This memory contains the current goal and all of the information generated during the execution cycle.
This memory is the agents model of the world. This is maintained by perceptions and by the current state of the agent's problem solving task.
This memory is used as a visio-spatial scratchpad that allows the agent to "imagine" or plan tasks without effecting the actual environment. To model the human characteristic that the imagination is volatile, the agent is allowed only a architecturally specified number of operations to the scratchpad before it becomes unavailable.
This is the immediate recall area that is used to emulate the behavior in untrained subjects to quickly store and recall 7 chunks of information. This Information in this memory lasts for 2-3 seconds.