For neuroergonomists who wish to apply Adaptive Control of Thought-Rational (ACT-R)Adaptive Control of Thought-Rational (ACT-R) to investigate the human mind and its structure including learning, performance, and problem-solving skills, this chapter aims at providing an overview of ACT-R with an emphasis on its modules, buffers, and sub-symbolic levels. ACT-R is a high-level computational simulation of human cognitive processing and one of the cognition theories that seek to predict human performance in real-world settings. A group of previous studies on behavioral- and neural-based cognitive modelingCognitive modeling of human cognition using ACT-R will also be discussed. Finally, this chapter presents future directions of ACT-R for neuroergonomicsNeuroergonomics research.