This study aimed to elucidate the effect of introducing an information support robot on utterance frequency and confirm the change in utterance frequency after long-term use. We presented an information support robot installed with individualized content to three older adults with cognitive impairment who live alone at home or in an assisted living residence (mean age 83.7±SD 5.4 years). Changes in the participants' utterance frequency over six months following the intervention of long-term robot use in actual living spaces were quantitatively recorded and analyzed. Two participants' total utterance frequency maintained or improved. With robot intervention, the utterance frequency to the robot was maintained for six months. When the usability and satisfaction with the robot were high, the utterance frequency increased. These results suggest that users need to be provided with personalized information that is appropriate for their individual needs to use robots effectively over the long term. Information support robots have the potential for long-term use without inflicting boredom and may encourage more frequent interactions. Long-term use of such information support robots may help older adults to continue living autonomously and independently for longer. These findings may contribute to future efforts in supporting autonomous living.

Keywords: cognitive function; dementia; living alone; older adults; robot.

这项研究旨在阐明引入信息支持机器人对说话频率的影响，并确认长期使用后说话频率的变化。我们向三名独自居住在家或辅助生活设施中的认知障碍老年人（平均年龄83.7±SD 5.4岁）提供了一个安装了个性化内容的信息支持机器人。我们在六个月的干预期内，定量记录并分析了参与者在实际生活环境中的说话频率变化。

两名参与者的总说话频率保持不变或有所提高。通过机器人的介入，在六个月内与机器人的对话频率得以维持。当机器人易用性和满意度较高时，说话频率会增加。这些结果表明，为了长期有效地使用机器人，用户需要获得符合其个人需求的个性化信息。信息支持机器人有可能在不引起厌烦的情况下进行长期使用，并且可能鼓励更频繁的互动。此类信息支持机器人的长期使用可能会帮助老年人更长时间地独立自主生活。

关键词：认知功能；痴呆症；独自居住；老年人；机器人。