Reverberating Circuits
Neurons use their activation if they fire.
Consequently, they cannot remain active by themselves.
Concepts can remain active for at least several seconds.
They can do this by being represented by a host of neurons,
a reverberating circuit of neurons which activate each
other.
It's not unlike the Game of Life. The big matrix of cells is initially
empty. A few cells are activated. Cells spread their activation until
many of the cells are activated, blinking on and off.
In the game of life, the spread of activation is done by simply
breeding rules. In CAs the spread of activation is due to axonal
connections.
There is some neuropsycholgical evidence for the existence of CAs.
Unfortunately, imaging techniques don't work well for measuring activation
of large number of individual neurons in behaving brains. We can not
actually see CAs working.
Consequently, computational modelling may be the best tool we
have to understand CAs.