behavior in driving and flying. With the integration of perceptual-motor capabilities, ACT-R has become increasingly popular as a modeling tool in human factors and human-computer interaction. In this domain, it has been adopted to model driving behavior under different conditions,Salvucci, D. D., & Macuga, K. L. (2001). Predicting the effects of cellular-phone dialing on driver performance. In Proceedings of the Fourth International Conference on Cognitive Modeling, pp. 25–32. Mahwah, NJ: Lawrence Erlbaum Associates. menu selection and visual search on computer application,Fleetwood, M. D. & Byrne, M. D. (2002) Modeling icon search in ACT-R/PM. Cognitive Systems Research, 3, 25–33. and web navigation. Cognitive neuroscience More recently, ACT-R has been used to predict patterns of brain activation during imaging experiments. In this field, ACT-R models have been successfully used to predict prefrontal and parietal activity in memory retrieval, anterior cingulate activity for control operations, and practice-related changes in brain activity. Education ACT-R has been often adopted as the foundation for cognitive tutors.Anderson, J. R. & Gluck, K. (2001). What role do cognitive architectures play in intelligent tutoring systems? In D. Klahr & S. M. Carver (Eds.) Cognition & Instruction: Twenty-five years of progress, 227–262. Lawrence Erlbaum Associates. . These systems use an internal ACT-R model to mimic the behavior of a student and personalize his/her instructions and curriculum, trying to "guess" the difficulties that students may have and provide focused help. Such "Cognitive Tutors" are being used as a platform for research on learning and cognitive modeling as part of the Pittsburgh Science of Learning Center. Some of the most successful applications, like the Cognitive Tutor for Mathematics, are used in thousands of schools across the United States. Brief history Early years: 1973–1990 ACT-R is the ultimate successor of a series of increasingly precise models of human cognition developed by John R. Anderson. Its roots can be backtraced to the original HAM (Human Associative Memory) model of memory, described by John R. Anderson and Gordon Bower in 1973. The HAM model was later expanded into the first version of the ACT theory. This was the first time the procedural memory was added to the original declarative memory system, introducing a computational dichotomy that was later proved to hold in human brain. The theory was then further extended into the ACT* model of human cognition. Integration with rational analysis: 1990–1998 In the late eighties, Anderson devoted himself to exploring and outlining a mathematical