Think about a relationship you have with somebody in your class or workplace. Your initial relationship might be built upon what you know about that person, your shared values and common beliefs – maybe even their personal appearance. The strength of that relationship will change as soon as you start to interact with them. A friendly smile, cheerful greeting and some positive small talk will probably make you think that you might want to get to know this person a little more. Conversely, if you feel ignored, disliked or realise that you value different things, you will probably avoid them in the future. This is what we refer to in this text as student engagement – the relationship that is formed and reformed between students and education.

Learner engagement is the foundation for effective training. This chapter describes two design principles for creating engaging augmented reality-based recognition skills training. The Immersion Principle describes ways in which training designers can create a sense of learner presence in the training through cognitive and physical engagement. The Hot Seat Principle describes a strategy to increase engagement by making the learner feel a sense of responsibility for training outcomes. This is particularly useful for team and small group training. The discussions of both principles include examples, theoretical links, and implications for people designing augmented reality training.

Participation in activities that provide opportunities for mental, physical, or social engagement have been supported as cognitively protective in later life. Theories propose how mentally stimulating activities might improve or maintain specific cognitive abilities across the life course or reduce age-related cognitive changes, for example, while physical activities might promote brain health via a reduction in cardiovascular risk profiles. Given that such lifestyles and behaviors are potentially modifiable, positive associations between activity participation and maintained cognitive abilities in old age highlight leisure-time pursuits as targets for intervention. However, associations between activity participation and cognitive aging may be prone to reverse causation: those with higher engagement across the life course might have always had higher levels of cognitive ability. Life course approaches are therefore needed to correctly identify the potentially beneficial effects of activity participation. In addition, given the growth and development of cognitive abilities across the life span, there may be specific types of activity or engagement that are beneficial at different points. Understanding the associations between mental, physical, and social activity participation and cognitive aging supports the development of interventions against age-related cognitive decline, ranging from targeted cognitive training programs to broader engagement-based approaches. An ultimate goal of research exploring activity participation and cognitive aging is to provide clear and accurate information to individuals regarding the steps they might take to promote brain health in later life.