An Integrated Theory of the Mind John Anderson et al. Psychological Review, 111, 1036-1060 (2004)
ACT Computational cognitive model 20-30 years, army of researchers Model & modeling environment Applied to many cognitive tasks Constrained by common architecture & parameters Initially focused on high-level cognition Elaborated with perceptual-motor modules
Architecture Long-term Memory Goals Productions Working Memory Perception Action
Productions If-Then rules Triggered by contents of WM Depend on current goal, knowledge, and perceptual input Outputs: Update goal Update declarative knowledge Perform action “Central decision makers”
Example Declarative Knowledge Goal Stack Do Addition Addition Fact Add Units Summand 3 Working Memory Recall Sum Summand 4 Sum 7 Goal: Add Units Summand 3 Sum 7 Summand 4 IF: Goal = Recall Sum Summand X Summand Y Addition Fact: X + Y = Z THEN: Remove Summand X Remove Summand Y Add Sum Z Pop Goal IF: Goal = Add Units Sum X THEN: Write X Pop Goal Goal: Recall Sum Motor Perception 73 +44 “7”
Issues Characterization of modules Subsymbolic processing Learning Modeling complex tasks Mapping to neuroanatomy