The phenomenal evolution of artificial intelligence (AI) and information technology now surpass the evolution of the human brain, creating a "capability gap" between humans and technology. Research related to this theme aims to bridge this gap and harmonize the relationship between human intelligence and AI in order to maximize performance and improve quality of life. A promising avenue lies in the development of adaptive systems. These so-called "intelligent" systems can adapt their actions (whether it be the interface, the information they distribute, the tasks they perform and delegate, or the feedback they provide) dynamically based on the functional behavior and state of the system user (e.g., the cognitive state of an airplane pilot to modulate autopilot or the success of the learner's cognitive load to customize the content of an educational game). The adaptive capacity of an intelligent system relies on the continuous, almost real-time, evaluation of the cognitive and affective state of the human agent. Advances in the technological aspects of adaptive systems are proceeding at a rate dangerously faster than the cognitive and neuroscience research on which such advances should be based.