Most elderly people staying in nursing homes have dementia, and various kinds of recreational programs are provided in order to prevent or ameliorate this problem. Robot therapy is a recreational program that has recently been introduced in some nursing homes. However, the effects of robot therapy are difficult to evaluate. In this study, we identified events occurring during therapy that are important in the proliferation and evolution of robot therapy. We also found that the presence of an intervener encourages elderly people to be more active.

Most elderly people staying in nursing homes have considerable dementia, and various kinds of recreation program have hence been executed in order to improve or prevent this problem. However the effect of recreation has not been proved quantitatively. In this paper, we show the relationship between actions of elderly people with considerable dementia during recreation and abilities of memorization, emotion control, accommodation to society, etc., and decompose their actions into basic action factors. We propose a design method for recreation programs composed of effective factor actions for improving dementia. We analyze the effect of recreation in an experiment of robot therapy recreation based on the proposed method.