Feature units have excitatory connections to all of the letter units in the same spatial position that have those features and inhibitory weights to those that do not have those features.
Letter-to-word weights
Each letter unit in a given position has excitatory connections to the word units that have that letter in that position, and inhibitory connections to all of the word units that do not have that letter in that position.
The feature-to-letter and letter-to-word weights embody the bottom-up knowledge of the network.
