cell array to an adjacency matrix using
the following function:
<pre>
[intra, names] = mk_adj_mat(intrac, names, 1);
</pre>
This function also permutes the names so that they are in topological
order.
Given this ordering of the names, we can make the inter-slice
connectivity matrix as follows:
<pre>
interc = {...
   'L