  Connectionist systems offer a means of computation that, in many cases, eschews the symbolist commitments of computational cognitive science. In contrast to the computer that operates on symbols on the basis of internally stored rules, a connectionist system consists in networks of nodes that excite or inhibit each other’s activity according to weighted connections between them. Different stimuli will affect input nodes differently, causing distinct patterns of activation in deeper layers of nodes depending on the values of activation that the input nodes send upstream. The result of this activity will reveal itself in the activation values of a final layer of nodes—the output nodes.