The cognitive architecture DUAL consists of small hybrid computational entities called DUAL agents. Each agent has a symbolic processor capable of simple symbol manipulations. There is also an activation level associated with each agent.
Activation spreads according to connectionist rules.
The speed of each symbolic processor is proportional to the activation level of the corresponding DUAL agent and varies dynamically. Thus multiple candidate-solutions to a given problem can be explored in parallel. More computational resources are dedicated to the more promising candidates and the degree of 'promise' is re-evaluated dynamically. This allows for flexible and efficient behavior of the system as a whole. The exact relationship between symbolic speed and connectionist activation is based on an energetic analogy.